BD9251FV-E2

Overview

The BD9251FV-E2 is a single-chip amplifier IC designed for pyroelectric infrared sensors in human body detection applications. It integrates an amplifier, comparator, voltage regulator, and moving detector circuitry to reduce standby power requirements and minimize external component count. The device operates within a supply voltage range of 2.97 V to 6.0 V, with a typical supply current of 300 uA at no load. Key electrical characteristics include a closed-loop gain of 46 dB, a unity gain frequency of 1 MHz, and an input offset voltage of up to 10 mV. It supports an operating temperature range from -30°C to +75°C and is housed in an SSOP-B14 package.

Feature Summary

• Integrates dual-stage amplification and comparator functions specifically optimized for pyroelectric sensor signals.
• Includes a built-in voltage regulator and dedicated drain output to power the connected infrared sensor directly.
• Features a moving detection output (T_OUT) that enables direction sensing when used with dual-element sensors.

Applications

• Security systems
• Sensor lights and lighting control
• Web cameras
• Air conditioners and ventilation fans

Procurement Notes

Verify the specific ordering suffix E2 corresponds to the embossed tape and reel packaging format before procurement. Confirm that the SSOP-B14 package dimensions align with the target PCB footprint. Ensure the design accounts for the recommended minimum order quantity associated with the reel packaging specification.

Selection Notes

Select this component for designs requiring low standby power consumption in human presence detection circuits. The integrated amplifier and comparator simplify the signal chain compared to discrete solutions. Verify that the required supply voltage remains within the 2.97 V to 6.0 V operational window for stable performance across the specified temperature range.

Part Context

The BD9251FV belongs to ROHM's series of interface ICs tailored for sensor applications. This specific model consolidates multiple analog stages into one package to facilitate space-saving designs. It serves as a specialized solution for motion detection logic, distinguishing itself from general-purpose operational amplifiers by including dedicated outputs for sensor biasing and digital detection flags.

Replacement Considerations

No public confirmed substitute part numbers are available in the provided documentation. Designers should consult ROHM sales representatives for potential alternative components if this part becomes unavailable.

FAQ

How does the T_OUT pin function?

The T_OUT pin provides a moving detection output. When used with a dual-type pyroelectric sensor, checking the switch of the T_OUT signal while D_OUT is high allows the system to detect the direction of movement.

What is the purpose of the DRAIN pin?

The DRAIN pin serves as the power supply output for the connected pyroelectric infrared sensor. It maintains a typical voltage of 2.3 V when the supply voltage is above 2.97 V and can source up to 100 µA.

What is the maximum supply voltage allowed?

The absolute maximum rating for the supply voltage (VDD) is 7.0 V. However, the recommended operating supply voltage range is between 2.97 V and 6.0 V.