Keysight U8903B - Page 66

4 Performance Verification for Digital Generator and Digital Analyzer
66 Keysight U8903B Service Guide
d Set the digital output sampling rate to 48 kHz.
e Set the DSI audio resolution based on the Word Length as given in “Test record for
DSI master clock output frequency accuracy verification” on page 128.
f Set the DSI audio word length to 32 bits.
g Set the Digital Output Sampling Rate based on the sampling rate (Hz) as given in
“Test record for DSI master clock output frequency accuracy verification” on
page 128.
h Set the DSI Master Clock Multiplier based on the Master Clock Multiplier as given in
“Test record for DSI master clock output frequency accuracy verification” on
page 128.
i Measure the Master Clock Rate twice and average the two measurements.
j Record the average Master Clock Rate, F
measure
in the “Test record for DSI master
clock output frequency accuracy verification” on page 128.
k Compute the master clock error using the following equation. MCLK is the master
clock rate calculated where MCLK = MUL × Sampling Rate (Hz).
Δ F
error
ppm = [(F
measure
– MCLK) / MCLK] × 1000000
8 Verification steps for word length at 24 bits:
a Set the DSI audio resolution to 24 bits.
b Set the DSI audio word length to 24 bits.
c Set the DSI Master Clock multiplier to 192.
d Set the digital output sampling rate to 48 kHz.
e Set the DSI audio resolution based on the Word Length as given in “Test record for
DSI master clock output frequency accuracy verification” on page 128.
f Set the DSI audio word length to 32 bits.
g Set the Digital Output Sampling Rate based on the sampling rate (Hz) as given in
“Test record for DSI master clock output frequency accuracy verification” on
page 128.
h Set the DSI Master Clock Multiplier based on the Master Clock Multiplier as given in
“Test record for DSI master clock output frequency accuracy verification” on
page 128.
i Measure the Master Clock Rate twice and average the two measurements.
j Record the average Master Clock Rate, F
measure
in the “Test record for DSI master
clock output frequency accuracy verification” on page 128.
k Compute the master clock error using the following equation. MCLK is the master
clock rate calculated where MCLK = MUL × Sampling Rate (Hz).
Δ F
error
ppm = [(F
measure
– MCLK) / MCLK] × 1000000