ucc27211ddar fault analysis -...
TRANSCRIPT
UCC27211DDAR fault analysis
Picture of IC; Sourced from Arrow electronics:
Bottom side :
Measurement setup:
PWM ~237 kHz
50% duty cycle
Vin 29.59 V
Expected output voltage VIN / 2
Oscilloscope probe impedance 1M
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Schematic:
NOTE: VIN has 5x 100V 2.2uF ceramic capacitors on the input. These are out of view in this picture.
Measurements real IC
Picture 1:
Picture name: 171028_104606.jpg
Load 0.000A
Measured current: 0.001A
Measured vout: 14.17V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 2:
Picture name: 171028_105238.jpg
Load 0.100A
Measured current: 0.101A
Measured vout: 14.09V
NOTE: purple trace was disconnected. It was the same as the previous picture
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 3:
Picture name: 171028_105641.jpg
Load 0.200A
Measured current: 0.201A
Measured vout: 14.01V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 4:
Picture name: 171028_105739.jpg
Load 0.250A
Measured current: 0.251A
Measured vout: 13.98V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 5:
Picture name: 171028_105905.jpg
Load 0.270A
Measured current: 0.270A
Measured vout: 8.16V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 6:
Picture name: 171028_110007.jpg
Load 0.300A
Measured current: 0.300A
Measured vout: 7.32V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 7:
Picture name: 171028_110112.jpg
Load 0.500A
Measured current: 0.500A
Measured vout: 0.25V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 8:
Picture name: 171028_110241.jpg
Load 1.00A
Measured current: 0.83A
Measured vout: 0.10V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Measurements of fake ?? IC Source: TAOBOA (China)
Probably fake ?
Markings:
27211
68K
APOR G4
Picture of bottom ic:
NOTE: Nothing has changed in the measurement setup other than putting the fake?? IC on the board
Picture 9:
Picture name: 171028_113326.jpg
Load 0.000A
Measured current: 0.001A
Measured vout: 14.19V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 10:
Picture name: 171028_113437.jpg
Load 0.100A
Measured current: 0.101A
Measured vout: 14.13V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 11:
Picture name: 171028_113519.jpg
Load 0.200A
Measured current: 0.201A
Measured vout: 14.06V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 12:
Picture name: 171028_113617.jpg
Load 0.250A
Measured current: 0.251A
Measured vout: 14.03V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 13:
Picture name: 171028_113654.jpg
Load 0.270A
Measured current: 0.270A
Measured vout: 14.02V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 14:
Picture name: 171028_113724.jpg
Load 0.300A
Measured current: 0.300A
Measured vout: 14.00V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 15:
Picture name: 171028_113817.jpg
Load 0.500A
Measured current: 0.500A
Measured vout: 13.93V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 16:
Picture name: 171028_113844.jpg
Load 1.00A
Measured current: 0.998A
Measured vout: 13.79V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 17:
Picture name: 171028_113928.jpg
Load 2.00A
Measured current: 1.998A
Measured vout: 13.64V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 18:
Picture name: 171028_114017.jpg
Load 3.00A
Measured current: 2.997A
Measured vout: 13.52V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10
Picture 19:
Picture name: 171028_114116.jpg
Load 6.00A
Measured current: 6.000A
Measured vout: 13.20V
Pin: Probe mode:
yellow: HS X10
blue: LO X1
Purple: HB X10
green: HO X10