BD3861FS

Audio Special Purpose Overview

The BD3861FS is a high-performance audio sound processor designed for home audio and mini-component systems. It features a stereo input with 5 selectable sources, a built-in 3-band equalizer (Bass, Middle, Treble), and independent front/rear volume controls. The device operates on a single supply voltage of 6.5V to 9.5V with a typical quiescent current of 13mA. It utilizes a 2-wire serial interface for control and achieves high signal-to-noise ratio through a 2-stage volume configuration.

Audio Special Purpose Feature Summary

• Built-in 3-band tone control: Bass, Middle, and Treble.
• Stereo input with 5 selectable channels and independent input selection.
• Front Volume range: 0dB to -50dB (2dB steps) and -50dB to -70dB (4dB steps).
• Rear Volume range: 0dB to -59dB (-infinity) with 1dB step resolution.
• High S/N ratio achieved by implementing 2-stage configuration of Front and Rear volumes.
• Low power consumption using BiCOMS process technology.
• SSOP-A32 package with separated input/output pin layout to simplify PCB design.

Audio Special Purpose Applications

• Home audio systems
• Mini-component stereo systems
• Micro-audio systems
• Pre-amplifiers for power amplifiers

Audio Special Purpose Procurement Notes

The standard ordering part number often includes the suffix '-E2' (e.g., BD3861FS-E2) indicating tape-and-reel packaging with a quantity of 2000 units. Verify RoHS compliance status as it is marked compliant in current documentation. Check manufacturer lifecycle notices for any end-of-life or last-time-buy announcements.

Audio Special Purpose Selection Notes

Select this component when a compact solution for source selection, tone control, and volume management is required without external equalization components. Ensure the system power supply remains within the 6.5V to 9.5V operating range. Verify that the 2-wire serial interface timing requirements align with the host controller's capabilities.

Audio Special Purpose Part Context

The BD3861FS belongs to ROHM's family of sound processors designed for portable and compact audio equipment. It shares architectural similarities with other models like the BD3883FS but offers specific volume and gain configurations tailored for mini-systems. The SSOP-A32 package is optimized for space-constrained applications.

Audio Special Purpose Replacement Considerations

BD3883FS: Includes surround and rear volume with soft-switching; uses SSOP-A32 package. Verify pin compatibility and control data formats when substituting. Note that the BD3873FS is discontinued and should not be considered for new designs.