CS5542 CS5543

DS109PP2

25

CS5542 PIN DESCRIPTIONS

PDN - Power Down, Pin 11.

When asserted the CS5542 will enter the power-down state.

C[2:0] - ICAL Input Select, Pins 28, 27, 26.

In an array of 4 CS5542’s (eight channels), C2-C0 will select which channel is to receive the

d.c. current applied to the ICAL pins.

Digital Outputs Pins-

MDATA[3:0] - Modulator Data Outputs, Pins 25, 24, 21, 20.

The tri-level modulator data is output on MDATA3 - MDATA0 for decimation by the CS5543.

Modulator Output Coding Table

Overload

-1

zero

+1

MDATA3

MDATA2

MDATA_1

MDATA0

Value / Meaning

1

0

0

1

+1 / Normal operation

1

0

1

0

0 / Normal operation

1

1

0

0

-1 / Normal operation

0

1

1

0

+1 / Modulator Overload

0

1

0

1

0 / Modulator Overload

0

0

1

1

-1 / Modulator Overload

As shown in the table above, a constant number of zeros and ones exist for all output states.

This provides a data-independent noise invariant coding to maximize isolation between channels.

Analog Input Pins -

VREF-,VREF+ - Differential Voltage Reference Inputs, Pins 2, 3.

A differential voltage reference on these pins operates as the voltage reference for the CS5542.

Nominally, it is -4.0 V and + 4.0 respectively.

ICAL - Full-Scale Current Calibration Input, Pin 10.

ICAL needs to be supplied for full-scale gain calibration.

INL, INR - Input Left and Input Right, Pins 5, 8.

INL and INR are the left and right modulator current input pins.