ADS8588S: Please review the schematics of the ADC attached.

Hi NIKHITHA,

Please see my feedback about your schematic:

1. You have 3 different ground:  5V_GND, 3V3_GND, F ground for the capacitors on REFCAPA/B and REGCAP1/2. A solid ground plane (GND) is suggested for all of them, no FB1.

2. The pin REFGND_1 and REFGND_2 are floating now, both of them should be connected to the solid ground (GND) plane.

3. R691 value should be smaller than 1.5ohm, 0.22ohm is used on ADS8588SEVM.

4. C527 10uF capacitor should be placed close to the pin 42.

5. 1uF capacitors are suggested for REGCAP1 and REGCAP2, not 10uF.

6. A 10uF capacitor is suggested for REFCAPA/B, not 22uF.

7. A pull-up resistor is suggested between REFSEL (pin 34) and VCC_3V3.

8. 0.1uF capacitors can be used for all 5V and 3V3_GND supplies instead of 1uF, this is not too critical.

Best regards,

Dale

Hi,

Some comments are added based on your feedback. Could you please reply.

1) R691 placed is 0.22 ohm, which is smaller than 1.5 ohm.

2) Datasheet provides to use 1uF capacitors near 5V and 3V3_GND, not 0.1uF.

Hi NIKHITHA,

1. 0.22ohm resistor is good for R691.

2. There is no big difference by using 1uF or 0.1uF capacitors for decoupling on power supplies. You can keep 1uF capacitors.

Best regards,

Dale