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TMP461

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SBOS722B – JUNE 2015 – REVISED AUGUST 2016

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8.6.1.5 Conversion Rate Register

The conversion rate register (read address 04h, write address 0Ah) controls the rate at which temperature

conversions are performed. This register adjusts the idle time between conversions but not the conversion time

itself, thereby allowing the TMP461 power dissipation to be balanced with the temperature register update rate.

Table 7 lists the conversion rate options and corresponding time between conversions. The default value of the

register is 08h, which gives a default rate of 16 conversions per second.

Table 7. Conversion Rate

VALUE

CONVERSIONS PER SECOND

TIME (Seconds)

00h

0.0625

16

01h

0.125

8

02h

0.25

4

03h

0.5

2

04h

1

1

05h

2

0.5

06h

4

0.25

07h

8

0.125

08h

16 (default)

0.0625 (default)

09h

32

0.03125

8.6.1.6 One-Shot Start Register

When the TMP461 device is in shutdown mode (SD = 1 in the configuration register), a single conversion is

started by writing any value to the one-shot start register, pointer address 0Fh. This write operation starts one

conversion and comparison cycle on either both the local and remote sensors or on only one or the other sensor,

depending on the LEN and REN values configured in the channel enable register (read address 16h, write

address 16h). The TMP461 device returns to shutdown mode when the cycle completes. The value of the data

sent in the write command is irrelevant and is not stored by the TMP461 device.

8.6.1.7 Channel Enable Register

The channel enable register (read address 16h, write address 16h) enables or disables the temperature

conversion of remote and local temperature sensors. LEN (bit 0) of the channel enable register enables/disables

the conversion of local temperature. REN (bit 1) of the channel enable register enables/disables the conversion

of remote temperature. Both LEN and REN are set to 1 (default), this enables the ADC to convert both local and

remote temperatures. If LEN is set to 0, the local temperature conversion is disabled and similarly if REN is set

to 0, the remote temperature conversion is disabled.

Both local and remote temperatures are converted by the internal ADC as a default mode. Channel Enable

register can be configured to achieve power savings by reducing the total ADC conversion time to half for

applications that do not require both remote and local temperature information.

8.6.1.8 Consecutive ALERT Register

The Consecutive ALERT register (read address 22h, write address 22h) controls the number of out-of-limit

temperature measurements required for ALERT to be asserted. Table 8 summarizes the values of the

consecutive ALERT register. The number programmed in the consecutive ALERT applies to both the remote and

local temperature results. When the number of times that the temperature result consecutively exceeds the high

limit register value is equal to the value programmed in the consecutive ALERT register, ALERT is asserted.

Similarly, the consecutive ALERT register setting is also applicable to the low-limit register.

Table 8. Consecutive ALERT

REGISTER VALUE

NUMBER OF OUT-OF-LIMIT MEASUREMENTS REQUIRED TO ASSERT ALERT

01h

1 (default)

03h

2

07h

3

0Fh

4