At power up, we keep the ADC in power down mode with the pin 50 (PDN).
We tried the following sequence over SPI to wake up the chip, but did not succeed.
#ADS54Jxx_ANALOG
W 0x0000 0x81 //Register 0x00 (address = 0h); bit(7) := RESET = '1' = Internal software reset, clears back to 0; bit(6:1) := not used = '000000'; bit(0) := RESET = '1' = Internal software reset, clears back to 0
W 0x0011 0x80 //Register 0x11 (address = 11h); bit(7:0) := ANALOG BANK PAGE SEL = '0x80' = Master page
W 0x0020 0x00 //Register 0x20 (address = 20H), Master Page (080h); bit(7-4) := PDN ADC CHA = '0x0' ; bit(3-0) := PDN ADC CHB = '0x0' = Both Channels Power Up Mask 1
W 0x0021 0x00 //Register 0x21 (address = 21h), Master Page (080h); bit(7-6) := PDN BUFFER CHB = '0b00' ; bit(5-4) := PDN BUFFER CHA = '0b00' = Both buffers Power Up Mask 1
W 0x0026 0x40 //Register 0x26 (address = 26h), Master Page (080h); bit(7) := GLOBAL PDN = '0' = Normal operation; bit(6) := OVERRIDE PDN PIN = '1' = Ignores inputs on the power-down pin ; bit(5) := PDN MASK SEL = '0'; bit(4:0) Must write 0 := '0x00'
W 0x0026 0xC0 //Register 0x26 (address = 26h), Master Page (080h); bit(7) := GLOBAL PDN = '1' = Global power-down via the SPI; bit(6) := OVERRIDE PDN PIN = '1' = Ignores inputs on the power-down pin ; bit(5) := PDN MASK SEL = '0'; bit(4:0) Must write 0 := '0x00'
W 0x0055 0x00 //Register 0x55 (address = 55h), Master Page (080h); (7-5) := not used = '00' bit(4) := PDN MASK = '0' = Normal operation; (3:0) := not used = '00000'
W 0x0059 0x20 //Register 0x59 (address = 59h), Master Page (080h); bit(7) := FOVR CHB = '0' = Normal operation; bit(6) := not used = '0'; bit(5) := ALWAYS WRITE 1 = '1'; bit(4:0) := not used = '00000'
The whole initalisation we do is in the following file:
adc_init.cfg
