Press Release Summary:
Accommodating compact, portable equipment put to continuous use that requires extended operating times from one battery, BU7150NUV supports operating power supply ranges of 0.93-3.5 V and 1.03-3.5 V. Automatic startup sequence control circuit, power ON reset function, and clicking/popping noise reduction circuit promote optimal performance, while 1 mA operation promotes battery life. Other features include thermal shutdown circuit and selectable BTL connection.
Original Press Release:
Low Power Headphone AMP
Compact portable equipment put to continuous use, such as IC recorders, electronic dictionaries, and portable audio players, require longer operating times from a single battery. To meet this need ROHM offers the BU7150NUV headphone amp capable of operation from only 0.93V.
(0.93V to 3.5V, Ta=0ºC to 85ºC)
(1.03V to 3.5V, Ta=-40ºC to 85ºC)
Key Feature 1: Wide operating voltage range (0.93V to 3.5V) enables operation from one or two batteries
The wide operating voltage range supports operation from one or two batteries. In addition, BTL connection allows the BU7150NUV to be used as a high-output monaural speaker amp. Additional features include an automatic startup sequence control circuit, power ON reset function, and clicking/popping noise reduction circuit for high-performance operation.
Key Feature 2: Low voltage, low current (1mA) operation results in longer battery life
The BU7150NUV features low 1mA current consumption and a wide voltage range (0.93V to 3.5V). When operating from a single battery, conventional headphone amps require a step-up circuit, which increases power consumption as well as loss (through step-up operation). In contrast, the BU7150NUV eliminates the need for a step-up circuit, reducing power consumption for longer battery life.
Conventional Class AB Amp BU7150NUV
Supply Voltage (typ) 3V 1.5V
No-Signal Current 5.0mA 1.0mA
Power Consumption 15.0mW 1.5mW
DC/DC Efficiency 90% -
Total Power Consumption 16.7mW 1.5mW
Key Feature 3: Built-in startup sequence circuit reduces load and controls clicking noise
A startup sequence circuit is built in to ensure high fidelity audio output during ON/OFF operation. Clicking/popping noise reduction is automatically performed, elminating the need for microcontroller control. In addition, the power ON reset function is not dependent on the supply voltage startup slew rate, simplifying use considerably.