7 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, as well as validating and testing their design

implementation to confirm system functionality.

7.1 Application Information

The ISOTMP35R device offers versatile features designed for a wide range of high-voltage temperature-sensing

applications. The ISOTMP35R operates from a supply voltage as low as 3V with a typical current consumption

of only 45μA. This low-power capability makes the ISOTMP35R device well suited for battery-powered systems,

including applications where multiple cells are stacked to generate high output voltages.

7.1.1 External Buffer

In case of higher capacitance on the output or a long trace between the sensor and the ADC, an external buffer

can be added. This implementation is shown in Figure 7-1 for the signal to be a temperature voltage to be sent

through a differential pair.

+

25

25

THP210

ISOTMP35R

V

OUT

GND

GND

50

Figure 7-1. Buffered Differential Pair Data Transmission

7.1.2 ADC Interface Considerations

The ISOTMP35R device provides an analog voltage output (VOUT) that can be digitized using an external

analog-to-digital converter (ADC). To ensure accurate temperature measurements, TI recommends using an

ADC with at least 12-bit resolution. With a 2.5V reference, a 12-bit ADC provides an LSB of approximately

0.61mV, corresponding to a temperature resolution of 0.061°C per LSB. This resolution is sufficient for most

applications requiring precise temperature monitoring.

When interfacing the ISOTMP35R device with an ADC, additional circuitry is recommended to ensure signal

integrity:

• CLOAD capacitor: Stabilizes VOUT and reduces ripples caused by high-voltage transients across the isolation

barrier, and should be placed close to the ISOTMP35R VOUT pin.

• RC filter (RFILTER, CFILTER): Suppresses noise on the VOUT line and should be placed close to the ADC input.

• CFILTER capacitor: Also acts as a charge reservoir to mitigate voltage glitches during ADC sampling.

Figure 7-2 illustrates a recommended circuit for connecting the ISOTMP35R output to an ADC. This

configuration ensures accurate digitization of the ISOTMP35R output with minimal noise and transient effects.

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ISOTMP35R

SNIS244 – SEPTEMBER 2025

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