Analog Devices Inc./Maxim Integrated MAX6351RVUT

Overview

MAX6351RVUT from Maxim Integrated is a dual-voltage microprocessor supervisory IC with precision reset threshold monitoring for VCC1 and VCC2, featuring two active-low push-pull reset outputs (RST1 referenced to VCC1, RST2 referenced to VCC2), 20µA supply current, 100ms minimum power-on reset pulse width, and guaranteed RESET validity down to VCC1 ≥ 1.0V or VCC2 ≥ 1.0V. It is designed for multivoltage systems requiring reliable power sequencing and fault detection in portable and industrial embedded applications.

For engineers reviewing the MAX6351RVUT datasheet, MAX6351RVUT pinout, MAX6351RVUT application, or MAX6351RVUT equivalent, this device delivers verified dual-supply monitoring with factory-set thresholds (VTH1 = 2.63V, VTH2 = 1.58V), SOT23-6 packaging, -40°C to +85°C operation, and no external components required for dual-rail supervision.

Technical Context

The MAX6351RVUT implements independent voltage comparators for VCC1 and VCC2, asserting both RST1 and RST2 when either supply drops below its respective threshold. Its reset logic guarantees output validity as long as at least one supply remains ≥1.0V, enabling robust brownout recovery in asymmetric power-down scenarios.

It includes a debounced TTL/CMOS-compatible manual reset input (MR), supports transient immunity up to 250µs at 100mV overdrive, and features internal hysteresis (VTH/500) to prevent chatter during threshold crossings. The device operates without external timing components and requires no pull-up resistors for its push-pull outputs.

Key Specifications

Pinout & Package

MAX6351RVUT is housed in a 6-pin SOT23-6 package with gull-wing leads, 1.27mm pitch, and JEDEC MO-178AC compliant footprint. Thermal resistance θ_JA = 115°C/W; maximum power dissipation = 695mW at +70°C.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-voltage supervisory applications.

Compared with MAX6351MTUT, MAX6351RVUT provides tighter threshold matching for modern low-voltage rails (2.63V/1.58V vs. 4.38V/3.08V), while TPS3808G33DBVR reduces power consumption but sacrifices dual-rail coordination and increases board space due to discrete implementation.

Availability

MAX6351RVUT is available at Aetrix Electronics and suitable for portable medical devices, industrial PLC I/O modules, automotive body control units, network edge routers, and battery-powered instrumentation requiring stable component supply across extended temperature ranges.

Supply support for MAX6351RVUT 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

Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, and communications applications.

The MAX6351–MAX6360 family was engineered to replace discrete resistor-divider + comparator solutions in multivoltage embedded systems, delivering integrated dual/triple-supply supervision with factory-trimmed accuracy and minimal external components.

FAQ

What are the exact factory-set reset thresholds for MAX6351RVUT?

The MAX6351RVUT has precisely trimmed reset thresholds: VTH1 = 2.63V (±2.7%) for VCC1 and VTH2 = 1.58V (±2.7%) for VCC2, validated across -40°C to +85°C. These values correspond to the "RV" suffix in the Voltage Threshold Levels table and are laser-trimmed at wafer test-no external calibration is needed. The MAX6351RVUT uses these fixed thresholds to supervise common low-voltage rails like +2.5V and +1.5V without resistor dividers.

Does MAX6351RVUT support operation when only one supply is present?

Yes, MAX6351RVUT guarantees valid reset outputs as long as either VCC1 ≥ 1.0V or VCC2 ≥ 1.0V, per Absolute Maximum Ratings and Electrical Characteristics tables. This allows safe operation during asymmetric power-up sequences-for example, if VCC2 ramps first, RST2 remains functional while VCC1 is still at 0V. The MAX6351RVUT's internal biasing ensures correct logic states even with single-supply biasing, making it suitable for hot-swap and partial-power scenarios.

What is the reset pulse width specification for MAX6351RVUT, and is it temperature-stable?

The MAX6351RVUT provides a minimum power-on reset pulse width of 100ms, with typical values of 180ms and maximum of 280ms over -40°C to +85°C. This parameter is fully guaranteed across temperature and supply voltage (VCC1/VCC2 = 1.2V to 5.5V) and does not require external timing components. The MAX6351RVUT achieves this stability through on-chip RC timing with <20ppm/°C tempco, ensuring consistent µP initialization timing in varying environmental conditions.

Can MAX6351RVUT be used with bidirectional µP reset pins?

Yes, but requires external series resistance: connect a 4.7kΩ resistor between RST1 or RST2 and the µP's bidirectional reset I/O port to prevent contention during µP-driven reset assertion. This configuration is explicitly validated in the Applications Information section of the MAX6351RVUT datasheet (Figure 5). The MAX6351RVUT's push-pull outputs drive strongly low but tolerate limited current sink from the µP, and the resistor ensures safe voltage division during bidirectional transitions.

Is MAX6351RVUT RoHS-compliant and available in lead-free packaging?

Yes, MAX6351RVUT is offered in lead-free packaging; specify "+T" instead of "-T" in the order code (e.g., MAX6351RVUT+T) to receive RoHS-compliant, matte-tin-plated SOT23-6 devices. Both leaded and lead-free versions meet JEDEC J-STD-020 moisture sensitivity level 1 (MSL1) and are qualified for reflow soldering per IPC/JEDEC J-STD-020. The MAX6351RVUT's lead-free variant maintains identical electrical performance and thermal characteristics as the leaded version.