AD605BRZ

Overview

The AD605BRZ is a dual-channel, low-noise, linear-in-dB variable gain amplifier (VGA) from Analog Devices. It operates on a single 5 V supply with a bandwidth of 40 MHz and an input noise density of 1.8 nV/√Hz. The device offers a programmable absolute gain range of –14 dB to +34 dB per channel, selectable via external feedback configuration. Each channel draws 18 mA at normal operation, reducing to 1.9 mA in power-down mode when the gain control voltage falls below 50 mV. It features differential inputs, independent output common-mode setting, and a single-polarity gain control interface.

Feature Summary

• Dual independent linear-in-dB channels with DSX-AMP architecture for high-performance wideband variable gain control
• Differential input stage combined with single-ended single-polarity gain control interface for simplified system integration
• Independent output common-mode voltage setting allows flexible signal conditioning without affecting gain characteristics
• Integrated power-down functionality activates automatically when gain control voltage drops below threshold

Applications

• Ultrasonic and sonar time gain control systems
• High-performance automatic gain control (AGC) circuits
• Precision signal measurement instrumentation

Procurement Notes

Verify the specific suffix BRZ indicates the SOIC-16 package variant when sourcing. Confirm RoHS compliance status matches current manufacturing standards. Ensure the revision level of the datasheet aligns with design requirements. Check for any pin-compatible alternatives if lead times are critical. Validate that the operating temperature range meets environmental specifications.

Selection Notes

Select this component when dual-channel linear-in-dB response is required within a single package. Consider the 40 MHz bandwidth limit for high-frequency applications. Evaluate the need for differential inputs versus single-ended options. Assess power consumption constraints given the 18 mA per channel quiescent current. Verify compatibility with the available gain control voltage ranges for the target application.

Part Context

The AD605 series represents Analog Devices' solution for precision variable gain amplification. The BRZ suffix specifically denotes the plastic small-outline integrated circuit (SOIC) package version. This part belongs to the broader family of specialized analog signal processing components designed for test and measurement industries.

Replacement Considerations

The AD605BRZ-R7 is the reel-packaged equivalent of the tube-packed AD605BRZ. Both variants share identical electrical specifications and pinouts. No functional substitution is required between these packaging options.

FAQ

How is the gain range configured?

The gain range is set by connecting a resistor between the FBK and OUT pins or by shorting them. Shorting provides a –14 dB to +34 dB range, while leaving it open provides 0 dB to +48 dB.

What triggers the power-down mode?

Power-down mode activates when the gain control voltage (VGN) drops below 50 mV, reducing the supply current to approximately 1.9 mA.