Part A
ADM705AR
ADI公司
- Lifecycle
- Active
- Stock
- 2558 件
- Package
- SOIC-8
- Series
- PMIC-首長
Replacement verdict
Compatible functional replacement candidate
The ADM705AR and ADM706RAR are both supervisory circuits from the same manufacturer family, sharing a common SOIC-8 footprint and similar functional architecture, making them a viable functional replacement candidate. However, the ADM706RAR offers a higher reset threshold voltage tailored for 3.3V systems, while the ADM705AR targets 5V rails, so the replacement is only appropriate when the threshold voltage and reset polarity requirements of the target design are validated against the actual system supply.
Reset Threshold Voltage
Validation required
Package Type
High match
Supply Voltage Range
High match
Reset Output Configuration
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 | ADM705AR | ADM706RAR | Why it matters |
|---|---|---|---|
| Reset Threshold Voltage (typ) | 4.65 V | 2.63 V | Determines the supply voltage level at which the supervisor asserts reset; must match the monitored rail's nominal voltage for correct operation. |
| Monitored Supply Voltage Range | 4.75 V to 5.5 V (5 V systems) | 2.85 V to 5.5 V (3 V/3.3 V systems) | Defines which logic supply the device can supervise; a mismatch means the supervisor will not correctly monitor the target rail. |
| Reset Output Type | Active-low push-pull | Active-low push-pull | Push-pull outputs drive the reset line directly without an external pull-up, simplifying interfacing to the processor reset pin. |
| Manual Reset Input | Yes | Yes | Allows an external push-button or logic signal to force a system reset, useful for debug and user-initiated resets. |
| Watchdog Timer | Yes (1.6 s typ) | Yes (1.6 s typ) | Monitors processor activity and asserts reset if the software fails to strobe within the timeout, improving system reliability. |
| Reset Timeout Period (typ) | 200 ms | 200 ms | Holds reset asserted long enough for the supply and processor clock to stabilize before code execution begins. |
| Supply Current (typ) | 190 µA | 190 µA | Low quiescent current is important for always-on supervisory functions and battery-backed or low-power designs. |
| Package | 8-lead SOIC (R) | 8-lead SOIC (R) | Identical footprint and pinout allow drop-in board replacement without layout changes. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Confirms both parts are rated for industrial temperature environments, ensuring reliable operation across the same conditions. |
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 | ADM705AR | ADM706RAR |
|---|---|---|
| Part Status | Obsolete | Obsolete |
| Type | Simple Reset/Power-On Reset | Simple Reset/Power-On Reset |
| Number of Voltages Monitored | 1 | 1 |
| Voltage - Threshold | 4.65V | 2.63V |
| Output | Push-Pull, Totem Pole | Push-Pull, Totem Pole |
| Reset | Active Low | Active Low |
| Reset Timeout | 160ms Minimum | 160ms Minimum |
| Operating Temperature | -40°C ~ 85°C (TA) | -40°C ~ 85°C (TA) |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the primary differences between the ADM705AR and ADM706RAR?
Both are Analog Devices microprocessor supervisory circuits in 8-lead SOIC packages, but they differ in reset threshold voltage and reset output configuration. The ADM705AR has a 4.65 V reset threshold with an active-low push-pull RESET output, while the ADM706RAR has a 2.63 V reset threshold with an active-low push-pull RESET output. The ADM705 is intended for 5 V systems, and the ADM706R is intended for 3 V/3.3 V systems.
Can the ADM705AR and ADM706RAR be substituted for each other directly?
No. The ADM705AR monitors a 4.65 V threshold suitable for 5 V rails, whereas the ADM706RAR monitors a 2.63 V threshold suitable for 3 V/3.3 V rails. Substituting one for the other would result in incorrect reset assertion for the target supply voltage, so replacement requires design validation against the respective datasheet.
What supply voltage range does each device support?
The ADM705AR operates from a supply voltage of 4.75 V to 5.5 V, targeting 5 V systems. The ADM706RAR operates from 2.7 V to 5.5 V, targeting 3 V/3.3 V systems. Both specifications are per the Analog Devices ADM705/ADM706 datasheet.
What reset output type do the ADM705AR and ADM706RAR provide?
Both the ADM705AR and ADM706RAR provide an active-low RESET output with a push-pull (totem-pole) configuration. This differs from the open-drain RESET output options available in other variants of the ADM705/ADM706 family.
Do the ADM705AR and ADM706RAR include a watchdog timer and manual reset input?
Yes. Both devices integrate a watchdog timer and a manual reset (MR) input in addition to the power-fail comparator and reset generator. The watchdog timeout and manual reset functionality are common to the ADM705/ADM706 family per the Analog Devices datasheet.
What package do the ADM705AR and ADM706RAR use?
Both the ADM705AR and ADM706RAR are supplied in an 8-lead SOIC (Small Outline Integrated Circuit) package, denoted by the "R" suffix in the ordering code. The package and pinout are identical between the two variants.
What is the purpose of the power-fail comparator on these devices?
The power-fail comparator provides an early warning of an impending power failure by monitoring an unregulated supply or other voltage via the PFI input and asserting the PFO output when the monitored voltage falls below the 1.25 V internal reference threshold. This allows the system to perform orderly shutdown or data protection before the regulated rail drops below the reset threshold.
Are the ADM705AR and ADM706RAR suitable for 3.3 V and 5 V mixed-system designs?
Each device should be selected according to the rail it monitors: the ADM705AR for 5 V rails (4.65 V threshold) and the ADM706RAR for 3 V/3.3 V rails (2.63 V threshold). In a mixed 5 V and 3.3 V system, the appropriate variant must be chosen per rail to ensure correct reset assertion and release.