TMP9R01DGSSLASHEM datasheet(32/45 Pages) TI2

32 / 45 page

NPN transistors must be diode-connected. PNP transistors can either be transistor- or diode-connected (see

Figure 7-1). The D+ pin waveform is shown in Figure 9-2 while a transistor is connected between the D+ and

D– pins. Due to three different source currents shown in Figure 7-2, the D+ waveform has 3 levels of voltages

during temperature conversion.

Time (s)

0.01

0.02

0.03

0.04

0.05

-0.2

0.2

0.4

0.6

0.8

Time (s)

0.02

0.0208

0.0216

0.0224

0.0232

0.024

0.5

0.55

0.6

0.65

0.7

Temperature

Conversion

Figure 9-2. D+ Waveform

Errors in remote temperature sensor readings are typically the consequence of the ideality factor and current

excitation used by the device versus the manufacturer-specified operating current for a given transistor. Some

manufacturers specify a high-level and low-level current for the temperature-sensing substrate transistors. The

device uses 7.5μA for ILOW and 120μA for IHIGH.

The ideality factor (η) is a measured characteristic of a remote temperature sensor diode as compared to an

ideal diode. The TMP9R01-SEP and TMP9R01-SP devices allow for different η-factor values; see the η-Factor

Correction Register section.

The ideality factor for the TMP9R01-SEP and TMP9R01-SP devices is trimmed to be 1.008. For transistors that

have an ideality factor that does not match the device, Equation 4 can be used to calculate the temperature

error.

Note

For Equation 4 to be used correctly, the actual temperature (°C) must be converted to Kelvin (K).

TERR= η−1.008

1.008 ×(273.15+T(∘C))

(4)

where

• TERR = error in the TMP9R01-SEP and TMP9R01-SP devices because η ≠ 1.008,

• η = ideality factor of the remote temperature sensor,

• T(°C) = actual temperature, and

In Equation 4, the degree of delta is the same for °C and K.

For η = 1.004 and T(°C) = 100°C:

TMP9R01-SEP, TMP9R01-SP

SNIS238A – JULY 2025 – REVISED JULY 2026

www.ti.com

Submit Document Feedback

Product Folder Links: TMP9R01-SEP TMP9R01-SP

TMP9R01DGS/EM Datasheet(PDF) 32 Page - Texas Instruments

TMP9R01DGS/EM Datasheet(HTML) 32 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45

Datasheet Download

Link URL