Technical Note

4/8

BH76106HFV, BH76109HFV, BH76112HFV, BH76206HFV

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2009.03 - Rev.A

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(9) Standby pin

When the standby pin is open, the LSI is in a standby state.

Since adding a voltage greater than Vcc at the standby pin turns a protective diode ON, make this at most Vcc+0.2 V

(no greater than Vcc+VF). (See Fig. 4) Applying a voltage to the standby pin when the voltage Vcc is not being

applied also turns the protective diode ON, so do not apply a voltage.

Responsiveness of Standby Control

STBY

STBY

(100% color bar signal)

(100% color bar signal)

Fig.5 Standby Response Characteristic

Fig.6 Standby Response Characteristic

※

In relation to IC startup, this is practically 0 μs.

※

In relation to IC shutdown, this is after approximately 2 μs.

Noise also does not occur when toggling the switch.

(10) Input coupling capacitor

Making the input coupling capacitor a value less than 0.1 μF (the recommended value) increases SAG. Determine

the capacitance of the input capacitor used after taking into consideration the relationship of SAG to input coupling

capacitor.

Fig.7

Moreover, if you make the input coupling capacitor a value greater than 0.1 μF (the recommended value), it may take

time for the output waveform to stabilize. Decide the value of the coupling capacitor used by referring to the results

shown in Fig. 10.

Approx. 0.7V

Diode ON

Fig.4

0

10

20

30

40

50

60

0.00

0.01

0.10

1.00

INPUT COUPLING CAPACITOR (μF)

Relationship of SAG to Input Coupling Capacitor

↑

↓△V

Δ

V : SAG

Vin

VOUT

0.1μF

Monitor

Vary the value of an

external capacitor and

check the bounds of the

output waveform

100μF

22μF

75Ω

VSAG

75Ω

1V

①

Vin

VOUT

Monitor

100μF

22μF

75Ω

VSAG

75Ω

③

②

STBY

Fig.8

Fig.9

(Startup characteristic, Vcc = 3.0 V)

(Shut down characteristic, Vcc = 3.0 V)