gozwei
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Hi!
I’m preparing minimal design for ADS1282 A/D converter from TI. My project is in development stage so I’m trying to keep all “modules” separate for easy reconfiguration. Last module I need is A/D I’ve mentioned.
Power source is for now separate module. My goal is to recreate geophone interface from figure 70 (page 42 of ADS1282 datasheet). I’m ready with +2.5V, -2.5V and +6.5V power supply. The geophone interface itself (Analog inputs) is simple – no question there. Problem starts with reference.
If I understand it correctly I should take REF5050 and connect it as follows:
It’s a bit confusing for me. What final reference do I get? It should by +2.5V and -2.5V, but I can’t see how it’s done here? Is this schematic OK?
Digital lines for SPI will be connected directly to goldpin that I’ll use for connection to uC module.
Second question is about clock. There are two clocks required – one for SPI (serial clock input driven by uC) and second for A/D itself (master clock input). What source of master clock do I need and how to connect it?
I realize that those are probably simple question, but I couldn’t find answers myself – please help
The mentioned schematic:
I’m preparing minimal design for ADS1282 A/D converter from TI. My project is in development stage so I’m trying to keep all “modules” separate for easy reconfiguration. Last module I need is A/D I’ve mentioned.
Power source is for now separate module. My goal is to recreate geophone interface from figure 70 (page 42 of ADS1282 datasheet). I’m ready with +2.5V, -2.5V and +6.5V power supply. The geophone interface itself (Analog inputs) is simple – no question there. Problem starts with reference.
If I understand it correctly I should take REF5050 and connect it as follows:
- Vin (pin 2) to +6.5V
- GND (pin 4) to -2.5V supply and to Vin through 1uF capacitor and to Vout via capacitors and finally to VREFN
- Vout via three capacitors and resistor to VREFP
It’s a bit confusing for me. What final reference do I get? It should by +2.5V and -2.5V, but I can’t see how it’s done here? Is this schematic OK?
Digital lines for SPI will be connected directly to goldpin that I’ll use for connection to uC module.
Second question is about clock. There are two clocks required – one for SPI (serial clock input driven by uC) and second for A/D itself (master clock input). What source of master clock do I need and how to connect it?
I realize that those are probably simple question, but I couldn’t find answers myself – please help
The mentioned schematic:
