Würth Elektronik 2521020222501 User Guide
TEMPERATURE SENSOR IC
WSEN-TIDS
USER MANUAL
2521020222501
VERSION 1.0
FEBRUARY 7, 2020
Revision history
Manual
version
1.0
Notes
• Initial release of the manual
Date
February 2020
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 1
Abbreviations
Abbreviation Description
ASIC Application Specific Integrated Circuit
BDU Block Data Update
ESD Electrostatic Discharge
HBM Human Body Model
IC Integrated Circuit
I2C Inter Integrated Circuit
LSB Least Significant Bit
MSB Most Significant Bit
ODR Output Data Rate
PCB Printed Circuit Board
RH Relative humidity
UDFN Ultra-Dual Flat No Lead
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 2
Contents
1 Introduction 5
1.1 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.2 Key features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.3 Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 Sensor specifications 6
2.1 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Temperature sensor specification . . . . . . . . . . . . . . . . . . . . . . . . 7
2.4 Electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3 Pinning information 9
3.1 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4 Digital interface 10
4.1 General characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.2 SDA and SCL logic levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.3 Communication phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.3.1 Idle state . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.3.2 START(S) and STOP(P) condition . . . . . . . . . . . . . . . . . . . 11
4.3.3 Data validity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.3.4 Byte format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.3.5 Acknowledge(ACK) and No-Acknowledge(NACK) . . . . . . . . . . 12
4.3.6 Slave address for the sensor . . . . . . . . . . . . . . . . . . . . . . 13
4.3.7 Read/Write operation . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.4 I2C timing parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5 Application circuit 17
6 Quick start guide 18
6.1 Powe-up sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.2 Communication with host controller . . . . . . . . . . . . . . . . . . . . . . . 18
6.3 Sensor operation: single conversion mode . . . . . . . . . . . . . . . . . . . 19
6.4 Sensor operation: continuous mode . . . . . . . . . . . . . . . . . . . . . . 20
6.5 Modes of operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.6 Power-down mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.7 Single conversion mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.8 Continuous mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
7 Reading temperature data 24
8 Interrupt functionality 26
8.1 Interrupt output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
9 Register map 28
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 3
10 Register description 29
10.1 DEVICE_ID (0x01) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
10.2 T_H_LIMIT (0x02) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
10.3 T_L_LIMIT (0x03) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
10.4 CTRL (0x04) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
10.5 STATUS (0x05) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
10.6 DATA_T_L (0x06) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
10.7 DATA_T_H (0x07) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
10.8 SOFT_RESET (0x0C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
11 Physical dimensions 34
11.1 Sensor drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
11.2 Footprint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
12 Manufacturing information 36
12.1 Moisture sensitivity level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
12.2 Soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
12.2.1 Reflow soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
12.2.2 Cleaning and washing . . . . . . . . . . . . . . . . . . . . . . . . . 38
12.2.3 Potting and coating . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
12.2.4 Storage conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
12.2.5 Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
13 Important notes 40
13.1 General customer responsibility . . . . . . . . . . . . . . . . . . . . . . . . . 40
13.2 Customer responsibility related to specific, in particular safety-relevant ap-
plications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
13.3 Best care and attention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
13.4 Customer support for product specifications . . . . . . . . . . . . . . . . . . 40
13.5 Product improvements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
13.6 Product life cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
13.7 Property rights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
13.8 General terms and conditions . . . . . . . . . . . . . . . . . . . . . . . . . . 41
14 Legal notice 42
14.1 Exclusion of liability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
14.2 Suitability in customer applications . . . . . . . . . . . . . . . . . . . . . . . 42
14.3 Usage restriction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
15 License terms for Würth Elektronik eiSos GmbH & Co. KG sensor product
software and source code 44
15.1 Limited license . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
15.2 Usage and obligations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
15.3 Ownership . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
15.4 Disclaimer of warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
15.5 Limitation of liability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
15.6 Applicable law and jurisdiction . . . . . . . . . . . . . . . . . . . . . . . . . . 45
15.7 Severability clause . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
15.8 Miscellaneous . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 4
1 Introduction
This user manual describes a silicon-based, high precision digital temperature IC sensor
embedded with an analog and digital signal processing unit. The integrated ASIC with digital
I2C interface provides a factory calibrated 16-bit temperature data to the host controller. The
operating voltage of the sensor from 1.5 V to 3.6 V and the typical current consumption of
1.75 µA makes it suitable for battery operated applications. Compact 6-lead UDFN package
with a form factor of 2.0×2.0×0.5 mm provides a fast thermal response. The exposed pad at
the bottom provides better temperature match with the surrounding environment.
1.1 Applications
• Power system monitoring
• PCB thermal monitoring
• HVAC
• Thermocouple cold junction compensation
• Industrial control
• Environmental monitoring
• Cold-chain industry (transport & storage)
1.2 Key features
• Temperature range: -40 to 125 °C
• Output data rate: 25 Hz upto 200 Hz
• Temperature data: 16-bits
• Low current consumption: 1.75 µA in single conversion mode
• Digital interface: I2C
• Interrupt pin functionality: programmable temperature threshold
1.3 Ordering information
WE order code Dimensions Description
2521020222501 2.0 x 2.0 x 0.5 mm Tape & reel packaging
2521020222581 2.0 x 2.0 x 0.5 mm 5 pcs cut tape packaging
2521020222591 33 x 20 x 7 mm Evaluation board temperature sensor IC
Table 1: Ordering information
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 5
2 Sensor specifications
2.1 General information
Parameter Value
Operating temperature -40°C up to 125°C
Storage conditions <40°C; <75% RH
Communication interface I2C
Moisture sensitivity level (MSL) 1
Electrostatic discharge protection (HBM) 2 kV
Table 2: General information
2.2 Absolute maximum ratings
Absolute maximum ratings are the limits; the device can be exposed to without causing
permanent damage. Exposure to absolute maximum conditions for extended periods may
affect device reliability.
Parameter Symbol
Input voltage VDD pin V
Input voltage SDA, SCL & SAO pins V
Table 3: Absolute maximum ratings
Supply voltage on any pin should never exceed 4.8 V.
The device is susceptible to be damaged by electrostatic discharge (ESD).
Always use proper ESD precautions when handling. Improper handling of the
device can cause performance degradation or permanent damage.
DD_MAX
IN_MAX
Value
Unit
Min Max
-0.3 4.8 V
-0.3 VDD+0.3 V
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 6
2.3 Temperature sensor specification
Unless otherwise stated, all specified values were measured under the following conditions:
T=25°C, VDD=3.3 V.
Parameter
Measurement
range
Absolute accuracy
Total accuracy
Resolution
Sensitivity
Output data rate
Noise (RMS)
1
Boot-on time
Symbol
Test conditions
Min Typ Max
Value
T
RANGE
T
ACC_ABS
T
ACC_TOT
RES
SEN
ODR
T= -10 to 60°C -0.5 ±0.25 0.5 °C
T= -40 to 125°C -1.0 ±0.7 1.0 °C
T
T
Continuous
mode
-40 125 °C
25 200 Hz
ODR= 25 Hz 0.025
ODR= 50 Hz 0.035
T
NOISE
ODR= 100 Hz 0.050
ODR= 200 Hz 0.060
t
BOOT
Table 4: Temperature sensor specifications
Unit
16 bit
0.01 °C/digit
°C RMS
12 ms
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 7
2.4 Electrical specifications
Unless otherwise stated, all specified values were measured under the following conditions:
T=25°C, VDD=3.3V.
Parameter
Operating supply voltage
Current consumption in
power down mode
Current consumption in
single conversion mode
Peak current
consumption
Digital input voltage -
high-level
Digital input voltage -
low-level
Digital output voltage -
high-level
Digital output voltage -
low-level
2
Symbol
V
DD
I
DD_PD
I
DD_SC
I
DD_PEAK
V
IH
V
IL
V
OH
V
IL
Test conditions
During
conversion
Value
Min Typ Max
1.5 3.3 3.6
0.6
1.75
120 180
0.7*V
DD
V
DD_IO
-0.2
0.3*V
0.4
DD
Unit
V
µA
µA
µA
V
V
V
V
Table 5: Electrical specifications
1. Temperature noise RMS is measured in a controlled environment.
2. Averaged supply current with one measurement per second
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 8
3 Pinning information
3.1 Pin configuration
Figure 1: Pin specifications (top view)
3.2 Pin description
Pin
No.
1 SCL I2C serial clock Input
2 INT Interrupt Output Do not connect if not used
3 VDD Positive supply voltage Supply
4 SAO
5 GND
6 SDA I2C serial data Input/Output
Name Function I/O Comments
I2C device address
selection
Negative supply
voltage
Table 6: Pin description
Input
Supply
High: device address is 0111000b
Low: device address is 0111111b
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 9
4 Digital interface
Microcontroller
(Master)
R
p
R
p
Sensor
(Slave-1)
Sensor
(Slave-2)
+VDD
SCL
(serial clock)
SDA
(serial data)
Pull up resistors
The sensor supports standard I2C (Inter-IC) bus protocol. Further information about the I2C
interface can be found at https://www.nxp.com/docs/en/user-guide/UM10204.pdf . I2C is a
serial 8-bit protocol with two-wire interface that supports communication between different
ICs, for example, between microcontrollers and other peripheral devices.
4.1 General characteristics
A serial data line (SDA) and a serial clock line (SCL) are required for the communication
between the devices connected via I2C bus. Both SDA and SCL lines are bidirectional. The
output stages of devices connected to the bus must have an open-drain or open-collector.
Hence, the SDA and SCL lines are connected to a positive supply voltage via pull-up resistors. In I2C protocol, the communication is realized through master-slave principle. A master
device generates the clock pulse, a start command and a stop command for the data transfer. Each connected device on the bus is addressable via a unique address. Master and
slave can act as a transmitter or a receiver depending upon whether the data needs to be
sent or received.
This sensor behaves like a slave device on the I2C bus.
Temperature Sensor IC, Part Nr. 2521020222501
Figure 2: Master-slave concept
User manual version 1.0 © February 2020
www.we-online.com/sensors 10
4.2 SDA and SCL logic levels
Voltage
low
high
Time
V
DD
GND
0.2 x V
DD
0.8 x V
DD
The positive supply voltage to which SDA and SCL lines are pulled up (through pull-up
resistors), in turn determines the high level input for the slave devices. The logic high ’1’ and
logic low ’0’ levels for the SDA and SCL lines then depend on the VDD. Input reference levels
for this sensor are set as 0.8 * VDD (for logic high) and 0.2 * VDD (for logic low). Explained
in the figure3.
Figure 3: SDA and SCL logic levels
4.3 Communication phase
4.3.1 Idle state
During the idle state, the bus is free and both SDA and SCL lines are in logic high ’1’ state.
4.3.2 START(S) and STOP(P) condition
Data transfer on the bus starts with a START command, which is generated by the master.
A start condition is defined as a high-to-low transition on the SDA line while the SCL line is
held high. The bus is considered busy after the start condition.
Data transfer on the bus is terminated with a STOP command, which is also generated by
the master. A low-to-high transition on the SDA line, while the SCL line being high is defined
as a STOP condition. After the stop condition, the bus is again considered free and is in idle
state. Figure4shows the I2C bus START and STOP conditions.
Master can also send a REPEATED START (SR) command instead of STOP command.
REPEATED START condition is the same as the START condition.
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 11
4.3.3 Data validity
SDA
SCL
START
Condition
STOP
Condition
Valid
data
Valid change
of data
After the start condition, one data bit is transferred with each clock pulse. The transmitted
data is only valid when the SDA line data is stable (high or low) during the high period of the
clock pulse. High or low state of the data line can only change when clock pulse is in low
state.
Figure 4: Data validity, START and STOP condition
4.3.4 Byte format
Data transmission on the SDA line is always done in bytes, with each byte being 8-bits long.
Data is transferred with the most significant bit (MSB) followed by other bits.
If the slave cannot receive or transmit another complete byte of data, it can force the master
into a wait state by holding SCL low. Data transfer continues when the slave is ready which
is indicated by releasing the SCL line.
4.3.5 Acknowledge(ACK) and No-Acknowledge(NACK)
Each byte sent on the data line must be followed by an Acknowledge bit. The receiver (master or slave) generates an Acknowledge signal to indicate that the data byte was received
successfully and another data byte could be sent.
After one byte is transmitted, the master generates an additional Acknowledge clock pulse
to continue the data transfer. The transmitter releases the SDA line during this clock pulse
so that the receiver can pull the SDA line to low state in such a way that the SDA line
remains stable low during the entire high period of the clock pulse. This is considered as an
Acknowledge signal.
In case the receiver does not want to receive any further byte, it does not pull down the SDA
line and it remains in stable high state during the entire clock pulse. This is considered as
a No-Acknowledge signal and the master can generate either a stop condition to terminate
the data transfer or a repeated start condition to initiate a new data transfer.
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 12
4.3.6 Slave address for the sensor
The slave address is transmitted after the start condition. Each device on the I2C bus has a
unique address. Master selects the slave by sending corresponding address after the start
condition. A slave address is 7 bits long followed by a Read/Write bit.
Depending on the connection of the SAO pin, the 7-bit slave address for this sensor can
either be 0111000b or 0111111b. When SAO is connected to positive supply voltage, the
7-bit slave address is 0111000b (0x38). If SAO is connected to ground, 7-bit slave address
is 0111111b (0x3F).
The R/W bit determines the data direction. A ’0’ indicates a write operation (transmission
from master to slave) and a ’1’ indicates a read operation (data request from slave).
Slave address[6:3]
0111 0 01110000b (0x70)
0111
0111 0 01111110b (0x7E)
0111
Slave address[2:0]
000
7-bit slave address R/W Slave address + R/W
0111000b (0x38)
1 01110001b (0x71)
111
0111111b (0x3F)
1 01111111b (0x7F)
Table 7: Slave address and Read/Write commands
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 13
4.3.7 Read/Write operation
START
Condition
STOP
Condition
1...7 8 9 1.. .8
9
1...8 9
7-bit
Address
Read/
Write
ACK
Register
Address
ACK NACKData
Once the slave-address and data direction bit is sent, the slave acknowledges the master.
The next byte sent by the master must be a register-address of the sensor. This indicates
the address of the register where data needs to be written to or read from.
Figure 5: Complete data transfer
After receiving the register address, the slave sends an Acknowledgement (ACK). If the
master is still writing to the slave (R/W bit = 0), it will transmit the data to slave in the same
direction. If the master wants to read from the addressed register (R/W bit =1), a repeated
start (SR) condition must be sent to the slave. Master acknowledges the slave after receiving
each data byte. If the master no longer wants to receive further data from the slave, it would
send No-Acknowledge (NACK). Afterwards, Master can send a STOP condition to terminate
the data transfer. Figure6shows the writing and reading procedures between the master
and the slave device (sensor).
Temperature Sensor IC, Part Nr. 2521020222501
User manual version 1.0 © February 2020
www.we-online.com/sensors 14
Loading...