[SOLVED] Non Inerting amplifier (mcp6004) gain problem

Hello there,

Designing a buffer and gain circuit for RTD and currently i have struck a wall.

Requirement
-give a gain of 5 to a signal coming from an RTD, to be given to an ADC

Implementation
-have used Microchip MCP6004, a quad amp IC. used one amp as a voltage follower and the other in a non inverting amplifier setup to give gain of 5, schematic attached for better understanding


problem
-the voltage follower side is working perfectly, but the gain stage is also acting like a perfect voltage follower.

things checked
-pcb is designed fine, the resister values shown between negative input and output (20.5k) and output to ground (5.1k) is present and connected properly, ground connections are fine.

-have checked 3 boards and all are the same


any help will be highly appreciated, as this basic issue has ruined my nights

R448 connected to output is useless here,
connect it to PIN 9 !

Hi,

wiring of OPAMP C is wrong:

output --> 20k5 --> 5k1 --> GND
center of 20k5 and 5k1 to -IN

Klaus