TMS320F280049C: PGA采样应用

pga_ex1_dac_adc_ext_loopback.c历程中PGA配置

void initPGA(void)
{
//
// Set a gain of 3 to PGA2
//
PGA_setGain(PGA2_BASE, PGA_GAIN_3);

//
// No filter resistor for output
//
PGA_setFilterResistor(PGA2_BASE, PGA_LOW_PASS_FILTER_DISABLED);

//
// Enable PGA2
//
PGA_enable(PGA2_BASE);
}

实际应用PGA有PGA_OF,和PGA_IN两种情况。历程中没有体现这种区别，怎么配置PGA是OUT还是IN

Susan Yang：

不知我是否对您的疑惑理解正确

在例程中，有如下说明，硬件上是连接  DACA_OUT (Analog Pin A0) 和  PGA1_IN 

The output of the DAC is externally connected to PGA1 for a 3x gain amplification. It uses two ADC channels to sample the DAC output and the amplified voltage output from PGA1. The ADC is connected to these signals internally.//! – Connect DACA_OUT (Analog Pin A0) to PGA1_IN (Pin 15 on HSEC connector of //! – CCard)//! – Connect PGA1NEG to GND 

//! This example generates 400 mV using the DAC output (it uses an internal
//! voltage reference). The output of the DAC is externally connected to PGA1
//! for a 3x gain amplification. It uses two ADC channels to sample the
//! DAC output and the amplified voltage output from PGA1. The ADC is connected
//! to these signals internally.
//!
//! \b External \b Connections \n
//!- Connect DACA_OUT (Analog Pin A0) to PGA1_IN (Pin 15 on HSEC connector of//!- CCard)
//!- Connect PGA1NEG to GND