Datasheet

I/O
Control
Interface
SCL
SDA
Temperature
Register
Configuration
Register
T
LOW
Register
T
HIGH
Register
Pointer
Register
Device
0.01mF
V+
GND
2
5
3
ALERT
(Output)
4
ADD0
1
SCL
6
SDA
To
Two-Wire
Controller
NOTE:SCL,SDA,andALERT
pinsrequirepull-upresistors.
TMP102
www.ti.com SBOS397C –AUGUST 2007–REVISED OCTOBER 2012
APPLICATION INFORMATION
POINTER REGISTER
The TMP102 is a digital temperature sensor that is
optimal for thermal-management and thermal- Figure 8 shows the internal register structure of the
protection applications. The TMP102 is two-wire- and TMP102. The 8-bit Pointer Register of the device is
SMBus interface-compatible, and is specified over a used to address a given data register. The Pointer
temperature range of –40°C to +125°C. Register uses the two LSBs (see Table 11) to identify
which of the data registers should respond to a read
Pull-up resistors are required on SCL, SDA, and
or write command. Table 1 identifies the bits of the
ALERT. A 0.01μF bypass capacitor is recommended,
Pointer Register byte. During a write command, P2
as shown in Figure 7.
through P7 must always be '0'. Table 2 describes the
pointer address of the registers available in the
TMP102. Power-up reset value of P1/P0 is '00'. By
default, the TMP102 reads the temperature on power-
up.
Figure 7. Typical Connections
The temperature sensor in the TMP102 is the chip
itself. Thermal paths run through the package leads,
as well as the plastic package. The lower thermal
resistance of metal causes the leads to provide the
primary thermal path.
To maintain accuracy in applications requiring air or
Figure 8. Internal Register Structure
surface temperature measurement, care should be
taken to isolate the package and leads from ambient
air temperature. A thermally-conductive adhesive is
Table 1. Pointer Register Byte
helpful in achieving accurate surface temperature
P7 P6 P5 P4 P3 P2 P1 P0
measurement.
0 0 0 0 0 0 Register Bits
Table 2. Pointer Addresses
P1 P0 REGISTER
0 0 Temperature Register (Read Only)
0 1 Configuration Register (Read/Write)
1 0 T
LOW
Register (Read/Write)
1 1 T
HIGH
Register (Read/Write)
Copyright © 2007–2012, Texas Instruments Incorporated Submit Documentation Feedback 5
Product Folder Links: TMP102