WM8734-EV1M 参数 Datasheet PDF下载

WM8734-EV1M

POWER SUPPLIES

Using appropriate power leads with 4mm connectors, supplies should be connected as described in

Table 1.

REF-DES

J1

J2

J4

J7

J3

J6

SOCKET NAME

DCVDD

+5V

DBVDD

AVDD

GND

AGND

SUPPLY

+1.42V to +3.6V

+5V

+2.7V to +3.6V

+2.7V to +3.6V

0V

0V

Table 1 Power Supply Connections

The DGND and AGND connections may be connected to a common GND on the supply with no

reduction in performance.

Note:

1.

As standard, designator L4 will be populated with a zero ohm link connecting the AVDD and

DBVDD supplies together reducing the amount of connections to the board. If a separate supply

is to be connected, L4 should be unpopulated and +2.7V to +3.6V should be connected to the

DBVDD panel socket (J4).

Refer to WM8734 datasheet for limitations on individual supply voltages.

2.

Important: Exceeding the recommended maximum voltage can damage EVB components.

Under voltage may cause improper operation of some or all of the EVB components.

BOARD FUNCTIONALITY

When using the DAC, there are three options for inputting digital data into the WM8734 evaluation

board. There is a coaxial input (J12) via a standard phono connector or an optical input (U1) via a

standard optical receiver module. A direct digital input is also available via one side of a 2x8 pin

header (H1).

When using the ADC, the analogue input signals are applied to the evaluation board via phono

connectors J11 (LLINEIN) and J13 (RLINEIN).

There are three options for outputting digital data from the WM8734 evaluation board when the ADC

is used. There is a coaxial output (J22) via a standard phono connector or an optical output (U6) via a

standard optical transmitter module. The digital signals output from the WM8734 may also be

accessed via one side of a 2x6 pin header (H2).

The analogue outputs of the board are via phono connectors J23 (LOUT) and J19 (ROUT).

All WM8734 device pins are accessible for easy measurement via the 10 pin headers (J10 & J15)

running up each side of the device.

The software control mode (i.e. SPI or 2-wire) is selectable via a 2-pin jumper connection (J8).

A level-shift IC (U3) is used to shift the fixed +5V digital input from the CS8427 (U5) down to the same

level as DBVDD. A transistor level-shift arrangement (Q1, Q2 & Q3) is used to shift the software

digital control lines from the PC (fixed +5V) to the same level as DBVDD.

w

Rev 1.2 November 2002

2