Application of ADC GX7606 (compatible with AD7606) in multiphase motor control

In the motor control system with DSP as the core, in order to realize real-time control of the system and system stability, the voltage and current quantity in the main circuit will be processed by the sensor with isolation effect, and then sent to the A/D sampling pin of DSP through the corresponding conditioning circuit. Due to the insufficiency of the DSP on-chip A/D sampling module in the range design and immunity capability, it is necessary to extend the off-chip A/D sampling chip, and the sampling accuracy and immunity capability of the A/D sampling chip are higher than that of directly using the on-chip resources of the DSP.

 

Therefore, for the DSP‘s on-chip A/D sampling module, its 0V~3V range limits the design of the hardware circuit, which will increase the debugging difficulty; it does not have its own signal interference processing, and in the processing of AC signals, the error is larger. This paper recommends the use of GX7606 chip for the peripheral hardware circuit. The ADC is an eight-channel 16-bit 200kSPS, which can replace ADI‘s AD7606.

 

GX7606 (compatible with AD7606) is a synchronous sampling analog-to-digital converter, each channel has a built-in analog input clamping protection, analog filter, programmable gain amplifier. The chip also integrates digital filters, a 3.5ppm/°C low-drift 2.5V precision reference voltage source and a 4.5V reference voltage buffer, and supports both parallel and serial interfaces.

 

The GX7606 (compatible with the AD7606) is powered by a single 5V power supply, with throughput rates up to 200kSPS for all eight channels, supports ±10V and ±5V true bipolar input ranges, has a 1MΩ analog input impedance, and input clamping protection for voltages up to ±30V with an ESD rating of up to 8kV. For applications requiring lower throughput rates, the GX7606 has a built-in oversampling mode and a flexible ESD rating of 8kV. For applications requiring lower throughput rates, the GX7606‘s built-in oversampling mode and flexible digital filters can be used to improve noise performance.

 

Key features of the GX7606 (AD7606 compatible): 

- Operating temperature range -40°C to +85°C, 5V single analog supply

- VDRIVE supply voltage 2.3V to 5V, ±30V input clamping protection, 8kV ESD

- 2nd order anti-alias analog filter, on-chip precision reference source and reference voltage source buffer

- True bipolar analog input range ±10V, ±5V, integrated digital filter oversampling function

- SNR 86dB (no oversampling) 95dB (64x oversampling)

- QFP-64 package 12mm x 12mm