AMS AS621 Series User manual

User Guide
UG000452
AS621x
Eval Kit
AS6212-EK, AS6214-EK & AS6218-EK
v1-01 •2019-Oct-08

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AS621x
Content Guide
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Content Guide
1Introduction....................................3
1.1 Kit Content.................................................... 3
1.2 Ordering Information .................................... 3
2Getting Started...............................4
3Hardware Description....................5
3.1 Hardware Architecture .................................5
3.2 AS621x Configuration .................................. 6
3.3 Power Supply and Connections................... 7
4Software Description.....................8
4.1 Index Register.............................................. 8
4.2 Temperature Register...................................9
5Schematics, Layers and BOM .... 11
5.1 Schematics................................................. 11
5.2 Layout and Board Dimensions................... 11
5.3 Bill of Materials........................................... 13
6Revision Information................... 14
7Legal Information ........................ 15

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AS621x
Introduction
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1 Introduction
The AS621x Eval Kit is a small PCB allowing a simple and quick evaluation of the AS621x digital
temperature sensors without the need to design a custom PCB. This small form factor board is fully
assembled with the AS621x temperature sensor and its necessary external components.
1.1 Kit Content
This kit contains following material listed in Figure 1
Figure 1:
Kit Content
Pos.
Item
Comment
1
AS621x-EK
Eval Kit
1.2 Ordering Information
Figure 2:
Ordering Code
Ordering Code
Description
AS6212-EK
AS6212 Eval Kit up to 0.2 °C accuracy
AS6214-EK
AS6214 Eval Kit up to 0.4 °C accuracy
AS6218-EK
AS6218 Eval Kit up to 0.8 °C accuracy

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AS621x
Getting Started
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2 Getting Started
The AS621x Eval Kit is ideal for rapid setup of a digital temperature sensor. To get started connect the
board to your microcontroller as described in Figure 4. Add a command in your source code to request
two bytes from the selected I²C address. Finally convert the returned data as described in chapter 4.2
to get the actual temperature value.
Figure 3:
Eval Kit

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Hardware Description
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3 Hardware Description
The P1 connector does provide all relevant signals, which can be easily wired to a microcontroller and
to the power supply.
Figure 4:
Eval Kit Pin-Out
Pin
Symbol
Description
Info
1
SCL
I²C clock
Use R1 if pull-up is required
2
SDA
I²C data
Use R2 if pull-up is required
3
GND
Ground
4
VDD
Power supply
According datasheet
5(1)
ALERT
Digital output pin
Alert interrupt output
(1) Do not connect pin 5 to VSS. This pin should only be used for the ALERT functionality
3.1 Hardware Architecture
Figure 5:
AS621x Eval Kit
R1, R2 and R3 are pull-up resistors for the I²C interface and the ALERT pin. Depending on the
application, it is recommended to either populate the decoupling capacitor C1.

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3.2 AS621x Configuration
With the address selector, it is possible to choose the I²C address of the device. The included jumpers
are an easy way of setting the I²C address of the sensor. Both address selectors must not be left
open.
Figure 6:
I²C Address
Jumper
Settings
Address
Selector
ADD0
Address
Selector
ADD1
Device Address
Binary HEX
GND
SCL
100 0100
0x44
VDD
SCL
100 0101
0x45
SDA
SCL
100 0110
0x46
SCL
SCL
100 0111
0x47
GND
ALERT
functionality
100 1000
0x48
VDD
ALERT
functionality
100 1001
0x49
SDA
ALERT
functionality
100 1010
0x4A
SCL
ALERT
functionality
100 1011
0x4B

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3.3 Power Supply and Connections
The PCB has to be connected to an external microcontroller. P1 is populated with a 1x5 pin header
and is required for power supply as well as I²C communication. In addition to that, it can be used to
monitor the interrupt status via pin 5 (IRQ).
Figure 7:
MCU and AS621x Connections

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AS621x
Software Description
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4 Software Description
The AS621x has 4 data registers. With the use of the index register, it is possible to address the
specific data register. When powered up the address register is set to 0x0.
Figure 8:
Data Registers
For additional configuration settings, the Config register (0x1) has to be addressed. Please refer to the
datasheet for details.
Figure 9:
Configuration Register
Address
Symbol
Register
Description
0x0
TVAL
Contains the temperature value
0x1
CONFIG
Configuration Register
Configuration settings of the
temperature sensor
0x2
TLOW
TLOW Register
Low temperature threshold value
0x3
THIGH
THIGH Register
High temperature threshold value
4.1 Index Register
The index register contains 8-bit, but only D0 and D1 are used.

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Software Description
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Figure 10:
Index Register
Bit
D7
D6
D5
D4
D3
D2
D1
D0
Value
0
0
0
0
0
0
Address Bits
4.2 Temperature Register
Figure 11:
Temperature Register
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
T15
T14
T13
T12
T11
T10
T9
T8
T7
T6
T5
T4
T3
T2
T1
T0
MSB Byte
LSB Byte
The temperature register contains the digitally converted temperature value. It consists of 2 bytes and
can be converted according to the following formula:
Positive values= |Value| / LSB
Negative values= Complement( |Value| / LSB ) + 1
Example +75°C
75°C/ 0.0078125 °C=9600=Binary 0010 0101 1000 0000=Hex 2800
Example -40°C
|−40°𝐶/0.0078125 °𝐶 + 1 = 5120 + 1 = 𝐵𝑖𝑛𝑎𝑟𝑦 0001 0100 0000 0000 + 1 = 1110 1100 0000 0000 =
𝐻𝑒𝑥 𝐸𝐶00

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Figure 12
Temperature Conversion Examples
Temperature (°C)
Digital Output (Binary)
Digital Output (Hex)
100.0
0011 0010 0000 0000
3200
75.0
0010 0101 1000 0000
2580
50.0
0001 1001 0000 0000
1900
25.0
0000 1100 1000 0000
0C80
0.125
0000 0000 0001 0000
0010
0.0078125
0000 0000 0000 0001
0001
0.0
0000 0000 0000 0000
0000
-0.0078125
1111 1111 1111 1111
FFFF
-0.125
1111 1111 1111 0000
FFF0
-25.0
1111 0011 1000 0000
F380
-40.0
1110 1100 0000 0000
EC00