SLAAE59 may   2023 AFE539A4

 

  1.   Design Goals
  2.   Design Description
  3.   Design Notes
  4.   Testing Results
    1.     Measured Design Characteristics
  5.   Register Settings
  6.   Pseudo Code Example
  7.   Design Featured Devices
  8.   Design References

Register Settings

General Register Settings
Register
Address		 Register
Name		 Value Description
0x27 STATE-MACHINE-CONFIG0 0x0003 [15:3] 0x0 Don’t care
[2] 0b0: Do not abort state machine
[1] 0b1: Start state machine. Must be enabled in bit 0 as well
[0] 0b1: Enable state machine. Note: State machine must be disabled when configuring registers; enable state machine before saving to NVM.
0x1F COMMON-CONFIG 0x1249 [15] 0b0: Write 0b1 to set window-comparator output to a latching output
[14] 0b0: Write 0b1 to lock device. Unlock by writing 0b0101 to DEVUNLOCK field in the COMMON-TRIGGER register
[13] 0b0: Write 0b1 to set fault-dump read enable at address 0x01
[12] 0b0: Write 0b1 to enable the internal reference
[11:10] 0b11: Power down VOUT3
[9] 0b1: Power down IOUT3
[8:7] 0b11: Power down VOUT2
[6] 0b1: Power down IOUT2
[5:4] 0b11: Powers-down VOUT1
[3] 0b1: Power down IOUT1
[2:1] 0b11: Power down VOUT0
[0] 0b0: Power up IOUT0
0x02 COMMON-TRIGGER 0x0002 [15:12] 0b000: Write 0b0101 to unlock the device
[11:8] 0b0000: Write 0b1010 to trigger a POR reset
[7] 0b0: Write 0b1 to trigger LAFE operation if the respective SYNCCONFIG-X bit in the AFE-X-FUNC-CONFIG register is 1
[6] 0b0: Write 0b1 to set the AFE registers and outputs to zero-code or mid-code based on the respective CLR-SEL-X bit in the AFE-XFUNC-CONFIG register
[5] 0b0: Don’t care
[4] 0b0: Write 0b1 to trigger fault-dump sequence
[3] 0b0: Write 0b1 to trigger PROTECT function
[2] 0b0: Write 0b1 to read one row of NVM for fault-dump
[1] 0b1: Write 0b1 to store applicable register settings to the NVM
[0] 0b0: Write 0b1 to reload applicable registers with existing NVM settings
AFE Output Configuration
Register
Address		 Register
Name		 Value Description
0x03 DAC-0-VOUT-CMP-CONFIG 0x1405 [15:13] 0x0: Don’t care
[12:10] 0b101: Set gain to 4 ×, use internal reference
[9:5] 0x0: Don’t care
[4] 0b0: Set OUTx pin to push-pull
[3] 0b0: Generate comparator output but consume internally
[2] 0b1: FB pin input has finite impedance
[1] 0b0: Do not invert the comparator output
[0] 0b1: Enable comparator mode. Current-output must be in power down
0x09 DAC-1-VOUT-CMP-CONFIG, 0x800 [15:13] 0x0: Don’t care
[12:10] 0b010: Set gain to 1.5 ×, use internal reference
[9:5] Don’t care
[4] 0b0: Set OUTx pin to push-pull
[3] 0b0: Generate comparator output but consume internally
[2] 0b0: FB pin has high impedance
[1] 0b0: Do not invert the comparator output
[0] 0b0: Disable comparator mode.
0x0F DAC-2-VOUT-CMP-CONFIG 0x0403 [15:13] Don’t care
[12:10] 0b001: Set gain to 1 ×, use VDD as reference

[9:5] 0x0: Don’t care
[4] 0b0: Set OUTx pin to push-pull
[3] 0b0: Generate comparator output but consume internally
[2] 0b0: FB pin has high impedance
[1] Invert comparator output
[0] 0b1: Enable comparator mode. Current-output must be in power down
0x15 DAC-3-VOUT-CMP-CONFIG 0x1405 [15:13] 0x0: Don’t care
[12:10] 0b101: Set gain to 4 ×, use internal reference
[9:5] Don’t care
[4] 0b0: Set OUTx pin to push-pull
[3] 0b0: Generate comparator output but consume internally
[2] 0b1: FB pin has finite impedance
[1] 0b0: Do not invert comparator output
[0] 0b1: Enable comparator mode. Current-output must be in power down
SRAM Configuration
Register
Address		 Register
Name		 Value Description
0x20 SRAM_DATA_32 0xE1C0 [15:6] 0b1110000111: Input the maximum voltage output for the AFE. Value provided is for 1.6 V
[5:0] 0x0: Don’t care
0x21 SRAM_DATA_33 0x70C0 [15:6] 0b:0111000011: Configure the minimum output of the AFE
[5:0] 0x0: Don’t care
0x22 SRAM_DATA_34 0x02DA [15:10] 0x0: Don’t care
[9:0] 0b:001011011010: Configure the setpoint value. Setpoint is the value the ADC is compared to by the PI controller
0x23 SRAM_DATA_35 0x007F [15:0] 0b:0000000001111111 Configure the proportional gain (KP) value for the PI controller
0x24 SRAM_DATA_36 0x8000 [15:6] 0b1000000000000000: Set the threshold value of comparator channel 2
[5:0] 0x0: Don’t care
0x25 SRAM_DATA_37 0x2FF [15:12] 0x0: Don’t care
[11:2] 0b0010111111: Configure the common-mode value. The common-mode value is present at the PI output when KP and KI are zero
[1:0] 0x0: Don’t care
0x26 SRAM_DATA_38 0x0007 [15:0] 0b0000000000000011: Select the integral gain value for the PI Controller. Setting this value to 0 disables KI
0x27 SRAM_DATA_39 0x0002 [15:6] 0b0000000000: Safe-Output value
[5:2] 0x0: Don’t care
[1] 0b1: Select a finite-impedance input for ADC0
[0] 0b0: Configure the loop polarity of the PI controller