ICM-42688-P Accelerometer Self-Test Ratio Exceeding ±14%

Hi all,

I'm currently validating the accelerometer self-test results on the ICM-42688-P, and I’ve encountered an issue where the self-test response ratio falls outside the expected ±14% range after applying specific sensor configurations.

Sensor Configuration

ODR:200 kHz
FSR:2g
Accelerometer Filter:3rd-order

Self-Test Validation Method:

I’m following the MPU-6000 datasheet self-test approach, which uses factory-programmed OTP self-test codes to estimate the expected self-test delta. Here's how I’m performing the calculation:

1. ST Codes (OTP values):
ST_CODES = [33, 43, 148] read from bank2 registers address 3B,3C,3D[XA_ST_DATA, YA_ST_DATA, ZA_ST_DATA]

2. Factory Trim Calculation:
BASE = 2620.0
factory_trim = BASE * (1.01 ** (st_code - 1)) + 0.5

3. Delta Calculation:
delta = ST_on_output - ST_off_output

4. Ratio Check:
ratio = (factory_trim - delta) / factory_trim

The self-test is considered a pass if the Change from factory trim is within ±14% for each axis.(mention in pg no-12)

Issue:

After applying the above configuration and methodology, I’m seeing that all axis self-test ratios are falling outside the ±14% threshold, leading to a failure in validation.

Request:

Has anyone observed similar behavior with this device, particularly under high ODR (200 kHz) or specific filter configurations? Any insights into:
Whether this validation method is applicable to the ICM-42688-P
Potential adjustments or considerations when interpreting self-test results for this device would be greatly appreciated.