Keysight U8903B, Руководство по обслуживанию

Страница: 63 / 165

Performance Verification for Digital Generator and Digital Analyzer 4
Keysight U8903B Service Guide 63
Performance Verification
DSI master clock output frequency accuracy verification
This test measures the sampling rate accuracy on the DSI (Digital Serial Interface) master
clock output of U8903B using Keysight 53132A/53220A frequency counter to ensure that it
is within the published specification.
1 Connect the Keysight 53132A/53220A frequency counter input channel 1 to the
U8903B DSI MCLK output line using the DB25 to BNC cable as shown in
Figure 4-1 .
Figure 4-1 Keysight 53132A/53220A to DSI MCLK output for balanced DSI master clock output frequency
accuracy verification
2 Configure the Keysight 53132A/53220A frequency counter as follows:
– Preset the equipment
– Channel 1 input impedance: 50 Ω
– Frequency measurement start arming source: Immediate
– Frequency measurement stop arming source: Timer
– Frequency arming and measurement gate time: 0.3 s
3 Configure the U8903B digital output channel to be tested as follows:
– DSI output voltage: 3.3 V
– Reference clock source: Internal
– DSI audio resolution: 24 bits
– External reference clock word length: 32
– External reference clock multiplier: 128
– DSI data format: I2S
– DSI output bit clock sync edge: FALLing
– DSI Master Clock output state: ON
Table 4-2 DSI master clock output frequency accuracy specification
DSI master clock output frequency accuracy specification Equipment used
± 5 ppm Frequency counter
DB25 to BNC
cable
Keysight 53132A/
53220A frequency
counter
U8903B Balanced
DSI output
MCLK output