# Recent content by jwfan

1. ### Strange Bode Plot form a constant on time DC-DC Converter

Hello, We got a strange bode plot for a constant on time DC-DC Buck converter. This converter shows the phase crosses the zero line at low frequency. This attached waveform is the simulation results of Simplis. the network analyzer shown the similar result. Both transient simulation and test...
2. ### Output capacitor of buck converter

OK, it is a big question. Let me try to answer it. 1. It's important to the whole transfer function of the power stage and will determin the compensation design. (Bandwidth is directly related to transient response) 2. The ESR will help the stability but will generate more ripple. For old...
3. ### Standard logic controlling a PNP transistor

Pay attention to the load resistor value, when you turn on the 3906, you may need to sink the base current out by using the standard logic.
4. ### How to compensate my LDO ?

LDO compensation Hi, Acturally, I cannot fully understand the circuit. especially about the second differential pair. Could you tell me the function of that? Looks like you have a lot of amplifier stages, which can easily cause stability problems. What I noticed is the way you did AC...
5. ### Total Power down mode current.....

Maybe you can check the leakage current on the PC board. Clean it first.
6. ### LDO stability with package parasitic inductance

What's the inductor value you are using for simulation? if you want accuracy, you may need some resistor in serias with this parasitic inductors. Maybe several mohms.
7. ### 0.2V Bandgap used in LM10 circuit calculation help

lm10 band gap calculation Hi, guys, I want to understand the bandgap circuit used in lm10, which is designed by Widlar in 70s. But it's not so easy. I upload the simplified circuit here. Hope you can help me. The circuit is below, Thanks a lot
8. ### why higher frequencies result in smaller components ?

High frequency makes the current ripple on inductor and the voltage ripple on capacitor smaller. So, smaller L/C can be used to achieve same ripple. With high frequency, the control bandwidth can also be pushed to higher frequency, the compensation compensation can be smaller, too.
9. ### help : Boost up voltage without using tansformer

If I have this machine, I will be the richest guy in world. :)
10. ### Could you help me for the 32-QFN leadframe diagram?

qfn leadframe Thanks a lot. I got it.
11. ### Could you help me for the 32-QFN leadframe diagram?

32-qfn footprint If you happens to have a 32-QFN leadframe diagram, could you send it to me. I need to draw a bonding diagram. Thanks a lot!
12. ### high precision, low offset cmos comparator

Using Bipolar devices, it is much easier. For CMOS, I 'm not sure. It will shown it has a big change range when you are doing Corner and Monte-Carlo Simulation for CMOS Comparator.
13. ### high precision, low offset cmos comparator

for continuous-time, I saw some products from TI with 0.5mV offset but the maximum value is 15mV. really hard, be sure to check the Monte-carlo simulation results
14. ### sense several microvolt,who can help me .3q

If you can give the application of this design, it may help us a lot. several microvolt is too small, even larger than the device noise.
15. ### Group Delay of a Filter

pspice group delay with the phase shift and frequency information of the filter, you can use the calculator of CADENCE to get the delay