P9235A-RB Layout Guide
© 2019 Integrated Device Technology, Inc
9
March 19, 2019
VCC5V V
IN
, VCC5V, LDO33, LDO18, VBRG_IN, PE Circuit and DRV_VIN Pin
Capacitors
The VCC5V node, V
IN
, LDO33, LDO18, VBRG_IN, and DRV_VIN pin capacitors (C42, C50, C53, C34, C35) are used to stabilize internal
voltage supplies used for normal operation. These capacitors must be located close to the P9235A-RB. A 10µF decoupling capacitor is
recommended to be placed as close as possible to GND from the V
IN
, VCC5V, and DRV_VIN nodes. A 1µF decoupling capacitor is
recommended for LDO33 and LDO18 regulated output pins. A 0.1µF capacitor is also recommended in parallel with aforementioned
decoupling capacitor. This will reduce the ESR of the decoupling which will reduce noise at the pin. VBRG_IN requires a 0.1µF capacitor
only.
Figure 8. V
IN
, VCC5V, LDO33, LDO18, VBRG_IN, and DRV_VIN Pin Capacitors Placed Close to
P9235A-RB with 0.1µF Placed Closest
6
1:Cin(C42)
3:Cout,LDO33(C50)
4:Cout,LDO18(C53)
6:Cdrv,vin(C34,35)
1
3
4
6
