Part A
AD8561AR
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 4375 PCS
- Package
- SOIC-8
- Series
- Linear - Comparators
Replacement verdict
Compatible functional replacement candidate
The AD8561AR and AD8564AR are both single high-speed voltage comparators from Analog Devices in the same 8-lead SOIC package, sharing a comparable supply range and pin function. The AD8564AR offers a faster propagation delay and higher toggle rate, making it a viable functional upgrade candidate, though the tighter input offset voltage and higher supply current of the AD8564AR should be validated against the target application's timing, accuracy, and power budget before substitution.
Package Type
High match
Supply Voltage Range
High match
Propagation Delay
Validation required
Input Offset Voltage
Validation required
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD8561AR | AD8564AR | Why it matters |
|---|---|---|---|
| Number of Comparators | 1 | 4 | Determines how many independent comparison channels are available in a single package, directly affecting circuit density and channel count. |
| Propagation Delay | 7 ns (typ) | 7 ns (typ) | Sets the maximum speed at which the comparator can respond to input changes; critical for high-speed timing and signal detection applications. |
| Supply Voltage Range | ±5 V (dual) or 5 V to 10 V | ±5 V (dual) or 5 V to 10 V | Defines the operating voltage window; must match the system supply rails for proper operation and signal swing compatibility. |
| Input Offset Voltage | 0.5 mV (typ) | 0.5 mV (typ) | Affects comparison accuracy; lower offset reduces threshold error and improves precision in sensitive detection circuits. |
| Input Bias Current | 1 µA (typ) | 1 µA (typ) | Influences input loading and offset error, especially with high-impedance sources; lower bias current improves accuracy. |
| Output Type | TTL/CMOS compatible | TTL/CMOS compatible | Determines compatibility with downstream logic families and whether external level shifting or pull-ups are required. |
| Package | 8-Lead SOIC | 14-Lead SOIC | Affects PCB footprint, layout, and pin count; a different package requires board redesign and cannot be drop-in substituted. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Ensures reliable operation across the intended environmental conditions; must meet the application's thermal requirements. |
| Supply Current per Comparator | ~6 mA (typ) | ~6 mA (typ) | Impacts total power consumption; important for power-sensitive and battery-operated designs. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AD8561AR | AD8564AR |
|---|---|---|
| Part Status | Obsolete | Obsolete |
| Type | General Purpose | General Purpose |
| Number of Elements | 1 | 4 |
| Output Type | CMOS, Complementary, TTL | CMOS, TTL |
| Voltage - Input Offset (Max) | 7mV @ 5V | 7mV @ 5V |
| Current - Input Bias(Max) | 6µA @ 5V | 4µA @ 5V |
| Current - Quiescent (Max) | 6mA, 3.3mA, 5.5mA | 14mA, 14mA, 7mA |
| CMRRPSRR(Typ) | 85dB CMRR, 65dB PSRR | 85dB CMRR, 80dB PSRR |
| Propagation Delay(Max) | 9.8ns | 9.8ns |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
| Voltage - Supply, Single/Dual (±) | 3V ~ 10V, ±1.5V ~ 5V | - |
Frequently asked questions
What are the primary differences between the AD8561AR and AD8564AR?
The AD8561AR is a single high-speed comparator, while the AD8564AR is a quad high-speed comparator. Both are fabricated on Analog Devices' proprietary XFCB process and feature 7 ns propagation delay, but they differ in channel count, package pinout, and power consumption per device.
Are the AD8561AR and AD8564AR pin-compatible?
No. The AD8561AR is offered in an 8-lead SOIC package, whereas the AD8564AR is offered in a 16-lead SOIC package. The pin counts, pin functions, and PCB land patterns differ, so they are not drop-in replacements for one another.
Do both comparators have the same propagation delay?
Yes. Both the AD8561AR and AD8564AR are specified with a typical propagation delay of 7 ns, making them suitable for high-speed signal processing and timing applications.
What is the supply voltage range for the AD8561AR and AD8564AR?
Both devices operate from a single supply of 3 V to 10 V or from dual supplies of ±1.5 V to ±5 V, as specified in the Analog Devices datasheets.
How does power consumption compare between the AD8561AR and AD8564AR?
The AD8561AR (single comparator) typically draws about 6.5 mA per device, while the AD8564AR (quad comparator) typically draws about 26 mA per device, reflecting the four comparator channels integrated in the AD8564AR.
Which device should be selected for a multi-channel comparator design?
The AD8564AR is the appropriate choice for multi-channel designs because it integrates four independent comparators in a single 16-lead SOIC package, reducing board space and component count compared with using four AD8561AR devices.
Are the AD8561AR and AD8564AR available in the same operating temperature range?
Both the AD8561AR and AD8564AR are specified for the industrial temperature range of −40°C to +85°C, as stated in the Analog Devices datasheets.