4 Setup Guide
This section provides descriptions of the hardware components that make up the PGA2505EVMV2. In addition,
configuration information for power supplies, analog input and output connections, switches, and jumpers are
provided.
4.1 Analog and Digital Power Supplies
All analog and digital power supplies are connected through terminal block J2, as shown in
Recommended power-supply connections are as follows:
• +VA and –VA are +5 V and –5 V, respectively
• Connect EGND to earth or chassis ground of the power supply
• Connect GND to common ground
• Leave VCC unconnected if using the
Figure 4-1. Power Terminal Block J2 Schematic
The PGA2505EVMV2 requires two analog supplies and one digital power supply. The analog supplies are VA+
and VA−, respectively. VA+ is typically set to +5.0 VDC, while VA− is typically set to −5.0 VDC. The analog
supplies power the
microphone preamplifier integrated circuit. The digital power supply, VCC, is
unconnected if using the
.
An optional third analog power supply may be used for the PGA2505 common-mode dc voltage input, VCOMIN
(pin 22). VCOMIN allows the PGA2505 output and input to be dc biased to a common-mode voltage between
0 V and 2.5 V, and is connected through terminal block J2. The common-mode voltage biases both the output
and input terminals of the PGA2505, with the output pins biased to the VCOMIN voltage level and the input pins
biased to approximately VCOMIN − 0.65 V.
The GND terminal of connector J2 serves as the common ground connection for both the analog and digital
sections of the PGA2505EVMV2. Connect the EGND (earth ground) terminal to the earth or chassis ground of
the power supply. The common ground (GND) and earth ground (EGND) are connected to one another using a
0.1-µF capacitor (C10).
Setup Guide
SBOU259 – OCTOBER 2021
PGA2505EVMV2 Evaluation Module
9
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