Technical Note

11/16

BU7150NUV

www.rohm.com

2011.05 - Rev.C

© 2011 ROHM Co., Ltd. All rights reserved.

[Operation mode]

・

Selecting operation mode

BU7150NUV has two OPAMP in the IC (Fig. 1). BU7150NUV is selected for BTL-mode for mono speaker and

single-ended mode for stereo headphone operation. Mode is composed of external parts and internal control (Fig. 34, 35)

BU7150NUV operates at single-ended mode when MODE pin (pin8) = 0V turn on. BTL mode is operated when MODE

pin (pin8) = VDD turn on. BYPASS voltage = 100mV then operation mode is decided by internal comparator by detecting

MODE voltage.

The difference between Single-ended mode and BTL-mode is mentioned in the following table.

Parameter

Single ended mode

MODE='VSS'

BTL mode

MODE='VDD'

Mute function

enable

disenable

Bypass voltage turn on time [Ts1, Tb1, Tb3]

Ts1=2.82sec

Tb1=598msec

Tb3=256msec

Time until Signal Output [Ts2, Tb2,

Ts2=2.89sec

Tb1=668msec

Tb3=326msec

Maximum Output Power (THD=1%)

14mW

85mW

Total Harmonic Distortion + Noise

0.10%

0.20%

Power Supply Rejection Ratio

66dB

62dB

(Ta=25℃, VDD=1.5V, f=1kHz)