My VF61 V1.1B not powering up

we are using VF61 256MB IT V1.1B with Irise Rev 1.1A Toradex Carrier board
my VF61 module not powering ON while giving 12V to Iris board. but my Iris board is working fine i cross checked with my other module.

  1. Where the problem causing in VF61?
  2. Which IC is giving problem in VF61?
  3. Which IC & where i want to probe to solve?
  4. Is there any module schematic for debugging?
  • Could you please define " VF61 module not powering ON"?
  • Did you follow steps described here - Quickstart Guide - Toradex
  • Are you able to see any output on debug serial port?

Hi alex.tx,

I followed the steps you mentioned . The board was working one. I connected my VF61 Board to the iris board as soon as the supply is turned on the power LED is turning on and off instantly . After this VF61 board is not at all responding (Iris board is working fine). I’m stuck with this issue i’m not clear with the issue with the board. What are the possible problems with this VF61. Can you help me the possible issues & how can i move forward to fix this issue. Any documentation or schematics will be helpful for me to run the hardware checks. Any help will be appreciated.

Thanks & Regards Girish


Please understand that we cannot share the schematic diagrams of our modules. First of all, it is important to know whether the main 3.3V input rail of the module is still coming from the carrier board. You can either measure this rail on the carrier board or on the module on the left side of C116. The VFxx module features one buck converter (IC11) which creates a 1.5V rail for the RAM as well as for the core regulator. You can measure this rail at the transistor T7 on pin 2. The bipolar transistor T7 is a regulator for the core voltage. Depending on the CPU load, the voltage is around 1.2V. You can measure it on pin 3 of the transistor.

Please measure these three voltages and let me know their value.

Hi Peter,
As per your references i probed the all voltage signals …but i am not getting any voltages at C116 & C7 ,

  1. Before connecting module i connected 12V to Iris board, its turning ON power.
  2. I connect my VF61 module (without power), and given 12V supply, then suddenly turning off automatically.
  3. But when i connect my other working module its working fine.
  4. List item what is the problem in my module


Please correct me if I did not understand you correctly. If you plug in another module or if there is no module in the Iris carrier board, the 3.3V main voltage is available. But as soon as the defective module is plugged in, there is no 3.3V. Is that correct?

If that is correct, could you measure whether the module creates any short on the 3.3V rail? Please measure the resistance between the 3.3V rail (e.g. measured at the left side of C116) and ground (e.g. available at the thermal pad of the not assembled IC11).