Si 7 0 1 5 - A2 0
D
IGITA L
I
2
C H
UMIDITY AND
T
EMPERATURE
S
ENSOR
Features
Precision Relative Humidity Sensor
±
4.5% RH (max), 0–80% RH
ºC (max), –10 to 85 °C
Drop-In Upgrade for Si7005
Factory-calibrated
High-Accuracy Temperature Sensor
±1
0 to 100% RH operating range
0 to +70 °C operating range (FM)
–40 to +85 °C operating range (GM)
Low Voltage Operation (1.9 to 3.6 V)
Low Power Consumption
150
I
2
C Interface
Integrated on-chip heater
4x4 mm QFN package
Excellent long term stability
Optional factory-installed
cover
Low-profile
Protection
µA active current
60 nA standby current
Ordering Information
See page 31.
Patent protected; patents pending
Pin Assignments
GND
19
18 DNC
17 DNC
16 DNC
15 CS
14 DNC
13 DNC
10
11
GND
12
DNC
7
8
9
DNC
DNC
DNC
DNC
21
DNC
DNC
20
during reflow
Excludes liquids and
particulates
Applications
HVAC/R
Thermostats/humidistats
Instrumentation
White goods
Micro-environments/data centers
Industrial controls
Weather stations
Asset tracking and storage
GND
1
2
3
4
5
6
DNC
SCL
SDA
DNC
DNC
24
23
GND
Description
The Si7015 I
2
C Humidity and 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.
Each unit is 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. The
Si7015 can be used as a drop-in upgrade for the Si7005 with only minor
software changes because the register sets are the same, and the
4x4 mm QFN package is footprint-compatible with that of the Si7005.
The device is compatible with standard SMT assembly processes, such
as reflow. The optional factory-installed cover offers a low profile and
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 Si7015 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.
Rev. 1.2 8/16
Copyright © 2016 by Silicon Laboratories
DNC
V
DD
22
Si7015-A20
Si7015-A20
Functional Block Diagram
2
Rev. 1.2
Si7015-A20
T
ABLE O F
C
ONTENTS
Section
Page
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2. Typical Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
3. Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.2. Relative Humidity Sensor Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.3. Temperature Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.4. Hysteresis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.5. Prolonged Exposure to High Humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.6. PCB Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.7. Protecting the Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.8. Bake/Hydrate Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.9. Long Term Drift/Aging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5. Host Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
5.1. I2C Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
5.2. I2C Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
6. Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
6.1. Register Detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
7. Pin Descriptions: Si7015 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
8. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
9. Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
9.1. 24-Pin QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
9.2. 24-Pin QFN with Protective Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
10. PCB Land Pattern and Solder Mask Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
11. Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
11.1. Si7015 Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
11.2. Top Marking Explanation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
12. Additional Reference Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Rev. 1.2
3
Si7015-A20
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
F grade
G grade
Test Condition
Min
1.9
0
–40
Typ
—
—
—
Max
3.6
+70
+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 0 to 70 °C (F 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
1
AD0, SCL, SDA pins
AD0, SCL, SDA pins
SCL, SDA, RSTb pins with respect to
GND
SCL, SDA pins; V
IN
= GND
CS 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
24
0.6
0.4
180
120
—
V
V
µA
µA
mA
Current
Consumption
I
DD
RH conversion in progress
Temperature conversion in progress
CS < V
IL
; no conversion in progress;
V
DD
= 3.3 V;
SDA = SCL
≥
V
IH
; HEAT = 1
Standby
2
, –40 to +85°C
Peak I
DD
during powerup
3
Peak I
DD
during I
2
C operations
4
—
—
—
—
—
—
—
0.06
3.5
3.5
5.8
2.6
4.0
1.5
0.62
4.0
4.0
7.0
3.1
6.2
2.4
µA
mA
mA
ms
ms
ms
ms
Conversion Time
t
CONV
RH Normal (Fast = 0)
RH Fast (Fast = 1)
Temperature Normal (Fast = 0)
Temperature Fast (Fast = 1)
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 Read Device ID and Read Firmware Version. Duration is < 100 µs when I
2
C clock
speed is >100 kHz.
4
Rev. 1.2
Si7015-A20
Table 2. General Specifications (Continued)
1.9 < V
DD
< 3.6 V; T
A
= –40 to 85 °C (G grade) or 0 to 70 °C (F grade); default conversion time unless otherwise noted.
Parameter
Wake Up Time
Power Up Time
Symbol
t
CS
t
PU
Test Condition
1
From CS < VIL to ready for a temp/RH
conversion
From V
DD
≥
1.9 V to ready for a temp/
RH conversion, 25°C
From V
DD
≥
1.9 V to ready for a temp/
RH conversion, full temperature range
Min
—
—
—
Typ
—
18
—
Max
1
25
80
Unit
ms
ms
ms
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 Read Device ID and Read Firmware Version. Duration is < 100 µs when I
2
C clock
speed is >100 kHz.
Table 3. I
2
C Interface Specifications
1
1.9 V
DD
3.6 V; T
A
= 0 to 70 °C (F grade) or –40 to +85 °C (G grade) unless otherwise noted.
Parameter
Hysteresis
SCLK Frequency
SCL High Time
SCL Low Time
Start Hold Time
Start Setup Time
Stop Setup Time
Bus Free Time
SDA Setup Time
SDA Hold Time
SDA Valid Time
SDA Acknowledge Valid Time
Suppressed Pulse Width
2
Symbol
V
HYS
f
SCL
t
SKH
t
SKL
t
STH
t
STS
t
SPS
t
BUF
t
DS
t
DH
t
VD;DAT
t
VD;ACK
t
SP
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
—
—
—
—
—
—
—
—
0.9
0.9
—
Unit
V
kHz
µs
µs
µs
µs
µs
µs
ns
ns
µs
µs
ns
Between Stop and Start
1.3
100
100
From SCL low to data valid
From SCL low to data valid
—
—
50
Notes:
1.
All values are referenced to V
IL
and/or V
IH
.
2.
Pulses up to and including 50ns will be suppressed.
Rev. 1.2
5