BA3835F-E2

Overview

The BA3835F-E2 is a silicon monolithic integrated circuit designed as a band-pass filter for spectrum analyzers in car audio systems. It supports five frequency bands: 105Hz, 340Hz, 1kHz, 3.4kHz, and 10.5kHz. The device operates on a 5V microcomputer power supply with a recommended voltage range of 4.5V to 6.5V. Key electrical parameters include a typical circuit current of 8.5mA, an input impedance of 100kΩ, and a common-mode rejection ratio of 50dB at 1kHz. The maximum output level is typically 4.8V, and the package type is SOP18.

Feature Summary

• Built-in five-band pass filter specifically configured for car audio spectrum analyzer applications.
• Designed for direct operation with standard 5V microcomputer power supplies.
• Features logic-controlled output selection via A, B, C, and SEL pins for precise band switching.

Applications

• Spectrum analyzer circuits for automotive audio systems
• Five-band equalizer visualization displays
• Audio signal processing equipment requiring specific frequency band isolation

Procurement Notes

Verify the exact ordering suffix against the manufacturer's official documentation to ensure compatibility with required packaging or temperature grades. Confirm that the component status aligns with long-term availability requirements for the intended production volume. Cross-reference pin assignments with the latest datasheet revision to prevent mounting errors during assembly.

Selection Notes

Select this component when a dedicated five-band filter solution for 5V automotive audio systems is required. Ensure the application environment stays within the -25°C to +75°C operating temperature range. Verify that the load connected to the AOUT pin has sufficient input impedance to maintain the specified output levels without significant voltage drop.

Part Context

The BA3835F-E2 belongs to ROHM's specialized analog IC lineup for consumer electronics, specifically targeting automotive audio enhancements. It integrates multiple band-pass filters into a single SOP18 package, reducing board space compared to discrete solutions. This integration supports compact designs in modern vehicle head units and dashboard displays.

Replacement Considerations

No public confirmed substitute part numbers are available in the provided documentation. Any replacement must be evaluated based on identical pinout, voltage ratings, and frequency response characteristics. Consult ROHM sales representatives for potential obsolescence management or alternative recommendations.

FAQ

How is the frequency characteristic of the BA3835F determined?

The frequency characteristics are determined by the resistor connected between the RREF terminal and GND. For standard specifications, a 100kΩ resistor is used. Using a variable resistor allows for adjustment, though all bands will shift together.

What is the impact of the output selection cycle time on performance?

The output offset voltage varies with the cycle time (Ts). If Ts is less than 50ms, the offset voltage increases due to transient characteristics of the peak hold circuit. A longer cycle time helps minimize this offset.

Can the BA3835F be used in strong magnetic fields?

No, the device is not designed for radiation resistance or strong magnetic field environments. Operation in such conditions may cause malfunction, so adequate evaluation is necessary if such exposure is possible.