Analog Devices Inc. ADM13305-4ARZ

Overview

ADM13305-4ARZ from Analog Devices is a dual-voltage supervisor IC with one fixed 2.93 V threshold (SENSE1) and one adjustable 0.6 V reference (SENSE2), operating from 2.7 V to 5.5 V supply, delivering push-pull active-high and active-low RESET outputs, 140 ms minimum reset timeout, and 1.6 sec typical watchdog timeout - used for reliable power-on and fault recovery in microcontroller-based industrial control systems.

For engineers reviewing the ADM13305-4ARZ datasheet, ADM13305-4ARZ pinout, ADM13305-4ARZ application, or ADM13305-4ARZ equivalent, key selection considerations include its dual-supply monitoring architecture, resistor-programmable SENSE2 input, −40°C to +85°C operation, 8-lead SOIC_N package, and integrated manual reset and watchdog timer functions.

Technical Context

The ADM13305-4ARZ implements two independent undervoltage detection paths: SENSE1 uses an internal 2.93 V threshold (±3% over temperature), while SENSE2 accepts an externally set threshold via resistor divider referenced to the 0.6 V internal bandgap. Both inputs feature hysteresis (30 mV at 2.93 V, 0 mV at 0.6 V) and support glitch-immune sensing with ≥30 μs minimum pulse width.

Its on-chip watchdog timer resets the system if the WDI pin fails to toggle within 1.6 sec (typical), and the manual reset (MR) input provides asynchronous reset assertion with 140–280 ms timeout. RESET and RESET outputs are push-pull, valid down to VDD = 1.1 V, and drive ±3 mA at 5.5 V.

Key Specifications

Pinout & Package

ADM13305-4ARZ is housed in an 8-lead narrow-body SOIC package (JEDEC MS-012-AA, R-8), 4.9 mm × 3.9 mm × 1.5 mm, with 1.27 mm lead pitch and RoHS-compliant finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-supply supervision applications.

Compared with MAX6816EPA+ and TPS3808G33DBVR, ADM13305-4ARZ uniquely delivers dual-rail supervision with one fixed and one programmable threshold plus integrated watchdog - making it the only option among the three that supports coordinated reset of heterogeneous power domains in complex embedded systems.

Availability

ADM13305-4ARZ is available at Aetrix Electronics and suitable for industrial PLCs, wireless sensor nodes, notebook embedded controllers, and automated test equipment requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for ADM13305-4ARZ 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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA, with design centers worldwide and broad industrial, automotive, and communications product portfolios.

The ADM13305 family was designed specifically for robust, low-power dual-supply supervision in DSP and microcontroller-based systems - targeting applications demanding guaranteed reset behavior, watchdog safety, and flexible voltage monitoring across diverse power domains.

FAQ

What is the exact SENSE1 and SENSE2 threshold configuration for ADM13305-4ARZ?

The ADM13305-4ARZ has a fixed 2.93 V threshold on SENSE1 (for monitoring 3.3 V supplies) and a 0.6 V internal reference on SENSE2, which is externally programmable via resistor divider to monitor any voltage ≥0.6 V. This configuration is confirmed in the Ordering Guide and Table 2 of the datasheet, with SENSE1 VIT− = 2.90–2.98 V and SENSE2 VIT− = 0.595–0.605 V over temperature.

Does ADM13305-4ARZ require external components to operate as a dual supervisor?

ADM13305-4ARZ requires only a 0.1 μF VDD decoupling capacitor for stable operation. SENSE1 connects directly to the 3.3 V rail. SENSE2 requires an external resistor divider to set the desired threshold voltage - no additional ICs, references, or timing components are needed for full dual-supply supervision and watchdog functionality.

Can the watchdog timer in ADM13305-4ARZ be disabled, and how?

Yes, the watchdog timer in ADM13305-4ARZ can be disabled by leaving the WDI pin unconnected (floating). The datasheet explicitly states "The watchdog timer can be disabled by leaving WDI floating." No pull-up or pull-down resistor is required, and the device operates fully as a dual supervisor without watchdog intervention when WDI is open.

What is the minimum VDD voltage at which ADM13305-4ARZ guarantees correct RESET output state?

ADM13305-4ARZ guarantees correct RESET and RESET output states down to VDD = 1.1 V, as specified in the General Description and Electrical Specifications. This ensures reliable reset assertion during brownout conditions and unregulated power-up sequences - a key differentiator versus supervisors requiring higher minimum VDD.

Is ADM13305-4ARZ pin-compatible with other models in the ADM13305 family?

Yes, ADM13305-4ARZ is pin-compatible with all members of the ADM13305 family (e.g., ADM13305-18ARZ, ADM13305-25ARZ, ADM13305-33ARZ, ADM13305-5ARZ), sharing identical 8-lead SOIC_N (R-8) pinout, electrical characteristics, and functional block diagram - enabling drop-in replacement across threshold variants without PCB redesign.