SCL

GND

ALERT

2

4

1

V+

ADD0

6

3

5

0.01 PF

Two-Wire

Host Controller

TMP101

2.7 V to 5.5 V

SDA

Pull-Up Resistors

Supply Bypass

Capacitor

Supply Voltage

5-k

SCL

GND

ADD1

2

4

1

V+

ADD0

6

3

5

0.01 PF

Two-Wire

Host Controller

TMP100

SDA

Pull-Up Resistors

Supply Bypass

Capacitor

Supply Voltage

5-k

2.7 V to 5.5 V

TMP100, TMP101

www.ti.com

SBOS231I – JANUARY 2002 – REVISED NOVEMBER 2015

8 Application and Implementation

NOTE

Information in the following applications sections is not part of the TI component

specification, and TI does not warrant its accuracy or completeness. TI’s customers are

responsible for determining suitability of components for their purposes. Customers should

validate and test their design implementation to confirm system functionality.

8.1 Application Information

The TMP100 and TMP101 devices are used to measure the printed circuit board (PCB) temperature of the board

location where the devices are mounted. The TMP100 features two address pins to allow up to eight devices to

allowing up to three devices to be connected per bus. The TMP100 and TMP101 devices require no external

components for operation except for pullup resistors on SCL, SDA, and ALERT (TMP101 device), although a

0.1-

μF bypass capacitor is recommended.

The sensing device of the TMP100 and TMP101 devices is the chip itself. Thermal paths run through the

package leads as well as the plastic package. The die flag of the lead frame is connected to GND. The lower

thermal resistance of metal causes the leads to provide the primary thermal path. The GND pin of the TMP100 or

TMP101 device is directly connected to the metal lead frame, and is the best choice for thermal input.

8.2 Typical Application

Figure 12. Typical Connections of the TMP100

Figure 13. Typical Connections of the TMP101

8.2.1 Design Requirements

The TMP100 and TMP101 devices require pullup resistors on the SCL, SDA, and ALERT (TMP101 device) pins.

The recommended value for the pullup resistor is 5-k

Ω. In some applications, the pullup resistor can be lower or

higher than 5-k

Ω but must not exceed 3 mA of current on the SCL and SDA pins, and must not exceed 4 mA on

the ALERT (TMP101) pin. A 0.1-

μF bypass capacitor is recommended, as shown in Figure 12 and Figure 13.

pullup resistors. For the TMP100, to configure one of eight different addresses on the bus, connect ADD0 and

ADD1 to either the GND pin, V+ pin, or float. Float indicates the pin is left unconnected. For the TMP101 device,

to configure one of three different addresses on the bus, connect ADD0 to either the GND pin, V+ pin, or float.

8.2.2 Detailed Design Procedure

Place the TMP100 and TMP101 devices in close proximity to the heat source that must be monitored, with a

proper layout for good thermal coupling. This placement ensures that temperature changes are captured within

the shortest possible time interval. To maintain accuracy in applications that require air or surface temperature

measurement, care must be taken to isolate the package and leads from ambient air temperature. A thermally-

conductive adhesive is helpful in achieving accurate surface temperature measurement.

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Product Folder Links: TMP100 TMP101