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-REEL 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-REEL 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-REEL should be validated against the target application's timing and power budget before substitution.
Package Type
High match
Supply Voltage Range
High match
Propagation Delay
Validation required
Input Offset Voltage
Validation required
Parts at a glance
Part B
AD8564AR-REEL
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 9968 PCS
- Package
- SOIC-16
- Series
- Linear - Comparators
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-REEL | 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 | 5.5 ns | Sets the maximum speed at which the comparator output responds to input changes, critical for high-speed timing and signal detection applications. |
| Supply Voltage Range | ±5 V (3 V to ±5 V) | ±5 V (3 V to ±5 V) | Defines the allowable power supply window; both parts support single-supply and dual-supply operation for flexible system integration. |
| Input Offset Voltage (max) | 3 mV | 3 mV | Affects comparison accuracy; lower offset reduces threshold error in precision detection circuits. |
| Supply Current per Comparator | ~6 mA | ~5 mA | Impacts total power consumption; important for battery-powered and thermally constrained designs. |
| Output Type | TTL/CMOS compatible | TTL/CMOS compatible | Determines compatibility with downstream logic families and whether external level shifting is required. |
| Package | 8-Lead SOIC | 14-Lead SOIC | Affects PCB footprint and layout; different pin counts and package sizes impact board space and routing. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +85°C | Defines the environmental envelope for reliable operation in industrial and commercial applications. |
| Input Common-Mode Range | -0.2 V to V+ - 1.5 V | -0.2 V to V+ - 1.5 V | Specifies the valid input voltage window; exceeding it can cause incorrect comparison or device damage. |
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-REEL |
|---|---|---|
| Supplier | - | Analog Devices Inc. |
| 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-REEL?
The AD8561AR is a single high-speed comparator supplied in an 8-lead SOIC package, while the AD8564AR-REEL is a quad high-speed comparator supplied in a 16-lead SOIC package and delivered on tape and reel for automated assembly. The AD8561 offers a single comparator channel, whereas the AD8564 integrates four independent comparators in one package.
Are the AD8561AR and AD8564AR-REEL pin-compatible?
No. The AD8561AR uses an 8-lead SOIC package, and the AD8564AR-REEL uses a 16-lead SOIC package. The pin counts, pin functions, and PCB land patterns differ, so they are not directly interchangeable without a board redesign.
Do both comparators operate from the same supply voltage range?
Both devices are specified for operation from a single +5 V supply as well as from dual ±5 V supplies, consistent with the Analog Devices datasheets for the AD8561 and AD8564 families. Designers should confirm the exact supply range and specifications against the respective datasheet revision before finalizing a design.
How does the propagation delay of the AD8561AR compare with the AD8564AR-REEL?
Both the AD8561 and AD8564 are high-speed comparators with propagation delays in the nanosecond range, typically specified around 7 ns to 9 ns under the datasheet test conditions. Because the exact delay depends on overdrive, load, and supply conditions, the datasheet values for each specific part number should be consulted for critical timing budgets.
Why is the AD8564AR-REEL supplied in tape and reel format?
The "-REEL" suffix indicates the AD8564AR is packaged on tape and reel, which is the standard format for high-volume automated pick-and-place assembly lines. The AD8561AR is typically supplied in tube or standard bulk packaging unless a reel-specific ordering code is selected.
Can the AD8564AR-REEL replace four AD8561AR devices in a design?
Functionally, the AD8564 provides four comparators in one package, which can reduce board space versus four separate AD8561AR devices. However, the AD8564AR-REEL uses a 16-lead SOIC footprint and different pinout, so the PCB layout, thermal considerations, and channel-to-channel matching must be validated against the AD8564 datasheet before substitution.
Are both parts suitable for the same output logic interface?
Both the AD8561 and AD8564 provide complementary output stages suitable for interfacing with digital logic, but the exact output swing, drive capability, and configuration should be verified in the respective datasheets. The AD8564 integrates four comparators, so output loading and crosstalk between channels should be evaluated in the target application.