TMP117 datasheet(14/50 Pages) TI2

14 / 50 page

7.4 Device Functional Modes

The TMP117 can be configured to operate in various conversion modes by using the MOD[1:0] bits. These

modes provide flexibility to operate the device in the most power efficient way necessary for the intended

application.

7.4.1 Continuous Conversion Mode

When the MOD[1:0] bits are set to 00 or 10 in the configuration register, the device operates in continuous

conversion mode. The device continuously performs temperature conversions in this mode, as shown in Figure

7-3, and updates the temperature result register at the end of every active conversion. The user can read the

configuration register or the temperature result register to clear the Data_Ready flag. Therefore, the Data_Ready

flag can be used to determine when the conversion completes so that an external controller can synchronize

reading the result register with conversion result updates. The user can set the DR/nAlert_EN bit in the

configuration register to monitor the state of the Data_Ready flag on the ALERT pin.

Every conversion cycle consists of an active conversion period followed by a standby period. The device

typically consumes 135 µA during active conversion and only 1.25 µA during the low-power standby period.

Figure 7-3 shows a current consumption profile of a conversion cycle while in continuous current mode. The

duration of the active conversion period and standby period can be configured using the CONV[2:0] and

AVG[1:0] bits in the configuration register, thereby allowing the average current consumption of the device to

be optimized based on the application requirements. Changing the conversion cycle period also affects the

temperature result update rate because the temperature result register is updated at the end of every active

conversion.

Use Equation 1 to calculate the average current consumption of the device in continuous conversion mode.

(Active Current Consumption Active Conversion Time) + (Standby Current Consumption Standby Time)

Conversion Cycle Time

(1)

Active conversion time

Conversion Cycle time Conversion Cycle time

tStandby timet

Start of conversion

(Affected by averaging)

Figure 7-3. Conversion Cycle Timing Diagram

7.4.2 Shutdown Mode (SD)

When the MOD[1:0] bits are set to 01 in the configuration register, the device instantly aborts the currently

running conversion and enters a low-power shutdown mode. In this mode, the device powers down all active

circuitry and can be used in conjunction with the OS mode to perform temperature conversions. Engineers

can use the TMP117 for battery-operated systems and other low-power consumption applications because the

device typically only consumes 250 nA in SD mode.

TMP117

SNOSD82D – JUNE 2018 – REVISED SEPTEMBER 2022

www.ti.com

Submit Document Feedback

Product Folder Links: TMP117

TMP117 Datasheet(PDF) 14 Page - Texas Instruments