1. What is the maxim duty cycle of SI88621ED-IS (internal limit)?
2.How to work for PWM control from empty load to full load? The frequency is constant ?
3.The min PWM width is 250ns ? or other figure ?
What is the ESD class of Si86xx series parts?
Where would I find documentary evidence for this?
Hello every one
I'm designing a half bridge converter with input of 450V and 4KW power ( 250KHZ<Fsw<350KHZ) using sic mosfets like this or similar.
I'm thinking about using si8274 due to its high CMTI, Fast switching timings, suitable gate driver current and deat time control btw high and low side mosfets.
regarding using SIC MOSFET specifically, it is mandatory to pull down mosfet gate voltage to negative (-3 to -5) due to low Vth of sic mosfet.
Also fast switching will produce higher ringing that further mandates pulling the gate voltage to negative, to avoid false triggering of the gate.
my questions are,
1 - how to supply si8274 negative voltage for both high and low sides of the driver ?
2- how to add short circuit protection function, Like soft DESAT (usually used for IGBTs) to SIC mosfets?
appreciating any help
Currently, we are using below isolators in the same single PCB.
SI8661BB-B-IS1 = 2 nos
SI8662BB-B-IS1 = 1 no
We have given, supply voltage 5V and 3.3V DC from the DC/DC convertor.
As given in the datasheet, Do we need to use supply bypass capacitors for 3 IC's Seperately?
Since, 5V and 3.3V DC supplies are shared together, can we use bypass capacitors only for one IC?
Kindly give your valuable feedback.
Hello. Si890x has 0.5 PGA setting. Does it mean it's possible to measure input voltage greater than Vref? If not how can this gain to be used?
I am working on a simulation and I am new to using Ibis models.
I am using the model SI8261BXD_C_IS_30V_Driver_Type und Anode_Typ.
My Problem is how to understand which Pin are connected to what.
In the ibis file the pins are given:
[Pin] signal_name model_name R_pin L_pin C_pin
1 ANODE anode
2 NC NC
3 CATHODE GND
4 GND GND
5 VO driver
6 VDD POWER
but looking at the PSPICE Modell there are only driver typ INPUT, OUTPUT, ENABLE and the anode typ INPUT. How do I translate the pins?
Many thanks to any helpful answer!
1. The source and sink current of isolated driver of Si827x are 1.8A and 4A respectively, but the fall time is larger than the rising time. This phenomenon is quite different from drivers manufactured by TI, Maxim and so on.
2. The load used to test the rise and fall time of Si827x is only 200pF, while the typical capacitance of MOSFET or GaN are 1nF. Even with 200pF capacitance, the rise and fall time is still larger than the driver of LM5113 from TI whose source and simk current is 1.2A and 5A respectively with load capacitance 1000pF.
Can anybody help to explain this!
Re these points connected? and is there any application where I can get rid of the feedback circuit in an isolated design to reduce cost?