First timer...
I created a PCB layout (attached) using PCBExpress. I received the boards, soldered in the parts...and I'm less than pleased. Issues that I'm seeing:
*There appears to be a short between the +DC Pin and ground. I've removed all components that could possibly link this pin to ... anything, and I'm still getting voltage. Additionally, the resistance between this pin and ground is a little less than 1K. Is it common for PCBs to have this kind of short?
*The HEX IC is getting extremely hot. I'm using a CD4572UBE and connected per the attached diagram. I am wondering if the heat is due to oscilations in the chip due to the issue above bleeding a ~5V signal (connection between R13 and pin 12).
*The backup battery power supply are two 9V batteries hooked up in series; however, the voltage as seen by the voltage regulator is only about 7V rather than the expected 12V. The voltage seen at the ICs are hovering around the 5V mark.
Any guidance on how I should trouble shoot this would be most helpful. I have tested the other two boards that cam with the order, and I do not have any 'shorting' issue as described in the first bullet.
I created a PCB layout (attached) using PCBExpress. I received the boards, soldered in the parts...and I'm less than pleased. Issues that I'm seeing:
*There appears to be a short between the +DC Pin and ground. I've removed all components that could possibly link this pin to ... anything, and I'm still getting voltage. Additionally, the resistance between this pin and ground is a little less than 1K. Is it common for PCBs to have this kind of short?
*The HEX IC is getting extremely hot. I'm using a CD4572UBE and connected per the attached diagram. I am wondering if the heat is due to oscilations in the chip due to the issue above bleeding a ~5V signal (connection between R13 and pin 12).
*The backup battery power supply are two 9V batteries hooked up in series; however, the voltage as seen by the voltage regulator is only about 7V rather than the expected 12V. The voltage seen at the ICs are hovering around the 5V mark.
Any guidance on how I should trouble shoot this would be most helpful. I have tested the other two boards that cam with the order, and I do not have any 'shorting' issue as described in the first bullet.
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