Telit Wireless Solutions BLUEMOD+S42/AI/CEN User manual

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BlueMod+S42
HW User Guide
1VV0301303 Rev. 11 –2021-05-06
Telit Technical Documentation

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APPLICABILITY TABLE
PRODUCTS
BLUEMOD+S42/AI/CEN
BLUEMOD+S42/AI/ATEX
BLUEMOD+S42/AI/ADC/LUA
BLUEMOD+S42/AI/ADC/TWI

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CONTENTS
APPLICABILITY TABLE 2
CONTENTS 3
1. INTRODUCTION 8
1.1. Scope 8
1.2. Audience 8
1.3. Contact Information, Support 8
1.4. Symbol Conventions 9
1.5. Related Documents 9
2. GENERAL PRODUCT DESCRIPTION 10
2.1. Feature Summary 10
2.2. Applications 11
2.3. General Cable Replacement 11
2.3.1. Industry 11
2.3.2. POS/Advertising 11
2.3.3. Healthcare and Medical 11
2.3.4. Sports and Fitness 12
2.3.5. Entertainment 12
2.4. Block Diagram 12
3. APPLICATION INTERFACE 13
3.1. Power Supply 13
3.1.1. Power-up Slew-Rate 14
3.2. Reset 14
3.3. Serial Interface 15
3.3.1. Serial Interface HW Configuration for Power Management 16
3.3.1.1. Wake-Up Sources AT+SYSTEMOFF 17
3.3.1.2. Serial Interface for UICP Power Management 18
3.3.1.3. Serial Interface without UICP Power Management 19
3.3.2. 4-Wire Serial Interface 20
3.3.3. UART Example Circuits 22
3.3.4. Baud Rate Deviation 23

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3.3.5. Dynamic I/O Signal Type Changes Depending on UICP Status
23
3.3.6. Additional I/O Signals for Serial Interface Functionality 24
3.3.6.1. Hang-up via GPIO Signal 24
3.3.6.2. GPIO’S IO [A, B, C, D] 24
3.4. GPIO Interface 24
3.5. I2C Interface 25
3.6. SPI Serial Peripheral Interface 25
3.7. Bluetooth Radio Interface 26
3.8. NFC Function 26
3.8.1. NFCT Antenna Recommendations 26
3.8.2. Power Back Feeding 27
3.9. Slow Clock Interface 27
3.9.1. 32,768 kHz Crystal Oscillator Specification (32k XOSC) 28
3.9.2. Connection of an External 32,768 kHz Crystal 28
3.10. Test Mode 29
3.11. Operating in a Power-Switched Environment 30
3.12. Serial Wire Debug Interface 31
3.13. DC/DC Converter 31
3.14. Analog/Digital Converter (ADC) 31
4. MODULE PINS 34
4.1. Pin Numbering 34
4.2. General Pin Description 35
4.3. Application Specific CEN Pin Configuration 36
4.4. Application Specific ADC/TWI Pin Configuration 37
4.5. Application Specific ADC/LUA Pin Configuration 39
4.6. Handling of Unused Signals 41
5. ELECTRICAL CHARACTERISTICS 42
5.1. Absolute Maximum Ratings 42
5.2. Operating Conditions 42
5.3. Environmental Requirements 42
5.4. DC Parameter 42

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5.4.1. General Purpose I/O (GPIO) 43
5.4.2. EXT-RES# 43
5.4.3. Analog Digital Converter (ADC) 43
5.4.3.1. Analog ADC Input AIN 43
5.5. Power Consumption and Power-Down Modes 45
5.5.1. Power Consumption BlueMod+S42/AI CEN FW 45
5.5.1.1. Power Consumption BlueMod+S42/AI 45
5.5.1.2. Power Consumption BlueMod+S42/AI/ATEX 47
5.6. RF Performance 49
5.6.1. BLE Receiver 49
5.6.2. BLE Transmitter 50
5.6.3. Antenna-Gain and Radiation Pattern 51
5.7. Power-Up Time 52
6. MECHANICAL CHARACTERISTICS 53
6.1. Dimensions 53
6.2. Recommended Land Pattern 53
6.3. Re-flow Temperature-Time Profile 54
6.4. Placement Recommendation 54
6.5. Housing Guidelines 55
6.6. Antenna Issues 55
6.7. Safety Guidelines 56
6.8. Cleaning 56
7. APPLICATION DIAGRAM 57
8. COMPLIANCES 58
8.1. Declaration of Conformity CE 58
8.2. FCC Compliance 58
8.2.1. FCC Grant 59
8.2.2. FCC Statement 60
8.2.3. FCC Caution 60
8.2.4. FCC Warning 60
8.2.5. FCC RF-exposure Statement 60

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8.2.6. FCC Labeling Requirements for the End Product 61
8.3. IC Compliance 61
8.3.1. IC Grant 62
8.3.2. IC Statement 64
8.3.3. IC Caution 64
8.3.4. IC RF-exposure Statement 64
8.3.5. IC Labeling Requirements for the End Product 65
8.3.6. IC Label Information BlueMod+S42 65
8.4. KC Certification 66
8.4.1. KC Certificate 66
8.4.2. KC Mark 67
8.5. MIC Certification 68
8.5.1. MIC Certificate 69
8.6. Anatel Certification 70
8.7. Australian RCM Mark 71
8.8. Bluetooth Qualification 72
8.9. RoHS Declaration 73
9. PACKING 74
9.1. Tape&Reel Packing 74
9.1.1. Tape 75
9.1.2. Reel 75
9.2. Tray Packing 76
9.2.1. Module Orientation 76
9.2.2. Tray Dimensions 76
9.3. Moisture Sensitivity Level 76
10. EVALUATION KIT 77
11. PRODUCT AND SAFETY INFORMATION 78
11.1. Copyrights and Other Notices 78
11.1.1. Copyrights 78
11.1.2. Computer Software Copyrights 78
11.2. Usage and Disclosure Restrictions 79

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11.2.1. License Agreements 79
11.2.2. Copyrighted Materials 79
11.2.3. High Risk Materials 79
11.2.4. Trademarks 80
11.2.5. 3rd Party Rights 80
11.2.6. Waiver of Liability 80
11.3. Safety Recommendations 81
12. GLOSSARY 82
13. DOCUMENT HISTORY 83

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1. INTRODUCTION
1.1. Scope
This document provides information how the BlueMod+S42/AI can be integrated into
customer systems. It addresses hardware specifications of the BlueMod+S42/AI and
requirements of the hardware environments for the BlueMod+S42/AI.
Note/Tip: The description text “BlueMod+S42” refers to all modules
listed in the applicability table.
1.2. Audience
This document is intended for Telit customers, especially system integrators, about to
implement Bluetooth modules in their application.
1.3. Contact Information, Support
For general contact, technical support services, technical questions and report of
documentation errors contact Telit Technical Support at:
• TS[email protected]
• TS[email protected]
• TS[email protected]
• TS[email protected]
• TS[email protected]
Alternatively, use:
https://www.telit.com/contact-us/
For detailed information about where you can buy the Telit modules or for
recommendations on accessories and components visit:
https://www.telit.com
Our aim is to make this guide as helpful as possible. Keep us informed of your comments
and suggestions for improvements.
Telit appreciates the user feedback on our information.

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1.4. Symbol Conventions
Danger: This information MUST be followed or catastrophic
equipment failure or personal injury may occur.
Warning: Alerts the user on important steps about the module
integration.
Note/Tip: Provides advice and suggestions that may be useful when
integrating the module.
Electro-static Discharge: Notifies the user to take proper grounding
precautions before handling the product.
Table 1: Symbol Conventions
All dates are in ISO 8601 format, that is YYYY-MM-DD.
1.5. Related Documents
•[1] Nordic: nRF52_Series_Reference_Manual
•[2] Nordic: nRF52832_PS v1.x.pdf (Product Specification)
•[3] BlueMod+S42/Central AT Command Reference, 80512ST10771A
•[4] BlueMod+S42 Software User Guide, 1VV0301318
•[5] UICP_UART_Interface_Control_Protocol, 30507ST10756A
•[6] BlueMod+S42 Testmode Reference, 80512NT11496A
•[7] Bluetooth SIG Core Specification V4.2
•[8] BlueMod+S42/Central AT Command Reference 80512ST10771A
•[9] BlueMod+S42/ADC/TWI AT Command Reference 80512ST10874A
•[10] BlueMod+S42/ADC/LUA AT Command Reference 80512ST10860A
•[11] BlueMod+S42 Lua API Documentation 30512ST10861A

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2. GENERAL PRODUCT DESCRIPTION
2.1. Feature Summary
•Bluetooth specification V4.2 compliant
•Supports Bluetooth low energy
•Fully qualified Bluetooth V4.2 Single Mode LE
•CE certified
•FCC and IC certified
•Nordic nRF52832 inside
•Fast Connection Setup
•RF output power -20 up to +4dBm EIRP
•RF output power -40dBm EIRP in Whisper Mode
•RSSI detector on board
•High sensitivity design
•Supply voltage range 1,7V to 3,6V
•Internal crystal oscillator (32 MHz)
•LGA Surface Mount type. BlueMod+S42: 17 x 10 x 2.6 mm3
•Pin compatible to Telit BlueMod+S BLE and BlueMod+SR dual mode module
•Shielded to be compliant to FCC full modular approval
•Flexible Power Management
•128-bit AES encryption
•NFC peripheral communication signal interface type A with 106 kbps bit rate
•High-speed UART interface
•I2C Master
•SPI Master/Slave interface
•Low power comparator
•Real Time Counter
•Up to 19 digital IO’s for individual usage by embedded software
•Up to 8 analog inputs for individual usage by embedded software

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•8/9/10/12bit ADC
•Arm® CortexTM-M4F core for embedded profiles or application software
•Manufactured in conformance with RoHS2
•Operating temperature -40 ... +85 °C
•Weight: 0,7 g
2.2. Applications
The BlueMod+S42 is designed to be used in low power applications, like sensor devices.
Some typical applications are described in this chapter.
Supported profiles are:
•Terminal I/O
•GATT based LE-profiles
Note/Tip: Support for any additional profile is possible on request.
2.3. General Cable Replacement
In case there is no standardized application specific profile available the BlueMod+S42
offers Telit’s Terminal I/O profile, which allows transparent data transfer over UART and
supports Secure Simple Pairing, making the pairing process easy and the connection
secure. Terminal I/O is available for iOS and Android as well as implemented in Telit’s
dual mode module BlueMod+SR.
2.3.1. Industry
BlueMod+S42 can be used to monitor and control motors, actuators, values, and entire
processes.
2.3.2. POS/Advertising
BlueMod+S42 supports iBeacon or similar applications.
2.3.3. Healthcare and Medical
Usage of Bluetooth is aimed mainly at devices that are used for monitoring vital data.
Typical devices are blood glucose meter, blood pressure cuffs and pulse ox meters.

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Bluetooth BR/EDR and low energy were chosen by the Continua Health Alliance as
transports for interoperable end to end communication.
2.3.4. Sports and Fitness
In the sports and fitness segment the BlueMod+S42 is used in devices for positioning as
well as monitoring vital data. Typical devices in this market are heart rate monitors, body
temperature thermometers, pedometers, cadence meters, altimeter, positioning / GPS
tracking and watches displaying information from sensors.
2.3.5. Entertainment
Bluetooth technology is already used in a wide variety of devices in the entertainment
sector, namely set-top boxes / gaming consoles. BlueMod+S42 is especially suited for
use in remote controls, gaming controller and wireless mouse/keyboard applications.
2.4. Block Diagram
nRF52832
VSUP
BlueMod+S42/AI
RESET
I2C
UART
SPI
1 2
up to 7
3
GND
3.0V
32MHz
opt. 32kHz
Serial Wire Debug
onboard
antenna
2
GPIO
up to 19
Analog In
up to 6
NFC-Antenna
2
32,768kHz
optional
Figure 1: BlueMod+S42/AI Block Diagram

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3. APPLICATION INTERFACE
3.1. Power Supply
BlueMod+S42 require a power supply with the following characteristics:
Typical: 3,0VDC, min.: 1,7VDC, max.: 3,6VDC, thereby delivering > 25 mA peak
BlueMod+S42 is designed to be powered from 3V coin cell batteries e.g. CR2032 directly,
or any other power source complying with the given requirements. For optimal
performance, a stable supply is recommended. Furthermore, it is recommended to place
a capacitor in parallel to the CR2032 3V coin cell battery in order to prolong battery
lifetime, by compensating the effects of the rising source resistance of the battery to
pulsed loads. Since the isolation resistance of this capacitor will discharge the battery in
a not insignificant scale, the capacitor should be chosen under consideration of the
following rules:
•Capacitance as small as necessary
•Nominal voltage as high as possible
•Case size as large as possible
•Use X7R instead of X5R
In case of using an NFC antenna in conjunction with batteries attend to chapter 3.8.2
Power Back Feeding.
BlueMod+S42
XC6209F-3.3
E-6,F-6
VSUP
GND:
A-7,E-7,F-7,B-[5:8],
C-[5:8],D-8,E-8,F-8
1µ + 100n
1µ
VOUT
VSS
VIN
CE
5 1
3
2
+5VDC
Figure 2: BlueMod+S42 Example Power Supply with LDO

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3.1.1. Power-up Slew-Rate
Parameter
Min
Max
Unit
VSUP rise time rate (1)
0
60
ms
(1) 0V to 1,7V
Table 2: Power up Rise Time Requirements
3.2. Reset
BlueMod+S42 are equipped with circuitry for generating reset from three sources:
•A reset is held active, when VSUP falls below the threshold of the brownout
detector (VBOR = 1,2V … 1,7V), and is released when VSUP rises above VBOR +
VHYST .
The brownout detector also holds the reset active during power up, until VSUP >
VBOR.
•A reset is generated, when VSUP is > VBOR and increases 300 mV or more, within
300 ms or less.
•By holding pin B-1 (EXT-RES#) at ≤VSUP*0,25V for tHOLDRESETNORMAL ≥0,2µs,
an external reset ( pin reset ) is generated. EXT-RES# may be left open if not used.
This pin has:
oFor all the variants except BlueMod+S42/AI/ATEX a fixed internal pull-up
resistor (RPU = 11kΩ... 16kΩ) and a series resistor of 470Ω
oFor BlueMod+S42/AI/ATEX a fixed internal pull-up resistor (RPU = 11kΩ...
16kΩ). A series resistor less than 560Ωshould be added externally.
BlueMod+S42
E-6,F-6
VSUP
GND
+3V3
EXT-RES# B-1
Reset-Switch is optional
Please Note: EXT-RES# of BlueMod+S42 has approx. 13k internal pullup.
Reset signal is optional
Host MCU
GPIO
VDD
Figure 3: BlueMod+S42 Example Reset

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The following table shows the pin states of BlueMod+S42 during reset active.
Pin Name
State: BlueMod+S42
EXT-RES#
Input with pull-up (1)
XL-IN
Input floating (disconnected)
XL-OUT
Input floating (disconnected)
UART-TXD
Input floating (disconnected)
UART-RXD
Input floating (disconnected)
UART-RTS#
Input floating (disconnected) with pull-up resistor 470kΩ(2)
UART-CTS#
Input floating (disconnected)
IUR-OUT#
Input floating (disconnected)
IUR-IN#
Input floating (disconnected)
GPIO[0:14]
Input floating (disconnected)
TESTMODE#
Input floating (disconnected)
BOOT0
Input floating (disconnected)
SWDIO
Input with pull-up (1)
SWCLK
Input with pull-down (1)
(1) pull-up, pull-down: RPU, RPD is typ. 13kΩ(11kΩto 16kΩ)
(2) a discrete resistor is used
Table 3: Pin States during Reset
The pin states as indicated in Table 3 are kept until hardware initialization has started.
3.3. Serial Interface
The serial interface of BlueMod+S42 is a high-speed UART interface supporting RTS/CTS
flow control and interface-up/down mechanism according to the UICP+ protocol (refer to
[5] ).
Electrical interfacing is at CMOS levels (defined by VSUP; see chapter 5.4.1).
Transmission speeds are 9600 –921600 bps and 1Mbps (asynchronous).
Character representation: 8 Bit, no parity, 1 stop bit (8N1).
Hardware flow-control with RTS and CTS (active low).
Note/Tip: Transmission speed may be limited by firmware. See
corresponding AT command reference [3] for further information.
Note/Tip: Connecting Bluetooth module and host CPU via an UART
interface.

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BlueMod+Sx
IUR-IN / DTR
IUR-OUT / DSR
IUC-IN / RTS
IUC-OUT / CTS
Rx-Data
Tx-Data
Host
DTR / IUR-IN
DSR / IUR-OUT
RTS / UIC-IN
CTS / IUC-OUT
Rx-Data
Tx-Data
Figure 4: Connection BlueMod+Sx to Host
All signal pairs,
•TX-Data / RX-Data,
•(IUC_IN/RTS) / (IUC-OUT/CTS)
•(IUR-IN/DTR) / (IUR-OUT/DSR)
must be connected crosswise between the 2 devices.
Note/Tip: It is strongly recommended to use hardware flow control
in both directions. Not using flow control can cause a loss of data
3.3.1. Serial Interface HW Configuration for Power Management
Note/Tip:
It is strongly recommended NOT to switch the module power supply
on/off while other parts of the circuitry stay powered. This mostly
leads to hardly controllable back-feeding issues. Back-feeding
occurs due to connected signal line(s) being >0,3V while the module
power is switched off. Then the I/O protection diodes, integrated in
the I/O ports of the BT IC, will feed the VSUP “backwards”, which
means that the modules power supply is fed via the I/O lines instead
via the power supply. Due to the ultra-low power design a few µAmps
are enough to raise VSUP to an undefined state, which may cause a
hang-up deadlock when then power is switched on again.
Any I/O pin at a voltage > 0,3V while the supply VSUP is at 0V violates
the abs. max. ratings given in chapter 5.1 Absolute Maximum
Ratings.
It is instead recommended to use the advanced power management
features, which may reduce the supply current to 300nA.

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Deep Sleep power saving could be achieved by using the AT+SYSTEMOFF command.
Wake-up from deep sleep after AT+SYSTEMOFF always includes a reset cycle and a loss
of the previous operation environment. If it is desired to keep the operation environment
during power down UICP SW should be implemented in the host CPU.
If using the AT+SYSTEMOFF command in combination with wake-up via GPIO, a host
could wake-up the BlueMod+Sx using the UICP schemes. Alternatively, the wake-up
source ext. RESET could be configured, which results in the least possible current
consumption.
See chapters 3.3.5 Dynamic I/O Signal Type Changes Depending on UICP Status.
UART
GND
UART
BlueMod+Sx
Host
GPIOxEXT-RES#
Figure 5: Host wake-up from deep-sleep via RESET
3.3.1.1. Wake-Up Sources AT+SYSTEMOFF
The wake-up sources are FW dependent and programmable. For detailed information
please see corresponding FW documentation. The following table gives a rough overview.
WAKE-UP
SOURCE
FW CEN
FW ADC/TWI
FW ADC/LUA
Deep Sleep
Current
PIN RESET#
YES
YES
YES
0.3µA
CTS#
YES
YES 1)
YES 1)
1.2µA
IUR-IN#
YES 2)
YES 2)
NO
1.2µA
HANGUP#
YES
NO
NO
1.2µA
DIOx
NO
YES 3)
YES 3
1.2µA
Note:
1) Only available if UART is active
2) Only available if UICP is active
3) Only if DIOx is enabled as input
Table 4: Wake-Up Sources AT+SYSTEMOFF

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3.3.1.2. Serial Interface for UICP Power Management
A substantially saving of power during idle phases can be achieved (see 5.5.1) when the
UICP protocol is used (refer to [5] ). This protocol should be implemented on the host side
as well. Signals IUR-IN# and IUR-OUT# should be connected to the host and may be
mapped, if connected to a standard RS232 COM port, to DSR and DTR (see Figure 10).
Using UICP reduces the supply current from the mA range to the µA range in idle phases
which are normally the highest percentage of the use time, depending on the use case
scenario. This comes at the cost of 2 additional I/O lines, whereas 1 I/O line has been
saved by not switching the module power on/off. Therefore, only 1 additional I/O line is
required to make the power management much smarter and reliable.
Further advantages compared to SYSTEMOFF
•The Module can maintain volatile configuration while in power down state
•The Module can be visible and connectable (advertisements enabled) while in
power down state
•The Module can be connected (BT connected, no data exchange) while in power
down state
There are 2 signals changing functionality depending on the UICP state.
•IUC_OUT#/RTS# and IUC_IN#/CTS# become RTS#/CTS# after wake-up
•IUC_OUT#/RTS# and IUC_IN#/CTS# become IUC_OUT#/IUC_IN# after power-
down
Please refer to the UICP specification [5]for detailed information.
UART-TXD
GND
UART-RXD
IUC_IN# / CTS#
UART-RXD
UART-TXD
BlueMod+Sx
Host
RTS# / IUC_OUT#
CTS# / IUC_IN#
IUC_OUT# / RTS#
IUR_OUT#
IUR_IN# IUR_OUT#
IUR_IN#
Figure 6: UART Interface with UICP Signals 7-wire (incl. GND)

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If I/O line availability at the host side is extremely tight, 2 I/O lines could be saved by using
the following scheme. This would come at the cost of
•The host is not allowed to enter sleep mode.
•The host must accept in coming data at all times and is not able to stop the
BlueMod+Sx sending data. This may be difficult to control for all scenarios and
adds the risk that data gets lost.
•The host doesn’t implement UICP, but wake-up BT via GPIO
UART-TXD
GND
UART-RXD
IUC_IN# / CTS#
UART-RXD
UART-TXD
BlueMod+Sx
Host
RTS#
CTS#
IUC_OUT# / RTS#
IUR_OUT#
IUR_IN#BM+Sx-WKUP
Figure 7: 5-Wire (incl. GND) Interface supporting UICP (min. signals needed)
3.3.1.3. Serial Interface without UICP Power Management
If power management with maintaining the operational environment is not necessary,
the serial interface could be designed with less I/O lines.
This saves 2 I/O lines at the cost that dynamic power management with maintaining the
operation environment cannot be used. UICP has to be disabled.

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UART-TXD
GND
UART-RXD
IUC_IN# / CTS#
UART-RXD
UART-TXD
BlueMod+Sx
Host
RTS#
CTS#
IUC_OUT# / RTS#
IUR_OUT#
IUR_IN#
Figure 8: UART Interface without UICP Signals (5-wire incl. GND)
Note/Tip: To support operation with the BlueMod+Sx pin CTS# left
open, a pulldown resistor (typ. 13kΩ) is programmed to this pin if
UICP is disabled.
Therefore, if AT+SYSTEMOFF is issued while UICP is disabled, it is
necessary that the host keeps CTS# at logic low or leaves this pin
floating.
Otherwise the supply current drawn in the deep sleep mode
increases by VSUP/13kΩ, which would be at 3V 231µA, 770 times the
expected 0,3µA. This would reduce the lifetime of a coin cell
significantly.
3.3.2. 4-Wire Serial Interface
If the host in question is sufficiently fast, a 4-wire (incl. GND) scheme may be successful.
Connect the serial lines UART-RXD, UART-TXD as well as UART-RTS# and GND; leave
UART-CTS# open. The host is required to stop sending data within a short time after de-
assertion of UART-RTS# (there is room for up to 4 more characters at the time RTS#
drops).