Texas Instruments ADS8402 EVM, ADS8412 EVM Power Supply Requirements, 1. Power Supply Test Points

Chapter 4

Power Supply Requirements

The EVM accepts four power supplies.

-A dual ±Vs dc supply for the dual supply op-amps. Recommend ±7 Vdc supply.

-A single +5-Vdc supply for the analog section of the board (A/D + Reference).

-A single +5-V or +3.3-Vdc supply for the digital section of the board (A/D + address decoder + buffers).

There are two ways to provide these voltages.

1) Wire in the voltages at test points on the EVM. See Table 4- 1.

Table 4- 1. Power Supply Test Points

Test Point	Signal		Description
TP14	+BVDD	Apply +3.3 V or +5 V. See ADC data sheet for full range.
TP11	+AVCC	Apply +5	Vdc.
TP12	+VA	Apply +7	Vdc. Positive supply for amplifier.
TP13	-VA	Apply –7 Vdc. Negative supply for amplifier.

2)Use the power connector J1 and derive the voltages elsewhere. The pinout for this connector is shown in Table 4- 2. If using this connector, set the W1 jumper to connect +3.3VD or +5VD from connector to +BVDD. Short between pins 1- 2 to select +5VD or short between pins 2- 3 to select +3.3VD as the source for the digital buffer voltage supply (+BVDD).

Table 4- 2. Power Connector, J1, Pinout

Signal	Power Connector - J1		Signal
+VA(+7V)	1	2	–VA (–7V)
+5VA	3	4	N/C
DGND	5	6	AGND
N/C	7	8	N/C
+3.3VD	9	10	+5VD

4-1