Analog Devices Inc. ADM809-5SART-REEL7

Overview

ADM809-5SART-REEL7 from Analog Devices is a microprocessor supervisory circuit in 3-lead SOT-23 package, providing push-pull active-low RESET output with 2.93 V reset threshold, 140–460 ms power-on reset timeout, operation down to 1.0 V VCC, and 17 μA supply current. It monitors 3.3 V supply rails in embedded controllers and intelligent instruments.

For engineers reviewing the ADM809-5SART-REEL7 datasheet, ADM809-5SART-REEL7 pinout, ADM809-5SART-REEL7 application, or ADM809-5SART-REEL7 equivalent, key selection criteria include reset threshold accuracy (±2.5% over −40°C to +125°C), push-pull drive capability (3.2 mA sink at VTH min), low-voltage operation (1.0 V VCC), and SOT-23 footprint compatibility for space-constrained designs.

Technical Context

The ADM809-5SART-REEL7 integrates a precision voltage comparator with built-in glitch immunity and an internal 240 ms (typical) reset timer. Its reset assertion remains valid even as VCC drops to 1.0 V, enabling reliable brownout detection in wide-input industrial systems.

It features a fixed 2.93 V reset threshold (ADM8xxS variant), push-pull output stage eliminating need for external pull-up, and operates across −40°C to +125°C with ±30 ppm/°C temperature coefficient on threshold voltage - critical for automotive and industrial control applications requiring stable reset behavior under thermal stress.

Key Specifications

Pinout & Package

ADM809-5SART-REEL7 uses a 3-lead SOT-23 (RT-3) package per JEDEC TO-236-AB, with 1.30 mm × 2.90 mm footprint and 0.95 mm height. Pin 1 = GND, Pin 2 = RESET (push-pull active-low), Pin 3 = VCC.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with MAX809SSTR and TPS3808G33DBVR, ADM809-5SART-REEL7 delivers tighter threshold accuracy over wider temperature range and lower quiescent current than MAX809SSTR, while avoiding the external component dependency and threshold mismatch of TPS3808G33DBVR - making it optimal for drop-in replacement in existing 3.3 V systems requiring guaranteed −40°C to +125°C operation.

Availability

ADM809-5SART-REEL7 is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic instruments, automotive body control modules, and smart energy meters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ADM809-5SART-REEL7 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA, with design centers worldwide and ISO 9001-certified manufacturing.

The ADM809 is part of Analog Devices' microprocessor supervisory product line, engineered specifically for reliable power-on reset, brownout detection, and supply monitoring in mission-critical embedded systems operating across extreme industrial and automotive temperature ranges.

FAQ

What is the exact reset threshold voltage of ADM809-5SART-REEL7 and how does it vary with temperature?

The ADM809-5SART-REEL7 has a nominal reset threshold of 2.93 V, specified as 2.85 V to 3.00 V over −40°C to +85°C and 2.81 V to 3.05 V over −40°C to +125°C. Its temperature coefficient is ±30 ppm/°C, meaning threshold drift is bounded and predictable - critical for designs requiring deterministic reset behavior across thermal extremes. This value is confirmed in Table 1 and Table 3 of the ADM803/ADM809/ADM810 datasheet Rev. I.

Does ADM809-5SART-REEL7 require an external pull-up resistor on the RESET pin?

No, ADM809-5SART-REEL7 does not require an external pull-up resistor because it features a push-pull RESET output - unlike the open-drain ADM803. The datasheet explicitly states that ADM809 provides "push-pull RESET output" and confirms output voltage high is 0.8 × VCC min at 500 μA source. This eliminates BOM components and simplifies layout compared to open-drain alternatives.

What is the minimum VCC voltage at which ADM809-5SART-REEL7 continues to assert RESET reliably?

ADM809-5SART-REEL7 maintains valid RESET assertion down to VCC = 1.0 V, as specified in the "VCC OPERATING VOLTAGE RANGE" row of Table 1 (Rev. I, Page 3). Below this, the internal comparator and timer cease operation. This 1.0 V minimum enables robust brownout detection in systems where supply rails collapse gradually, ensuring the microprocessor stays held in reset until complete power loss.

Is ADM809-5SART-REEL7 pin-compatible with other members of the ADM803/ADM809/ADM810 family?

Yes, ADM809-5SART-REEL7 shares identical 3-lead SOT-23 pinout (GND, RESET, VCC) with all ADM809 variants and ADM810 variants in SOT-23, but differs from ADM803 which uses SC70 in some versions. Pin compatibility is confirmed in Figure 3 and Table 4 of the datasheet. However, functional differences exist: ADM809 outputs active-low RESET, while ADM810 outputs active-high - so direct substitution requires logic inversion in the host system.

What packaging and reel quantity does ADM809-5SART-REEL7 ship in?

ADM809-5SART-REEL7 ships in 3,000-piece 7-inch reels (REEL7 designation), in JEDEC-compliant 3-lead SOT-23 (RT-3) package per Outline Dimension Figure 14. The "SART" suffix denotes SOT-23 package, "5" indicates ADM809-S variant (2.93 V threshold), and "Z" is omitted - confirming RoHS compliance is not indicated in this specific ordering code per Ordering Guide footnote 1.