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-REEL7 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-REEL7 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-REEL7 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-REEL7
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 2222 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-REEL7 | Why it matters |
|---|---|---|---|
| Number of Comparators | 1 | 4 | Determines how many independent comparison channels are available in a single package; a quad device can replace four singles but not vice versa. |
| 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 pulse applications. |
| Supply Voltage Range | ±5 V (dual) or 5 V to 10 V single-supply | ±5 V (dual) or 5 V to 10 V single-supply | Defines the allowable power supply window; must match the system rail to ensure correct operation and output logic levels. |
| Input Offset Voltage | 3 mV (max) | 3 mV (max) | Affects comparison accuracy; lower offset reduces threshold error in precision detection circuits. |
| Output Type | TTL/CMOS compatible | TTL/CMOS compatible | Determines compatibility with downstream logic families; must match the receiving logic thresholds. |
| Package | 8-lead SOIC | 14-lead SOIC | Footprint and pin count must match the PCB layout; different packages are not drop-in compatible. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +85°C | Ensures reliable operation across the intended environmental conditions of the application. |
| Supply Current per Comparator | ~6 mA (typ) | ~6 mA (typ) | Impacts total power budget; higher current draw affects thermal design and battery life. |
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-REEL7 |
|---|---|---|
| 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 key differences between the AD8561AR and AD8564AR-REEL7?
The AD8561AR is a single ultrafast comparator in an 8-lead SOIC package, while the AD8564AR-REEL7 is a quad ultrafast comparator in a 16-lead SOIC package supplied on tape and reel. The AD8561 offers one comparator per package, whereas the AD8564 integrates four independent comparators, making it suitable for higher-density designs. Both are fabricated on the same high-speed complementary bipolar process and share similar propagation delay characteristics.
What is the propagation delay of the AD8561AR and AD8564AR-REEL7?
Both the AD8561AR and AD8564AR-REEL7 feature a typical propagation delay of 7 ns. This fast response makes them suitable for high-speed signal processing, timing, and threshold detection applications.
Are the AD8561AR and AD8564AR-REEL7 pin-compatible?
No. The AD8561AR is an 8-lead SOIC single comparator, while the AD8564AR-REEL7 is a 16-lead SOIC quad comparator. They have different pin counts and pinouts, so they are not directly interchangeable on the same PCB footprint.
What supply voltage range do the AD8561AR and AD8564AR-REEL7 support?
Both devices operate from a single supply of 3 V to 10 V or from dual supplies of ±1.5 V to ±5 V. This flexibility supports use in both 5 V logic systems and split-supply analog designs.
What is the difference in packaging between the AD8561AR and AD8564AR-REEL7?
The AD8561AR is supplied in an 8-lead SOIC tube or tray format, while the AD8564AR-REEL7 is supplied in a 16-lead SOIC on a 7-inch tape and reel. The REEL7 suffix indicates tape-and-reel packaging intended for automated pick-and-place assembly.
Do the AD8561AR and AD8564AR-REEL7 have the same input offset voltage specification?
Both devices specify a typical input offset voltage of 0.7 mV and a maximum of 3 mV at 25°C. The matching offset specifications allow either part to be used in precision threshold detection applications within their respective channel counts.
Can the AD8564AR-REEL7 replace the AD8561AR in an existing design?
Not directly. Although both share similar electrical performance, the AD8564AR-REEL7 is a quad device in a 16-lead package, while the AD8561AR is a single device in an 8-lead package. A replacement requires a PCB redesign to accommodate the different footprint, pinout, and additional comparator channels.
What output configuration do the AD8561AR and AD8564AR-REEL7 provide?
Both comparators feature complementary TTL/CMOS-compatible outputs. The AD8561AR provides one complementary output pair, while the AD8564AR-REEL7 provides four independent complementary output pairs, one per comparator channel.