AD8561ARZ

Overview

The AD8561ARZ is a single ultrafast comparator in an 8-lead narrow SOIC package. It features a typical propagation delay of 7 ns at 5 V supply, with a maximum of 9.8 ns over the industrial temperature range of –40°C to +85°C. The device supports single supply operation from 3 V to 10 V and dual supplies up to ±5 V. Key electrical parameters include a typical input offset voltage of 2.3 mV, a common-mode rejection ratio of 85 dB, and a large signal voltage gain of 3000 V/V. It provides complementary digital outputs and includes a latch function for data retention.

Feature Summary

• Features closely matched rising and falling propagation delays that track over temperature, maintaining output duty cycle matching for clock recovery applications.
• Includes a dedicated latch enable input that retains output data when activated, allowing interface with standard TTL or CMOS logic levels.
• Offers a wide common-mode input voltage range extending from the negative supply rail to within 2.2 V of the positive supply rail.
• Provides complementary open-collector outputs capable of driving significant loads without significantly increasing propagation delay.

Applications

• High speed timing circuits
• Clock recovery and distribution systems
• Line receivers and digital communications
• Phase detectors and high speed sampling

Procurement Notes

Verify the specific ordering suffix to confirm the package type and reel configuration. Ensure the component meets RoHS compliance requirements if applicable to your manufacturing process. Confirm the operating temperature range matches your system specifications before finalizing procurement decisions.

Selection Notes

Select this component when low propagation delay and precise duty cycle preservation are critical. Consider the wider common-mode input range compared to legacy parts like the LT1016. Evaluate power supply constraints as the device operates efficiently on single or dual supplies. Verify that source resistance remains low to prevent performance degradation due to input capacitance interactions.

Part Context

The AD8561 series serves as a high-performance replacement for older comparators such as the LT1016. It maintains pin compatibility while offering improved speed, lower power consumption, and extended input voltage ranges. The device is designed for industrial applications requiring reliable timing and signal processing capabilities across varying environmental conditions.

Replacement Considerations

The AD8561 is a direct pin-compatible upgrade for LT1016 designs. Designers should account for differences in input bias current direction and magnitude, as well as the expanded common-mode input range. Timing adjustments may be necessary due to the faster propagation characteristics of the AD8561 compared to its predecessor.

FAQ

How does the AD8561 handle input signals exceeding the common-mode range?

Signals exceeding the upper limit of the common-mode range (typically 3.0 V on a 5 V supply) may result in slower response times. To maintain optimal performance, input signals should generally remain within the specified common-mode voltage limits.

What is the purpose of the latch input on the AD8561?

The latch input allows the user to retain the current output state regardless of subsequent changes in the input voltages. This feature is useful for capturing transient signals or synchronizing data in high-speed timing applications.

Can the AD8561 operate with dual power supplies?

Yes, the AD8561 supports dual supply operation, typically up to ±5 V. This configuration enables the input stage to utilize the full range between the negative and positive rails, providing flexibility in circuit design.