The document describes an audio interface product called BU7843AGU for cellular phones. It features a 6x6 keyscan circuit.
The BU7843AGU is a silicon monolithic integrated circuit designed as an audio interface for cellular phones, featuring a 6×6 keyscan circuit and multiple analog and digital supply pins. The document details its structure, features, absolute maximum ratings, and recommended operating conditions.
Key sections include electrical characteristics such as supply voltage ranges, input currents, and power dissipation, as well as a pin‑layout diagram and extensive cautions on power‑supply handling, grounding, and PCB design to ensure reliable operation.
| Analog supply voltage (AVDD) | -0.3 > 4.5 V |
|---|---|
| Digital supply voltage (DVDD) | -0.3 > 4.5 V |
| Power supply voltage (PVDD) | -0.3 > 4.5 V |
| Operating temperature range | -30 °C to +85 °C |
| Input current (IN) | -10 to +10 mA |
| Allowable dissipation (Pa) | 310 mW |
| Recommended analog voltage (AVDD) | 2.7 – 3.1 V |
| Recommended digital voltage (DVDD) | 1.65 – 3.1 V |
| Recommended power voltage (PVDD) | 2.7 – 3.1 V |
The recommended analog operation voltage for AVDD is 2.7 V to 3.1 V.
The absolute maximum ratings for AVDD, DVDD, and PVDD are –0.3 V to 4.5 V.
A reverse connection of the power‑supply connector can break down the IC, so an external diode should be used for protection.
The device operates from –30 °C up to +85 °C.