Applications information, Power-supply decoupling, Open-drain pins – Rainbow Electronics MAX34441 User Manual

Page 51: Power-supply decoupling open-drain pins

PMBus 5-Channel Power-Supply Manager

and Intelligent Fan Controller

MAX34441

Applications Information

Power-Supply Decoupling

To achieve the best results when using the device,
decouple the V

power supply with a 0.1FF capacitor.

Use a high-quality, ceramic, surface-mount capacitor
if possible. Surface-mount components minimize lead
inductance, which improves performance, and ceram-
ic capacitors tend to have adequate high-frequency
response for decoupling applications.
Decouple the REG25 and REG18 regulator outputs using
1FF and 10nF capacitors (one each per output).

Open-Drain Pins

MSDA, MSCL, SCL, SDA, FAULT, and ALERT are open-
drain pins and require external pullup resistors con-
nected to V

to realize high logic levels.

PSEN0 to PSEN4 can be user-configured as either
CMOS push-pull or open-drain outputs. When config-
ured as open-drain, external pullup resistors connected
to V

are required to realize high logic levels (see the

MFR_MODE settings).