caenrfid Lepton7 R7100C Technical document

TECHNICAL INFORMATION MANUAL
Revision 0.2 - 30/06/2022
R7100C
Lepton7
30dBm 1-Port RAIN RFID Reader Module

Visit the Lepton7R7100C web page, you will find the latest revision
of data sheets, manuals, certifications, technical drawings, software and firmware.
All you need to start using your reader in a few clicks!
Scope of Manual
The goal of this manual is to provide the basic information to work with the Lepton7R7100C Reader.
Change Document Record
Date
Revision
Changes
Pages
07/04/2022
0
Preliminary revision
-
19/05/2022
0.1
Added Federal Communications Commission (FCC) Notice
(Preliminary)
3
Added FCC Compliance paragraph in the Regulatory Compliance
chapter
21,22
30/06/2022
0.2
Corrected minimum separation distance requirement
21,22
Reference Document
[RD1] EPCglobal: EPC Radio-Frequency Identity Protocols Class-1 Generation-2 UHF RFID Protocol for
Communications at 860 MHz –960 MHz, Version 2.0.1 (April 2015).
CAEN RFID srl
Via Vetraia, 11 55049 Viareggio (LU) - ITALY
Tel. [phone] Fax [phone]
[email protected]
www.caenrfid.com
© CAEN RFID srl –2022
Disclaimer
No part of this manual may be reproduced in any form or by any means, electronic, mechanical, recording, or
otherwise, without the prior written permission of CAEN RFID.
The information contained herein has been carefully checked and is believed to be accurate; however, no
responsibility is assumed for inaccuracies. CAEN RFID reserves the right to modify its products specifications
without giving any notice; for up to date information please visit www.caenrfid.com.
Preliminary Product Information
This document contains information for a new product. CAEN RFID reserves the right to modify this product
without notice.
“Preliminary” product information describes products that are ready for production, but for which full
characterization data is not yet available. CAEN RFID believes that the information contained in this document is
accurate and reliable. However, the information is subject to change without notice and is provided “AS IS”
without warranty of any kind (Express or implied). You are advised to obtain the latest version of relevant
information to verify, before placing orders, that information being relied on is current and complete. All products
are sold subject to the terms and conditions of sale supplied at the time of order acknowledgement, including
those pertaining to warranty, patent infringement, and limitation of liability. No responsibility is assumed by CAEN
RFID for the use of this information, including use of this information as the basis for manufacture or sale of any
items, or for infringement of patents or other rights of third parties.

Federal Communications Commission (FCC) Notice (Preliminary)
This device was tested and found to comply with the limits set forth in Part 15 of the FCC Rules. Operation is
subject to the following conditions: (1) this device may not cause harmful interference, and (2) this device must
accept any interference received including interference that may cause undesired operation. These limits are
designed to provide reasonable protection against harmful interference when the equipment is operated in a
commercial environment.
This device generates, uses, and can radiate radio frequency energy. If not installed and used in accordance with
the instruction manual, the product may cause harmful interference to radio communications. Operation of this
product in a residential area is likely to cause harmful interference, in which case, the user is required to correct
the interference at their own expense. The authority to operate this product is conditioned by the requirements
that no modifications be made to the equipment unless the changes or modifications are expressly approved by
CAEN RFID.
Disposal of the product
Do not dispose the product in municipal or household waste. Please check your local
regulations for disposal/recycle of electronic products.

INDEX - Lepton7- Technical Information Manual 4
Index
Scope of Manual ........................................................................................................................................................................2
Change Document Record .......................................................................................................................................................2
Reference Document.................................................................................................................................................................2
1Introduction......................................................................................................................................................................6
Description..................................................................................................................................................................................6
Reader ............................................................................................................................................................................6
2Technical Specifications ................................................................................................................................................7
Technical Specifications ...........................................................................................................................................................7
Key Features...............................................................................................................................................................................8
3Hardware Interface .........................................................................................................................................................9
Introduction.................................................................................................................................................................................9
Power Supply ...........................................................................................................................................................................10
RF Connection..........................................................................................................................................................................10
UART Communication.............................................................................................................................................................10
Reset Pin ...................................................................................................................................................................................11
GPIO Pins..................................................................................................................................................................................11
Wakeup Pin...............................................................................................................................................................................12
Pin Listing and Signal Definitions...........................................................................................................................................12
Electrical Specifications ..........................................................................................................................................................13
Absolute Maximum Ratings........................................................................................................................................13
Operating Conditions..................................................................................................................................................14
Device Functional Specifications ..............................................................................................................................14
UHF Gen 2 RFID Radio Specifications .....................................................................................................................15
Device Input and Output Specifications ...................................................................................................................15
4Layout and Components ..............................................................................................................................................17
Introduction...............................................................................................................................................................................17
PCB Layout for RF ...................................................................................................................................................................17
50 Ohm Characteristic Impedance ...........................................................................................................................17
Package and Assembly Information ......................................................................................................................................18
Package Mass..............................................................................................................................................................18
Package Dimensions...................................................................................................................................................18
PCB Footprint ..............................................................................................................................................................19
SMT Reflow Information .............................................................................................................................................19
Moisture Sensitive Level 3 (MSL 3) ..........................................................................................................................20
5Regulatory Compliance ................................................................................................................................................21
RoHS EU Directive...................................................................................................................................................................21
FCC Compliance......................................................................................................................................................................21

INDEX - Lepton7- Technical Information Manual 5
List of Figures
Fig. 1.1: Lepton7Reader –top view....................................................................................................................................................6
Fig. 1.2: Lepton7 Reader –back view ................................................................................................................................................6
Fig. 3.1: Lepton7R7100C - Example of Block Diagram....................................................................................................................9
Fig. 3.2: BSL sequence ......................................................................................................................................................................10
Fig. 3.3: Lepton7R7100C Pin Listing................................................................................................................................................12
Fig. 4.1: PCB Transmission Line Types............................................................................................................................................17
Fig. 4.2: Package Dimensions, Top, Front, and Side Views ..........................................................................................................18
Fig. 4.3: Recommended Etched Copper Footprint –All Pads.......................................................................................................19
Fig. 4.4: Recommended Solder Reflow Profile for the Lepton7R7100C .....................................................................................19
List of Tables
Tab. 2.1: Lepton7R7100C Technical Specifications ........................................................................................................................7
Tab. 3.1: Pin Listing and Signal Definitions......................................................................................................................................13
Tab. 3.2: Absolute Maximum Ratings ...............................................................................................................................................13
Tab. 3.3: Operating Conditions .........................................................................................................................................................14
Tab. 3.4: Supply Current Specifications ..........................................................................................................................................14
Tab. 3.5: Startup and Wakeup Time.................................................................................................................................................14
Tab. 3.6: RF Receiver Specifications................................................................................................................................................15
Tab. 3.7: RF Transmitter Specifications ...........................................................................................................................................15
Tab. 3.8: Digital Interface Specification............................................................................................................................................15
Tab. 3.9: Analog Interface Specification ..........................................................................................................................................16

INTRODUCTION - Lepton7- Technical Information Manual 6
1INTRODUCTION
Description
Reader
The Lepton7(Model R7100C), an embedded reader of the easy2read©product line, is an ultra compact reader
for low power, high performance RAIN RFID applications.
With programmable output power from 10dBm to 30dBm, the reader can detect tags at more than 5 mt of
distance (depending on antenna and tag dimensions).
Due to its low power consumption, the module is specifically designed to be easily integrated in battery
powered devices.
The radio frequency core of the module is based on the Impinj E710 IC that permits to achieve fast reading
speed and to be used in dense reader and dense tag environments for top-class rated performances.
The compactness of the device and the surface mount technology allow to embed the Lepton7inside the new
small form factor industrial handhelds, smartphone accessories and other compact form factor devices.
The Lepton7complies with and can operate in both European and US regulatory environments and, thanks to
its multiregional capabilities, it’s ideal for integration in devices requiring compliance to different geographical
regions.
The Lepton7is pin-to-pin compatible with the Impinj RS1000 and RS500 modules making it a perfect
replacement for these devices.
Fig. 1.1: Lepton7Reader –top view
Fig. 1.2: Lepton7 Reader –back view

TECHNICAL SPECIFICATIONS - Lepton7- Technical Information Manual 7
2TECHNICAL SPECIFICATIONS
Technical Specifications
Frequency Range
865.600÷867.600 MHz (ETSI EN 302 208 v3.3.1)
902÷928 MHz (FCC part 15.247)
RF Power
Configurable from 10 dBm to 30 dBm (from 10 mW to 1W) conducted
power
RX Sensitivity
-85dBm –10%PER, assuming 20 dB antenna RL @ 30 dBm output
Antenna VSWR
Requirement
< 2:1 for optimum performances
Antenna Connectors
50 Ohm mono-static RF port on a single pin
Frequency Tolerance
±10ppm over the entire temperature range
Number of Channels
4 channels (compliant to ETSI EN 302 208 v3.3.1)
50 hopping channels (compliant to FCC part 15.247)
Standard Compliance
EPC C1G2 / ISO18000-63
I/O Interface
4 I/O lines 3.3V level
Iout @ 8mA max
Connectivity
UART Serial Port
Baudrate: from 9.6 to 921.6 kbps, default 921.6 kbps
Databits: 8
Stopbits:1
Parity: none
Flow control: none
3.3 V I/O voltage level
Power Supply
4.75 ÷ 5.25 V DC
Power Consumption
-1.4 A @ 5 V - RF out = 30 dBm
-5 mA in idle mode - Ready to receive commands
Dimensions
(L) 32 x (W) 29 x (H) 4.1 mm3
1.26 x 1.14 x 0.16 inches3
Package Type
32 pin surface mount module (SMT compatible)
Operating Temperature
-20°C to +70°C
Weight
5.4 g
Tab. 2.1: Lepton7R7100C Technical Specifications
Y
Warning: The RF settings must match the operating country/region to comply with local laws and
regulations.
The usage of the reader in different countries/regions from the one in which the device has been
sold is not allowed.

TECHNICAL SPECIFICATIONS - Lepton7- Technical Information Manual 8
Key Features
RAIN RFID (UHF EPC Class1 Gen2, ISO 18000-63) compliant
Both ETSI and FCC support in the same module
Ultra compact size
Up to 30 dBm (1W) output power
-85 dBm Rx sensitivity, assuming 20 dB antenna return loss
Impinj RS500 and RS1000 pin-to-pin compatibility
Inventory (FastID, Tag Population Estimate, Select, Session, Target)
Access (Read, Write, Lock, Kill, BlockPermalock, and QT)
Shielded to prevent unwanted radiation and provide noise immunity in embedded environments
29 mm by 32 mm by 4.1 mm surface mount package with SMT compatibility
Single mono-static RF port
Field upgradability via firmware updates. Gen 2 v2 will be firmware upgradable
UART serial interface using CAEN RFID easy2read©protocol
Test features (CW, PRBS, custom regions, channel lists, and fixed frequency)

HARDWARE INTERFACE - Lepton7- Technical Information Manual 9
3HARDWARE INTERFACE
Introduction
An example Lepton7R7100C system-level block diagram for an embedded system is shown in Fig. 3.1:
Lepton7 R7100C - Example of Block Diagram. This figure shows the electrical connections that may and must
be made to control the Lepton7R7100C. In the figure, the required connections are illustrated with solid lines.
Recommended and optional connections are illustrated with different dotted and dashed line patterns. More
details for each connection are listed in the following paragraphs.
Fig. 3.1: Lepton7R7100C - Example of Block Diagram
Required connections:
•VDC_IN and GND are required to power the Lepton7R7100C.
•RF is required to connect to the UHF RFID antenna.
•UART1 Tx and Rx are required to communicate with the system host.
Recommended connections:
•nRST is used to reset the Lepton7R7100C if UART communication is not available. This connection is
highly recommended. This pin is internally driven strong low during software resets, so it should only be
driven externally by an open drain signal. It must not be driven strong high.
•TST and BSL_SEL shall be used for the FW recovery/upgrade procedure.
In order to start the Boot Strap Loader of Lepton7 internal microcontroller NRST, TST and BSL_SEL
signals shall be driven as in the picture below:

HARDWARE INTERFACE - Lepton7- Technical Information Manual 10
Fig. 3.2: BSL sequence
The BSL program execution starts when TST pin has received a minimum of two positive transitions and
if TST is high while /RST rises from low to high. BSL_SEL shall be at high level before BSL starts. Pulses
length and distance between edges of all signals shall be 10ms at least.
•UART2 Tx and Rx may be used to examine debug information.
Optional connections:
•GPIOs allow interaction with the Lepton7R7100C as both digital inputs and outputs. They may be used to
trigger inventory, generate events based on inventory activity, or provide general-purpose user-
controlled digital I/O.
•WKUP provides a mechanism to wake up the Lepton7R7100C from the low power Sleep mode. If
unused, this pin should be tied to logic low.
•UC_ADC allows use of an ADC to convert an analog input voltage into a digital value.
•UC_DAC allows use of a DAC to generate an analog output voltage from a digital value.
•RFU is a GPIO reserved for future use.
Power Supply
The Lepton7R7100C is powered by a voltage applied to the VDC_IN pin (pin 11) relative to the GND pins. The
supply voltage operating range is 4.75 V to 5.25 V. Current consumption varies from about 1400 mA to about
5mA depending on the operating mode. The power supply is internally bypassed and regulated, and no
external bypass or bulk storage capacitance is required, as long as the input voltage is stable.
If Lepton7R7100C activity is not required at all times, and power reduction is desired, the VDC_IN supply
voltage may be externally gated to remove power to the device.
RF Connection
The Lepton7R7100C has a single RF pin (pin 1) which should be connected to a 50 Ω antenna via 50 Ω
controlled impedance connection. This connection could simply be a microstrip transmission line to a PCB
antenna or SMT antenna, or it could include a connector and coaxial cable. The RF connection is single
ended, referenced to ground.
For more information about impedance matching, see PCB Layout for RF page 17.
UART Communication
The Lepton7R7100C has two full-duplex UART standard interfaces, accessible using pins UART1-RX, UART1-
TX, UART2-RX, and UART2-TX. UART1 implements the host communication interface via easy2read©, and
UART2 implements the debug interface (RFU). The Tx pins are outputs from the Lepton7R7100C, and the Rx
pins are inputs to the Lepton7R7100C. Both UART interfaces are 921,600 baud, with 8 data bits, 1 stop bit,
and no parity bit (8-n-1 configuration).

HARDWARE INTERFACE - Lepton7- Technical Information Manual 11
Each of the UART interfaces signals at 3.3 V relative to GND. The specific VIH, VIL, VOH and VOL
specifications may be found in the § Device Input and Output Specifications paragraph page 15. The TX pins
are driven strong high and low with a sink/source current of about 8 mA. If the load on a pin draws more than
the 8 mA sink and source current, the pin is not guaranteed to meet the VOH and VOL specs listed in §
Device Input and Output Specifications paragraph page 15. Excessive current sunk or sourced on the GPIO
pins can also cause electrical damage to the device.
Y
Warning: Voltages outside of the maximum IO operating voltage range of -0.3 to 4.0 V should not
be applied to the UART pins. This can cause permanent damage to the device.
Reset Pin
The Lepton7R7100C may be reset by a logic low voltage on the NRST pin (pin 9). Usage of this pin is
recommended in all designs. It may be used to reset the part if an unexpected operating state is entered. The
Lepton7R7100C does have an internal watchdog circuit that will reset it if abnormal operation occurs, but the
NRST pin provides a further level of reliability.
The NRST pin is pulled high (3.3 V) by an internal 51,1 kΩ nominal resistor. To reset the part, drive the pin
strong low for at least the minimum reset pulse width as specified in § Device Input and Output Specifications
paragraph page 15 (approximately 25 μs). This pin may be driven active low to reset the part, but should not
be driven strong high. Driving the pin strong high prevents the Lepton7R7100C from resetting itself in case
user requested software reset. This pin should be driven using an “open drain drives low” drive mode, which
creates either a strong low voltage or a floating voltage output.
Y
Warning: Voltages outside of the maximum IO operating voltage range of -0.3 to 4.0 V should not
be applied to the NRST pin. This can cause permanent damage to the device.
GPIO Pins
The Lepton7R7100C’s GPIOs can be controlled using the easy2read©interface. Their drive mode, direction,
and state are all controllable via easy2read©. There are two directions: input and output. In both input and
output directions, there are three possible pin states: high, low, and float. For more details on using
easy2read©to control the GPIOs, see the easy2read©protocol documentation.
In the output direction, the GPIOs are driven strong high and low with a source and sink current of 8 mA, and
in float mode the pin is not driven either high or low, leaving the pin floating, also known as “high impedance”
or “high-Z”. The pins are driven to 3.3 V nominally. If the load on a pin draws more than the 8 mA sink and
source current, the pin is not guaranteed to meet the VOH and VOL specs listed in the § Device Input and
Output Specifications paragraph page 15.
Y
Warning: Excessive current sunk or sourced on the GPIO pins can also cause electrical damage
to the device.
In the input direction, the high and low states apply a pull-up or pull-down resistor, and in float mode the pin is
not pulled either high or low, leaving the pin floating, also known as “high impedance” or “high-Z”. The pull-up
and pull-down resistors are about 35 kΩ nominal. See the § Device Input and Output Specifications
paragraph page 15 for more specific ratings. The inputs logic levels are proportional to 3.3 V. Specific VIH
and VIL specs may be found in the § Device Input and Output Specifications paragraph page 15.
Y
Warning: Voltages outside of the maximum IO operating voltage range of -0.3 to 4.0 V should not
be applied to the pins, no matter their configuration. This can cause permanent damage to the
device.

HARDWARE INTERFACE - Lepton7- Technical Information Manual 12
Wakeup Pin
The WKUP pin is used to wake the device when it is in the Standby or Sleep operating modes. This pin is
edge sensitive and will wake the device on a rising edge. The WKUP pin must be logic low in order for the
device to re-enter Idle mode after a Sleep wakeup, so it should only be pulsed high to wake up the part.
The WKUP pin operates at a 3.3 V logic level. It has a 35 kΩ typical pull-down resistor inside the Lepton7
R7100C. Voltages outside of the maximum IO operating voltage range of -0.3 to 4.0 V should not be applied to
the WKUP pin. This can cause permanent damage to the device.
If the WKUP pin is not used, it should be left floating or tied to logic low (ground).
Pin Listing and Signal Definitions
Fig. 3.3: Lepton7R7100C Pin Listing

HARDWARE INTERFACE - Lepton7- Technical Information Manual 13
Pin#
Pin Name
Pin Type
Description
1
RF
RF
RF antenna port
2
GND
Power
Ground
3
RFU
Digital I/O
Reserved for Future Use
4
BSL_SEL
Digital Input
Boot Strap Loader interface enable signal
5
GND
Power
Ground
6
TST
Digital Input
TST pin to be used for FW recovery/upgrade
7
UART1-RX
Digital Input
R7100C UART Rx (Receive) from host
8
UART1-TX
Digital Output
R7100C UART Tx (Transmit) to host
9
NRST
Digital Input
Active low reset. Connect to open drain driver. R7100C must be
able to internally pull down this signal to reset.
10
GND
Power
Ground
11
VDC_IN
Power
DC voltage supply (4.75 –5.25 V)
12
WKUP
Digital Input
Wakeup from sleep on rising edge
13
UC_ADC
Analog Input
Analog to digital converter input
14
UART2-TX
Digital Output
R7100C Debug UART Tx to host
15
UART2-RX
Digital Input
R7100C Debug UART Rx from host
16
UC_DAC
Analog output
Digital to analog converter output
17
GPIO1
Digital I/O
General purpose I/O
18
GPIO2
Digital I/O
General purpose I/O
19
GPIO3
Digital I/O
General purpose I/O
20
GPIO4
Digital I/O
General purpose I/O
21
STATUS
Digital Output
R7100C status indication
22
HEALTH
Digital Output
R7100C health indication
23-32
GND
Power
Ground pins on the top and bottom edge of the package
Tab. 3.1: Pin Listing and Signal Definitions
Electrical Specifications
Absolute Maximum Ratings
The absolute maximum ratings (see Tab. 3.2: Absolute Maximum Ratings) define limitations for electrical and
thermal stresses. These limits prevent permanent damage to the Lepton7R7100C.
Operation outside maximum ratings may result in permanent damage to the device.
Parameter
Min.
Max.
Unit
Conditions
Supply voltage
-0.3
5.5
V
VDC_IN pin relative to GND
IO voltage
-0.3
4.0
V
Non-VDC_IN pin voltages relative to GND
RF input power
-
+30
dBm
Incident to pin 1 (RF)
Storage temperature
-30
+100
ºC
Humidity
-
95
% RH
Non-condensing
ESD immunity
-
2
kV
Human-body model, all I/O pads
Package moisture sensitivity
level 3
-
-
-
Lepton7R7100C from open trays must be
baked before going through a standard
solder reflow process (48 hours at 125 ºC
or 24hrs at 150 ºC)
Tab. 3.2: Absolute Maximum Ratings

HARDWARE INTERFACE - Lepton7- Technical Information Manual 14
Operating Conditions
This section describes operating voltage, frequency, and temperature specifications for the Lepton7R7100C
during operation.
Parameter
Min.
Max.
Unit
Conditions
Supply
4.75
5.25
V
VDC_IN relative to GND
Temperature
-20
+70
ºC
Ambient Temperature
Frequency
902
928
MHz
FCC part 15.247
865.6
867.6
MHz
ETSI EN 302 208 v3.3.1
Tab. 3.3: Operating Conditions
Device Functional Specifications
This section describes operating voltage, frequency, and temperature specifications for the Lepton7R7100C
during operation.
Parameter
Typ.
Unit
Description
Supply Current
Current consumed by Lepton7R7100C via VDC_IN
pin
Active mode - 5V supply
1400
mA
+30 dBm transmit power
Inventorying tags
Idle mode –low latency
45
mA
Ready to receive easy2read©protocol packets.
Lower latency to return to Active mode.
Idle mode –standard latency
5
mA
Ready to receive easy2read©packets
Standby mode
TBD
mA
GPIO activity or WKUP rising edge required to
wakeup part.
Sleep mode
TBD
μA
WKUP rising edge required to wakeup part.
Tab. 3.4: Supply Current Specifications
Parameter
Min.
Typ.
Max.
Unit
Description
Startup Time
TBD
ms
Time to receive easy2read©packets after power
supply or nRST pin initiated startup
Wakeup Time
Time to receive packets after wakeup event
Standby
TBD
ms
GPIO activity or WKUP rising edge required to
wakeup part.
Sleep
TBD
ms
WKUP rising edge required to wakeup part.
Tab. 3.5: Startup and Wakeup Time

HARDWARE INTERFACE - Lepton7- Technical Information Manual 15
UHF Gen 2 RFID Radio Specifications
Parameter
Min.
Typ.
Max.
Unit
Conditions
Frequency
902
928
MHz
See § Tab. 2.1: Lepton7 R7100C Technical
Specifications page 7
865.6
867.6
MHz
Input impedance
50
Ω
Input match
-10
dB
S11
Rx sensitivity
-85
dBm
10%PER, assuming 20 dB antenna RL @ 30
dBm output
Tab. 3.6: RF Receiver Specifications
Parameter
Min.
Max.
Unit
Notes
Tx Power
10
30
dBm
Meets FCC and equivalent regulatory
constraints
Tx Power Error
1
dB
Difference between desired Tx power and
actual Tx power
Return Loss
0
dB
No damage into open RF port at 30 dBm at
any phase angle
Frequency
865.6
867.6
MHz
ETSI EN 302 208 v3.3.1
902
928
MHz
FCC part 15.247
Tab. 3.7: RF Transmitter Specifications
Device Input and Output Specifications
Parameter
Min.
Typ.
Max.
Unit
Conditions
nRST
VIL
-0.3
0.8
V
VIH
2
3.6
V
Hysteresis voltage
400
mV
Internal pull-up resistor
14
21
25
kΩ
Reset pulse width
25
μs
WKUP
VIL
-0.3
0.8
V
VIH
2
3.6
V
Hysteresis voltage
400
mV
Internal pull-down resistor
20
35
50
kΩ
Digital inputs
VIL
-0.3
0.8
V
VIH
2
3.6
V
Hysteresis voltage
400
mV
Internal pull-down resistor
20
35
50
kΩ
Digital outputs
VOL
0.0
0.6
V
VOH
2.7
3.6
V
Drive current (sink or source)
8
mA
UART
Default baud rate
115.2
kbaud
Configurable baud rate
9.6
921.6
kbaud
Data bits
8
bits
Parity bit
None
Stop bits
1
bits
Tab. 3.8: Digital Interface Specification

HARDWARE INTERFACE - Lepton7- Technical Information Manual 16
Parameter
Min.
Typ.
Max.
Unit
Conditions
ADC (Pin 13)
Resolution
12
Bits
Conversion voltage range
0
3.3
V
Sampling rate
0.47
2.7
MSPs
Total conversion time
3.1
μsec
Power-up time
3.1
μsec
Sampling switch resistance
200
Ω
Internal sample and hold
capacitance
25
pF
Total unadjusted error
±3.5
±7.1
LSB
Offset error
±3.0
±5.6
LSB
Gain error
±1
±2.5
LSB
DNL error
±1
LSB
INL error
±2
LSB
DAC (Pin 16)
Resolution
12
Bits
Resistive load
3
kΩ
Capacitive load
100
pF
Maximum capacitive load at the
DAC_OUT pin
Output voltage range
0.1
3.15
V
DNL
±1
LSB
INL
±4
LSB
Offset
±21
mV
Gain error
±2.5
%FSR
Settling time
15
30
μsec
CLOAD < 50 pF & RLOAD > 5 kΩ
Tab. 3.9: Analog Interface Specification

LAYOUT AND COMPONENTS - Lepton7- Technical Information Manual 17
4LAYOUT AND COMPONENTS
Introduction
This section describes hardware aspects of embedded RAIN RFID readers based on the Lepton7R7100C.
PCB Layout for RF
50 Ohm Characteristic Impedance
As discussed in paragraph RF Connection page 10, a properly matched RF connection is critical to achieving
high performance with Lepton7R7100C. An improperly matched RF connection will reduce performance in
multiple ways, by both reducing the transmitted RF power, and also increasing the reflected power that
interferes with Lepton7R7100C’s receive circuitry.
When impedance is improperly matched across a node, a signal’s reflection coefficient will be proportional to
the difference between the characteristic impedances on both sides of the node divided by their sum, as
shown in the following equation.
Reflection Coefficient of a Load:
In this equation, ZL represents the characteristic impedance of the transmission line, and Z0 represents the
characteristic impedance of the Lepton7R7100C, 50 Ohms. For example, if a 40 Ohm transmission line is
used, the reflection coefficient will be = 10 / 90 = 11.1%, thus 11.1% of the power will be reflected back into
the Lepton7R7100C, and only 88.9% of the power will be transmitted.
Lepton7R7100C is designed to connect to a 50-Ohm characteristic impedance load. The connection between
the Lepton7R7100C module and its antennas should all be designed for a 50 Ohm characteristic impedance.
Because the RF connection is made via PCB traces, this requires carefully designing the PCB layout.
PCB trace characteristic impedance depends on quite a few variables, only some of which can easily be
controlled by the PCB designer. The two main categories of variables are the PCB geometry, and material
properties. PCB geometry includes both the transmission line type, be it microstrip, stripline, or others, and
also the specific dimensions of the forward and return paths and the adjacent dielectrics. Transmission line
styles are shown in Fig. 4.1: PCB Transmission Line Types page 17. Material properties to note include the
dielectric constant of the dielectrics in the PCB, and the conductivity of the conductor used.
Fig. 4.1: PCB Transmission Line Types

LAYOUT AND COMPONENTS - Lepton7- Technical Information Manual 18
In most PCB designs, many of the parameters of the PCB are already set, such as dielectric thickness and
constant, trace conductivity and weight, etc. Usually, the only variables that can be easily modified are the
style of transmission line, and its dimensions. The most common, and recommended PCB transmission line
scheme is to use a microstrip on the top or bottom layer of the PCB, with a ground plane on the layer
immediately adjacent as a return path. The width of this microstrip can then be varied to achieve the desired
characteristic impedance. Care should be taken to ensure that the microstrip trace has enough current
carrying capacity. This requires designing a trace that is heavy enough to withstand the heat generated by
power losses due to the resistance of the trace.
There are many online resources and tools designed to assist in designing PCB transmission lines with the
correct characteristic impedances. For example, the TXLine tool from National Instruments is very useful for
performing these calculations automatically. There is also an online calculator on eeweb.com. These tools will
require information about the PCB layout and also PCB characteristics, which should be obtained from the
PCB manufacturer.
Package and Assembly Information
This section provides mechanical drawings and critical dimensions needed for PCB layout and housing
design, as well as SMT assembly information.
Package Mass
The mass of the Lepton7R7100C module is roughly 5.4 grams.
Package Dimensions
Package dimensions are shown in the following figure:
Fig. 4.2: Package Dimensions, Top, Front, and Side Views
Download the Lepton7R7100C Technical drawing at Lepton7R7100C web page (Documents section).

LAYOUT AND COMPONENTS - Lepton7- Technical Information Manual 19
PCB Footprint
Recommended footprint copper and pastemask dimensions are shown in the following:
Fig. 4.3: Recommended Etched Copper Footprint –All Pads
SMT Reflow Information
The solder manufacturer’s recommended reflow profile is shown in the following figure:
Fig. 4.4: Recommended Solder Reflow Profile for the Lepton7R7100C

LAYOUT AND COMPONENTS - Lepton7- Technical Information Manual 20
Moisture Sensitive Level 3 (MSL 3)
CAEN RFID srl follows JEDEC standards for moisture classifications. The Lepton7R7100C RFID reader is
classified as MSL 3.
Y
Warning: The damaging effects of moisture absorbed in semiconductor packages during SMT
assembly are known. Pay attention to the next paragraphs and follow the instructions to avoid
problems.
MSL 3 Handling at PCB Assembly
The Lepton7R7100C package is moisture sensitive and needs to be handled within proper MSL 3 guidelines
to avoid damage from moisture absorption and exposure to solder reflow temperatures that can result in yield
and reliability degradation.
A. During PCB Assembly
1. Devices are baked and dry-packed before shipment from CAEN RFID. The packing uses a
Moisture Barrier Bag (MBB). A Humidity Indicator Card (HIC) and drying desiccant are included
inside the MBB. A MSL 3 label is attached to caution that the bag contains moisture sensitive
devices.
2. Shelf life of devices in a sealed bag is 12 months at <40ºC and <90% room humidity (RH).
3. Upon opening of MBB, the HIC should be checked immediately; devices require baking before
board mounting if the HIC is >10% when read at 23ºC ± 5ºC.
4. After MBB is opened, devices should go through reflow for board assembly within 168 hours at
factory conditions of <30ºC/60% RH, or stored at <10% RH. If both conditions are not met,
baking is required before board mounting.
5. If baking is required, devices should be baked for a minimum of 48 hours at 125ºC or 24 hours
at 150°C.
B. Handling Unused Devices
1. Any unused devices after the MBB have been opened for more than 168 hours or not stored at
<10% RH should be baked before any subsequent reflow and board assembly.
2. Re-baking should be done for a minimum of 48 hours at 125ºC or 24 hours at 150°C.
3. Unused devices can either be baked and dry-packed first before storage, or they can be baked
just before the next board assembly. It is recommended that the former be practiced as it helps
to prevent operator error from re-using devices without baking. In both cases, the re-packed
materials should follow the guidelines in section A.
C. Reworking a Device on a PCB
1. Before a device is removed from the module, the module must first be baked.
2. Baking should be done for a minimum of 48 hours at 125ºC or 24 hours at 150°C.
3. It is recommended that during removal, localized heating be used, and the maximum body
temperature of device should not exceed 200ºC.
4. The replacement device should not exceed the specified floor life of 168 hours.