SBAS994B September 2023 – September 2023 AMC131M03
PRODUCTION DATA
The AMC131M03 offers an integrated temperature sensor that is multiplexed with the AIN2P input of the voltage channel. The TS_EN bit in the CH2_CFG register selects the temperature sensor mode for the ADC channel connected to the AIN2P input of the AMC131M03. If the TS_EN bit is 0b the ADC measures the voltage between the AIN2P and AIN12N pins (channel 2 input). If the TS_EN bit is 1b, the ADC for this channel is in temperature sensor measurement mode.
Do not use the temperature sensor measurement mode and the global-chop mode at the same time on the AMC131M03. When the TS_EN bit in the CH2_CFG register is set to 1b, the GC_EN bit in the GLOBAL_CHOP_CFG register must be set to 0b.
There are two options for the temperature sensor measurement: internal and external temperature sensor mode. Use the TS_SEL bit in the CH2_CFG register to configure the internal or external temperature measurement mode. If the TS_SEL bit in the CH2_CFG register is set to 0b, the internal temperature sensor mode is selected. In this mode, the ADC on channel 2 measures the internal temperature sensor. Set the TS_SEL bit in the CH2_CFG register to 1b to select the external temperature sensor mode. In external temperature sensor mode, the ADC on channel 2 measures the voltage between the AIN2P and AIN12N pins for sensing an external temperature sensor, such as a positive (PTC) or negative temperature coefficient (NTC) element. This mode is very similar to the generic ADC measurement of a voltage between the AIN2P and AIN12N pins (channel 2 input); however, the conversion rate is reduced as explained in this section, with the benefit of increasing the input impedance.
Temperature readings follow the same process as the analog inputs for starting and reading conversion results; however, the conversion rate for temperature measurements is reduced by a factor of 32 in comparison to the other ADC channels. The benefit is a significantly increased input impedance. New temperature readings are available at channel 2 at every 32nd falling edge of DRDY, and new conversion results at channel 0 and channel 1 are available at every falling edge of DRDY. The DRDY2 bit in the STATUS register is set to high when a new temperature reading is available.