Datasheet

4-1
Power Supply Requirements
Power Supply Requirements
The EVM accepts four power supplies.
- A dual ±Vs DC supply for the dual supply op amps. Recommend a ±6-VDC
supply.
- A single +5.0-VDC supply for analog section of the board (A/D + Refer-
ence).
- A single +5.0-V or +3.3-VDC supply for 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
TP12 +BVDD Apply +3.3 V or +5.0 V. See ADC data sheet for full range.
TP10 DGND Digital ground
TP9 +AVCC Apply +5.0 V.
TP5 +VA Apply +6.0 V. Positive supply for amplifier.
TP3 −VA Apply –6.0 V. Negative supply for amplifier.
TP4 AGND Analog ground
2) Use the power connector J3, and derive the voltages elsewhere. The
pinout for this connector is shown below. If using this connector, set the
W1 jumper to connect +3.3 V or +5 V from connector to +BVDD. Short W1
between pins 1−2 to select +5 VD, or short between pins 2−3 to select
+3.3 VD as the source for the digital buffer voltage supply (+BVDD).
Table 4−2.Power Connector, J3, Pinout
Signal Power Connector − J1 Signal
+VA (+6 V) 1 2 –VA (–6 V)
+5 VA 3 4 N/C
DGND 5 6 AGND
N/C 7 8 N/C
+3.3 VD 9 10 +5 VD
Chapter 4