Datasheet

Table Of Contents
4.10.3.6. Interrupts
An interrupt can be generated when the FIFO level reaches a configurable threshold FCS.THRESH. The interrupt output
must be enabled via INTE.
Status can be read from INTS. The interrupt is cleared by draining the FIFO to a level lower than FCS.THRESH.
4.10.3.7. Supply
The ADC supply is separated out on its own pin to allow noise filtering.
4.10.4. Temperature Sensor
The temperature sensor measures the Vbe voltage of a biased bipolar diode, connected to the fifth ADC channel
(AINSEL=4). Typically, Vbe = 0.706V at 27 degrees C, with a slope of -1.721mV per degree. Therefore the temperature can
be approximated as follows:
T = 27 - (ADC_voltage - 0.706)/0.001721
As the Vbe and the Vbe slope can vary over the temperature range, and from device to device, some user calibration may
be required if accurate measurements are required.
The temperature sensor’s bias source must be enabled before use, via CS.TS_EN. This increases current consumption on
ADC_IOVDD by approximately 40 μA.
4.10.5. List of Registers
Table 593. List of ADC
registers
Offset Name Info
0x00 CS ADC Control and Status
0x04 RESULT Result of most recent ADC conversion
0x08 FCS FIFO control and status
0x0c FIFO Conversion result FIFO
0x10 DIV Clock divider. If non-zero, CS_START_MANY will start conversions
at regular intervals rather than back-to-back.
The divider is reset when either of these fields are written.
Total period is 1 + INT + FRAC / 256
0x14 INTR Raw Interrupts
0x18 INTE Interrupt Enable
0x1c INTF Interrupt Force
0x20 INTS Interrupt status after masking & forcing
CS Register
Description
ADC Control and Status
Table 594. CS Register
Bits Name Description Type Reset
31:21 Reserved. - - -
RP2040 Datasheet
4.10. ADC and Temperature Sensor 586