I am currently troubleshooting a single EVAL-AD4030-24FMCZ board with a customized MCU Evaluation Board, using guidance from the AD463x driver library.
- EVAL-AD4030-24FMCZ board is manually powered with 12V Supply.
- Signal RST_FMC has a 20k pullup to VADJ.
- For now, MCU Eval board is using 1 MHz SPI clock to do 1-lane SPI transactions.
The issue I am observing is inactivity from ADC(SDO0_FMC) in conversion mode after powerup [default].
SDO0_FMC stays logic-high throughout each1-lane SPI transactions. BUSY_FMC and all other 1-lane SPI FMC signals (CS, SCK, SDI) appear to be functional.
I have attached a few scope shots as reference with observation summary listed below.
What is reason for inactivity on SDO0_FMC? What can be done to fix this issue?
Scope Shot Observations
Setup:
- CH1 (Yellow): CNV_FMC
- CH4 (Green): BUSY_FMC
- CH2 (Blue): SDO0 (going to MCU-MISO)
- CH3 (Magenta): CS_FMC
Collected Scope Shot (#1)
- 1A: Test Conversion then 1st SPI Transaction sequence after Power-Up
- ADC in Conversion mode by default (per datasheet)
- 1B: (Closeup) BUSY_FMC responds after CNV_FMC rising edge as expected
Repeated Scope Shot (#2) with CH4 (Green) connected to SCK_FMC instead of BUSY_FMC
- 2A: 1st SPI Transaction sequence after Power-Up
- Hi-Pulse ADC-Convert and ADC Read Test
- No Sdo0-to-MISO activity observed (CH2 stays high)
- 0xFFFFFFFF read as result
- 2B: SPI Transaction Closeup (see above)