Overview
The LA4589W is a 1.5V stereo headphone preamplifier and power amplifier IC that provides all the functions of a complete playback system in a single chip, making it idealfor battery-powered, portable cassette players.
The LA4589W incorporates a metal/normal-tape equalization preamplifier, a power amplifier dual power supply ripple filters, a reference voltage amplifier that enables small-value (under 1 µF) virtual-earth capacitors to be used, and a system controller.

FEATUREs
• Single-pin control bass boost.
• Automatic music search (AMS).
• Preamplifier inputs for auto-reverse tape mechanism.
• Single-pin control forward/reverse playback selection.
• Two, on-chip, ripple filters.
• Selectable, single or dual ripple filter operation.
• Metal- and normal-tape modes.
• Power amplifier mute function.
• On-chip reference voltage amplifier.
• No power amplifier output capacitors required.
• 73dB (typ) preamplifier open-loop voltage gain.
• 21mW (typ) output power with bass boost.
• Built-in noise reduction capacitors.
• 0.95 to 2.2V supply.
• 48-pin SQFP.