CS5181
Supply Inputs
VA1+, VA2+ — Positive Analog Supply
Input for the positive analog supply is +5.0 V typical when AGND is 0 V.
AGND — Analog Ground
Analog ground for circuits supplied by VA+.
VD1+, VD2+ — Positive Digital Supply
Input for positive digital supply is +3.3 V typical when DGND is 0 V.
DGND — Digital Ground
Digital ground for circuits supplied by VD+.
Signal and Reference Related Inputs
AIN+, AIN- — Differential Analog Inputs
Fully differential signal inputs.
VREFIN — Voltage Reference Input
VREFOUT or an external reference is connected to VREFIN. Analog input voltage (full scale
fully differential peak-to-peak) into the converter is 1.6 times this value.
VREF+ — Positive Voltage Reference
Filter capacitor connection for the reference input buffer. The voltage on this pin equals
VREFIN X 1.6.
VREF- — Negative Voltage Reference
VREF- is connected to AGND.
VREFOUT — Voltage Reference Output
Output pin for the 2.375 volt on-chip reference relative to AGND.
VREFCAP — Reference Bypass
Filter capacitor connection for internal reference.
Serial Interface I/O Signals
SCLK, SCLK — Serial Interface Clock
Serial Clock Output. A gated serial clock output from the converter at a rate equal to 1/3 the
MCLK clock rate. The SCLK output is a complement of SCLK and helps reduce radiated
noise if the two lines are run adjacent on the PC board layout and drive a balanced load.
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DS250PP1