z9u2k
Member level 1
Hey,
My circuit is a very simple uC controlled solenoid.
The board is powered from three AA batteries, and managed by a PIC12F629. The PIC simply controls a MOSFET gate, that short-out the batteries across the solenoid once every five minutes or so, for about 30ms. (The solenoid requires a few Amps of current to operate).
Problem is, every time the solenoid gets activated the PIC gets a reset by the Brown-Out Detection.
The PIC has a 100pF bypass capacitor near its Vdd and Vss, and delivers current to the MOSFET's gate through a 330Ω resistor. (Qg is about 20nC)
I suspect that the fact the RDSon of the MOSFET is 50mΩ causes too much current to choose this path and the PIC's Vdd voltage drops too low.
I'm not sure what to do about this...
Thanks in advance, help appreciated.
My circuit is a very simple uC controlled solenoid.
The board is powered from three AA batteries, and managed by a PIC12F629. The PIC simply controls a MOSFET gate, that short-out the batteries across the solenoid once every five minutes or so, for about 30ms. (The solenoid requires a few Amps of current to operate).
Problem is, every time the solenoid gets activated the PIC gets a reset by the Brown-Out Detection.
The PIC has a 100pF bypass capacitor near its Vdd and Vss, and delivers current to the MOSFET's gate through a 330Ω resistor. (Qg is about 20nC)
I suspect that the fact the RDSon of the MOSFET is 50mΩ causes too much current to choose this path and the PIC's Vdd voltage drops too low.
I'm not sure what to do about this...
Thanks in advance, help appreciated.