HOW TO USE AD7386 SEQUENCER MODE?

Question

There is a AD7386 in our custom board, 4 analog input channels， so seuqencer mode is used. But the sampled data tell us channel sequece is uncertainty, sometimes AinA0 and AinB0 are at the front, and somrtimes AinA1 and AinB1 are at the front. The registers are written at the following sequence: 
 0xa0ff 0x9400 0x0000 0x0000 0x0000 . . . 
 Could somebody tell me how to solve this question?

jcolao · Accepted Answer

Hi TRolan721, 
 The AD7386 has two ADCs(ADC A and ADC B) that samples data simultaneously. It also has a multiplexer that switches each ADC input (ADC A and ADCB) from its own channel 0 and channel 1. The AD7386 has two mode to switch the multiplexer either channel mode (CH bit) or sequencer mode (SEQ bit). The channel mode (CH bit) selects either channel 0 or 1 is selected on the respective ADC. The sequencer mode (SEQ bit) will have an alternate sequence of channel 0 and channel 1, that means it samples on the falling edge of CS on channel 0 and on the next falling edge of CS, it will then sample channel 1. Then the sequence continues until it is disabled. 
 In your register write sequence, I can see that you perform reset, followed by a write to configure register 1 enabling the sequencer mode then this is followed by suppose to be a read but an invalid register address (0x0000). The last write you made to the register which is enabling the sequencer mode, would give an alternating result of channel 0 and channel 1 of each ADC (ADCA and ADC B). 
 
 Regards, 
 Jonathan

HOW TO USE AD7386 SEQUENCER MODE?

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