Si9986 IC H-Bridge Driver Testing

[debugtimog]

Good day everyone.
I have an IC 3 pcs Si9986, Buffered H-Bridge Driver with Integrate MOSFET. I am testing it but so far it is either chan a is good but chan b is bad or the other way around. I am now questioning the way I am testing if correct. I hope you can point to me If I am doing something wrong.

Channel A connection. No other components connected, just the IC.
Sa = grounded
In A= Function Gen, 8VDC squarewave 1KHZ
Out A = Oscilloscpe

Channel B connection. No other components connected, just the IC.
Sb = grounded
In A= Function Gen, 8VDC squarewave 1KHZ
Out A = Oscilloscpe

Sample output on one of the IC's channel, sometimes chan a bad but chan b good. I did not have both channels bad or both channel good. Any suggestion on how to properly test the IC? Thanks.

 

[KlausST]

Hi,

I did not go into detail with your tests. But there are some general rules for testing. I´m not sure whether you followed them:
* ESD protextion: DUT, power supplies, measurement devices, desk surface, and operator need to be protected against ESD. This is not only unintentional static voltage, but also the voltage that is generated inside the power supplies with respect to EARTH GND.
* no (unused) input must be left floating.

Also I recommend to properly bypass every power supply close at the DUT.

Klaus

 

[BradtheRad]

Apparently you test each half-bridge separately, correct? Then connect outA to a midway voltage through a resistor. Measure voltage across the resistor.

Likewise outB.

 

[Easy peasy]

where are the caps on the chip ? might pay to read the data sheet ...(?)