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Datasheet

Datasheet

BD8271EFV

TSZ02201-0G1G0BK00250-1-2

© 2013 ROHM Co., Ltd. All rights reserved.

1.Oct.2013 Rev.002

www.rohm.com

TSZ22111・15・001

Noise Suppression

The following are possible causes of noise of the PWM driver.

A. Noise from Power Line or Ground

B. Radiated Noise

1. Countermeasures against A

(1) Reduce wiring impedance on 8V system power supply (SARNF1, SARNF2, VCC), 5V system power supply (VMFC) and

power GND (PGND1, PGND2) lines where high current flows. Make sure that they are separated from power supply

lines of the other devices so that they do not have common impedance. (Figure 5.)

Figure 5. Pattern Example

(2) Provide a low ESR electrolytic capacitor between the power terminal and the ground terminal of the driver to achieve

strong stabilization. Provide a ceramic capacitor with good high frequency property next to the IC. Also provide a

ceramic capacitor with good high frequency property between SARNF1, 2 and PGND1. (Figure 6.)

This can reduce power supply ripple due to PWM switching.

0.1µF

0.1µF

SARNF1,2

PGND1(Pin9)

SAVM

PGND1(Pin9)

Figure 6. Position of Ceramic Capacitors

Separate as much as

possible.

Other Devices