High power speaker amp ICs for advanced instrument clusters

1 min read

ROHM has announced AEC-Q100 qualified 2.8W output Class AB monaural speaker amplifiers for instrument clusters, used in vehicles equipped with autonomous driving and ADAS.

The BD783xxEFJ-M series (BD78306EFJ-M, BD78310EFJ-M and BD78326EFJ-M) is intended for vehicle clusters - requiring various sound outputs at high volume, including warning sounds, turn signals, welcome tones and voice guidance.

Also, by adopting a new type of over current protection (OCP) circuit the series can provide protection against output shorts (damage due to accidental terminal contact) to deliver high 2.8W output that was difficult to achieve in the past, making it possible to deliver high 2.8W output. In addition to over current protection, built-in thermal shutdown and under voltage lock out (UVLO) ensures high reliability protection against abnormal conditions.

Furthermore, satisfying the automotive reliability standard AEC-Q100 and having the capability of withstanding high temperature operation up to 105°C, enables stable voice output without affecting functionality even under severe conditions.

Key feature include:

1. High 2.8W output with built-in over current protection
With conventional over current protection circuits, the maximum output is limited, since the operating threshold of the protection circuit must be set to a value smaller than the maximum current the speaker amp can provide. ROHM’s new over current protection circuit eliminates the need to limit the output by preventing waveform distortion even at high output. This allows the BD783xxEFJ-M series to provide over current protection from output shorts which was difficult to achieve in the past in combination with high output (2.8W max. at 4Ω load and 10% distortion).

2. Ensuring high reliability in vehicle applications
The BD783xxEFJ-M series is qualified to withstand automotive reliability standard AEC-Q100 and supports a maximum operating temperature of 105°C. At the same time, adopting a power package reduces heat generation even at high volumes, resulting in stable audio output without compromising functionality - even under severe conditions. In addition to over current protection, thermal shutdown and under voltage lock out are built in - preventing damage caused by abnormal heat generation and unexpected popping(cracking) noise during battery interruptions.

ROHM’s BD783xxEFJ-M series speaker operational amps are mounted on Cypress Semiconductor’s Traveo Cluster MCU Family S6J3360 Series Evaluation Board for automotive applications, allowing for easy evaluation under conditions similar to real cases.