Texas Instruments PGA2505EVMV2, Руководство пользователя

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Figure 1-2. PGA2505EVMV2 GUI
A 16-bit control word is utilized to program these functions; see Figure 1-3 .
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Data Ignored DC CM ZC OR D4 D3 D2 D1 0 0 G5 G4 G3 G2 G1 G0 Data Ignored
High Impedance DC CM ZC OR D4 D3 D2 D1 0 0 G5 G4 G3 G2 G1 G0 High Impedance
DC Servo Enable
(Active Low)
CM Servo Enable
(Active High)
Zero Crossing Detect
(Active High)
Over-Range Indicator Bit
(0 = 5.1VRMS, 1 = 4.0VRMS
Data for GPO4
Data for GPO3
Data for GPO2
Data for GPO1
Preamplifier Gain
where N = G[5:0]DEC
For N = 0
Gain = 0dB
For N = 1 to 17
Gain (dB) = 6 + 3N
For N = 18 to 31
Gain = 60dB
CS
SCLK
SDI
SDO
Figure 1-3. PGA2505 16-Bit Control
The differential analog output of the PGA2505 is constantly monitored by a dc servo amplifier loop. The purpose
of the servo loop is to minimize the dc offset voltage present at the analog outputs by feeding back an error
signal to the input stage of the programmable gain amplifier. The error signal is then used to correct the offset.
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4 PGA2505EVMV2 Evaluation Module SBOU259 – OCTOBER 2021
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