CSD25401Q3

Jason Yow

Other Parts Discussed in Thread: LMH6554

NewBie in the Spice Simulation.

Have build a simple circuit to use CSD25401Q3 PMOS as a switch to OPEN / CLOSE path to charge the capacitors.

By pulling Gate of PMOS to 5V, PMOS should open. (S-gate and D-gate should open)

From Transient Simulation, it shown the path still CLOSE, and continue charging capacitors.

Any thing i set it wrongly?

simulation.zip

0 Jason Yow over 13 years ago

nevermind.

Drain and Source Gate was inversely design.

Issue solved

0 Garima Ojha over 12 years ago in reply to Jason Yow

I am new at circuit designing, Please help.

I have made a circuit using CSD25401Q3 as a laser driver to generate ultra short pulses.

LMH6554 is used to generate short pulses of width 50-100 ns, I have fed the output of LMH6554 as a gate input to mosfet.

My problem is that the drain current of mosfet has a pulse width of 500 ns. Why a 50-100 ns pulse gate input is generating 500 ns current pulse?

I have attached the simulation files.

laser driver.TSC

0 Brett Barr1 over 12 years ago in reply to Garima Ojha

Garima,

While I am not certain, I think your issue might be with the Op Amp. The guys over in that forum might be more help to you.

Power management forum