Technical Note

9/16

BH76906GU, BH76909GU, BH76912GU, BH76916GU, BH76706GU

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2009.03 - Rev.A

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1) Decoupling capacitor only

1) Decoupling capacitor only

2) Decoupling capacitor + 10 Ω resistor

2) Decoupling capacitor + 10 Ω resistor

A

A

B

Vcc

Vcc

A

A

A

C

Vcc

Vcc

A

B

A

Waveform of current between

power supply and capacitor (A)

10 mA/div

Waveform of current between

capacitor and IC (B)

10 mA/div

Waveform of current between

power supply and capacitor (A)

10 mA/div

Waveform of current between

resistor and capacitor (B)

10 mA/div

Waveform of current between

capacitor and IC (C)

10 mA/div

Other

VIDEO

AMP

Chrarge Pump

-Vcc

1uF

1uF

3.3uF

Vcc

Vcc pin

Fig.12 Effects of Charge Pump Circuit Current Ripple on External Circuit

Fig.13

1. Current ripple due to charge pump

circuit affects power supply Vcc pin

2. Current ripple affects

DAC or other

Fig.14