Si7013
I
2
C H
UMIDITY
Features
AND
T
W O
- Z
ONE
T
EMPERATURE
S
ENSOR
Precision Relative Humidity Sensor
± 3% RH (max), 0–80% RH
High Accuracy Temperature Sensor
±0.4 °C (max), –10 to 85 °C
0 to 100% RH operating range
Up to –40 to +125 °C operating
range
Low Voltage Operation (1.9 to 3.6 V)
Low Power Consumption
150 µA active current
60 nA standby current
Factory-calibrated
I
2
C Interface
Integrated on-chip heater
Auxiliary Sensor input
Direct readout of remote
thermistor temperature in °C
Package: 3x3 mm DFN
Excellent long term stability
Optional factory-installed cover
Low-profile
Protection during reflow
Excludes liquids and particulates
Si7013
Ordering Information:
See page 35.
Applications
HVAC/R
Thermostats/humidistats
Instrumentation
White goods
Micro-environments/data centers
Industrial Controls
Indoor weather stations
Pin Assignments
Description
The Si7013 I
2
C Humidity and 2-Zone Temperature Sensor is a monolithic CMOS
IC integrating humidity and temperature sensor elements, an analog-to-digital
converter, signal processing, calibration data, and an I
2
C Interface. The patented
use of industry-standard, low-K polymeric dielectrics for sensing humidity enables
the construction of low-power, monolithic CMOS Sensor ICs with low drift and
hysteresis, and excellent long term stability.
The humidity and temperature sensors are factory-calibrated and the calibration
data is stored in the on-chip non-volatile memory. This ensures that the sensors
are fully interchangeable, with no recalibration or software changes required.
An auxiliary sensor input with power management can be tied directly to an
external thermistor network or other voltage-output sensor. On-board logic
performs calibration/linearization of the external input using user-programmable
coefficients. The least-significant bit of the Si7013's I
2
C address is programmable,
allowing two devices to share the same bus.
The Si7013 is available in a 3x3 mm DFN package and is reflow solderable. The
optional factory-installed cover offers a low profile, convenient means of protecting
the sensor during assembly (e.g., reflow soldering) and throughout the life of the
product, excluding liquids (hydrophobic/oleophobic) and particulates.
The Si7013 offers an accurate, low-power, factory-calibrated digital solution ideal
for measuring humidity, dew-point, and temperature, in applications ranging from
HVAC/R and asset tracking to industrial and consumer platforms.
SDA
AD0/VOUT
GNDD
GNDA
VSNS
1
2
3
4
5
Top View
10
SCL
9 VDDD
8 VDDA
7
6
VINN
VINP
Patent Protected. Patents pending
Rev. 0.95 11/13
Copyright © 2013 by Silicon Laboratories
Si7013
This information applies to a product under development. Its characteristics and specifications are subject to change without notice.
Si7013
Functional Block Diagram
VSNS
Vdd
Si7013
Humidity
Sensor
1.25V
Ref
Calibration
Memory
AD0/VOUT
Temp
Sensor
ADC
Control Logic
VINP
VINN
Analog
Input
I
2
C Interface
SDA
SCL
GND
2
Rev. 0.95
Si7013
T
ABLE
Section
OF
C
ONTENTS
Page
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2. Typical Application Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3. Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.1. Relative Humidity Sensor Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.2. Hysteresis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.3. Prolonged Exposure to High Humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
4.4. PCB Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.5. Protecting the Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.6. Bake/Hydrate Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.7. Long Term Drift/Aging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
5. I2C Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.1. Issuing a Measurement Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
5.2. Reading and Writing User Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.3. Measuring Analog Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.4. Nonlinear Correction of Voltage Inputs: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.5. Firmware Revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5.6. Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5.7. Electronic Serial Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
6. Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
6.1. Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
7. Pin Descriptions: Si7013 (Top View) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
8. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
9. Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
9.1. Package Outline: 3x3 10-pin DFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
9.2. Package Outline: 3x3 10-pin DFN with Protective Cover . . . . . . . . . . . . . . . . . . . . . 38
10. PCB Land Pattern and Solder Mask Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
11. Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
11.1. Si7013 Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
11.2. Top Marking Explanation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
12. Additional Reference Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Document Change List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Rev. 0.95
3
Si7013
1. Electrical Specifications
Unless otherwise specified, all min/max specifications apply over the recommended operating conditions.
Table 1. Recommended Operating Conditions
Parameter
Power Supply
Operating Temperature
Operating Temperature
Symbol
V
DD
T
A
T
A
I and Y grade
G grade
Test Condition
Min
1.9
–40
–40
Typ
—
—
—
Max
3.6
+125
+85
Unit
V
°C
°C
Table 2. General Specifications
1.9 < V
DD
< 3.6 V; T
A
= –40 to 85 °C (G grade) or –40 to 125 °C (I/Y grade); default conversion time unless otherwise noted.
Parameter
Input Voltage High
Input Voltage Low
Input Voltage Range
Input Leakage
Symbol
V
IH
V
IL
V
IN
I
IL
Test Condition
AD0, SCL, SDA, VSNS pins
AD0, SCL, SDA, VSNS pins
SCL, SDA, RSTb pins with respect to
GND
SCL, SDA pins; V
IN
= GND
VSNS pin (200K nominal pull up);
Vin = GND
Min
0.7xV
DD
—
0.0
—
Typ
—
—
—
—
5xV
DD
Max
—
0.3xV
DD
V
DD
1
Unit
V
V
V
μA
μA
Output Voltage Low
V
OL
SDA pin; I
OL
= 2.5 mA; V
DD
= 3.3 V
SDA pin; I
OL
= 1.2 mA;
V
DD
= 1.9 V
—
—
—
—
—
—
—
150
90
0.06
0.06
3.5
3.5
3.1 to 94.2
0.6
0.4
—
—
—
180
120
0.62
3.8
4.0
4.0
—
V
V
V
V
V
μA
μA
μA
μA
mA
mA
mA
Output Voltage High
V
OH
VOUT pin, I
OH
= –0.5 mA, V
DD
= 2.0 V V
DD
– 0.2
VOUT pin, I
OH
= –10
μA
V
DD
– 0.1
VOUT pin, I
OH
= –1.7 mA, V
DD
= 3.0 V V
DD
– 0.4
RH conversion in progress
—
Temperature conversion in progress
Standby, –40 to +85 °C
2
Standby, –40 to +125 °C
2
Peak IDD during powerup
3
Peak IDD during I
2
C operations
4
—
—
—
—
—
—
Current Consump-
tion
I
DD
Heater Current
5
I
HEAT
Notes:
1.
Initiating a RH measurement will also automatically initiate a temperature measurement. The total conversion time will
be t
CONV
(RH) + t
CONV
(T).
2.
No conversion or I
2
C transaction in progress. Typical values measured at 25 °C.
3.
Occurs once during powerup. Duration is <5 msec.
4.
Occurs during I
2
C commands for Reset, Read/Write User Registers, Read EID, Read Firmware Version, Read/Write
Thermistor Coefficients and Read Thermistor. Duration is <50
μs
for all commands except Read Thermistor, which has
<150
μs
duration.
5.
Additional current consumption when HTRE bit enabled. See Section “5.6. Heater” for more information.
4
Rev. 0.95
Si7013
Table 2. General Specifications (Continued)
1.9 < V
DD
< 3.6 V; T
A
= –40 to 85 °C (G grade) or –40 to 125 °C (I/Y grade); default conversion time unless otherwise noted.
Parameter
Conversion Time
1
Symbol
t
CONV
Test Condition
RH or Voltage Normal
RH or Voltage Fast
Temp Normal
Temp Fast
Min
—
—
—
—
—
—
Typ
5.8
2.6
4
1.5
18
—
Max
7
3.1
4.8
1.8
25
80
Unit
ms
ms
ms
ms
ms
ms
Powerup Time
t
PU
From V
DD
≥
1.9 V to ready for a
conversion, 25 °C
From VDD
≥
1.9 V to ready for a
conversion, full temperature range
Notes:
1.
Initiating a RH measurement will also automatically initiate a temperature measurement. The total conversion time will
be t
CONV
(RH) + t
CONV
(T).
2.
No conversion or I
2
C transaction in progress. Typical values measured at 25 °C.
3.
Occurs once during powerup. Duration is <5 msec.
4.
Occurs during I
2
C commands for Reset, Read/Write User Registers, Read EID, Read Firmware Version, Read/Write
Thermistor Coefficients and Read Thermistor. Duration is <50
μs
for all commands except Read Thermistor, which has
<150
μs
duration.
5.
Additional current consumption when HTRE bit enabled. See Section “5.6. Heater” for more information.
Table 3. I
2
C Interface Specifications
1
1.9
V
DD
3.6 V; T
A
= –40 to +85 °C (G grade) or –40 to +125 °C (I/Y grade) unless otherwise noted.
Parameter
Hysteresis
SCLK Frequency
2
SCL High Time
SCL Low Time
Start Hold Time
Start Setup Time
Stop Setup Time
Bus Free Time
SDA Setup Time
SDA Hold Time
Symbol
V
HYS
f
SCL
t
SKH
t
SKL
t
STH
t
STS
t
SPS
t
BUF
t
DS
t
DH
Test Condition
High-to-low versus low-to-
high transition
Min
0.05 x V
DD
—
0.6
1.3
0.6
0.6
0.6
Typ
—
—
—
—
—
—
—
—
—
—
Max
—
400
—
—
—
—
—
—
—
—
Unit
V
kHz
µs
µs
µs
µs
µs
µs
ns
ns
Between Stop and Start
1.3
100
100
Notes:
1.
All values are referenced to V
IL
and/or V
IH
.
2.
Depending on the conversion command, the Si7013 may hold the master during the conversion (clock stretch). At
above 300 kHz SCL, the Si7013 may hold the master briefly for user register and device ID transactions. At the highest
I
2
C speed of 400 kHz the stretching will be <10 µs.
3.
Pulses up to and including 50ns will be suppressed.
Rev. 0.95
5