Analog Devices Inc./Maxim Integrated MAX6301CSA

Overview

MAX6301CSA from Maxim Integrated is an adjustable low-power microprocessor supervisory circuit with active-low open-drain reset output, 4µA supply current, 1.22V internal reference, and user-configurable reset/watchdog timeout via external capacitors. It monitors VCC or other supply rails in battery-powered embedded controllers and portable medical instruments.

For engineers reviewing the MAX6301CSA datasheet, MAX6301CSA pinout, MAX6301CSA application, or MAX6301CSA equivalent, key selection criteria include its guaranteed RESET assertion down to VCC = 1V, 500× watchdog timeout multiplier via WDS pin, power-supply transient immunity up to 50µs at 100mV overdrive, and SO-8 package compatibility with space-constrained PCB layouts.

Technical Context

The MAX6301CSA implements a precision bandgap-based voltage reference (1.22V ±25mV) feeding a high-impedance comparator that monitors RESET IN. Its reset timeout (tRP) and watchdog timeout (tWD) are set by external capacitors on SRT and SWT pins, each sourcing a stable 500nA timing current.

Watchdog operation supports two modes: normal (WDS = GND, tWD in ms) and extended (WDS = VCC, tWD × 500 in seconds). The open-drain RESET output is compatible with bidirectional µP reset pins and requires an external pull-up; reset deassertion occurs after tRP following VIN crossing VRST.

Key Specifications

Pinout & Package

MAX6301CSA is housed in an 8-pin SO (Small Outline) package per JEDEC MS-012, with 1.27mm pitch and gull-wing leads. Thermal performance: 471mW max power dissipation at +70°C, derating 5.88mW/°C above ambient.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6301CSA, MAX6303CSA eliminates external pull-up dependency but loses open-drain flexibility, while TPS3808G01DBVR reduces power and cost at the expense of adjustability - making MAX6301CSA optimal for designs requiring both precision threshold setting and dual-mode watchdog control.

Availability

MAX6301CSA is available at Aetrix Electronics and suitable for medical portable monitors, industrial embedded controllers, and handheld test instruments requiring stable component supply, RoHS-compliant packaging, and long-term production continuity.

Supply support for MAX6301CSA 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) designs precision analog and mixed-signal ICs for power management, sensing, and interface applications in industrial, medical, and communications systems.

The MAX6301–MAX6304 family delivers configurable µP supervision with ultra-low quiescent current and robust noise immunity - engineered specifically for battery-powered and mission-critical embedded systems demanding reliable power-on, brownout, and software-fault recovery.

FAQ

What is the guaranteed minimum VCC level at which MAX6301CSA asserts RESET?

The MAX6301CSA guarantees RESET assertion at or above VCC = 1V, ensuring reliable reset initiation even during deep brownout conditions. This behavior is explicitly specified for the MAX6301 and MAX6303 variants in the Electrical Characteristics table under "Guaranteed RESET Asserted At or Above VCC = 1V". Below 1V, output drive capability declines, but the device remains functional down to VCC = 0V with appropriate external biasing.

How does the WDS pin affect watchdog timeout in MAX6301CSA?

In MAX6301CSA, the WDS pin selects between two watchdog modes: when pulled to GND, it enables normal mode with millisecond-scale timeout (e.g., 2.8–5.2ms with 1500pF); when pulled to VCC, it activates extended mode, multiplying the base timeout by 500 (e.g., 1.4–2.6s with same capacitor). A state change on WDS immediately resets the watchdog counter, enabling dynamic mode switching during µP operation.

Can MAX6301CSA monitor voltages other than VCC?

Yes, MAX6301CSA can monitor any DC voltage rail by connecting it to the RESET IN pin through an external resistor divider. The internal 1.22V reference compares against the divided voltage, so VRST = 1.22 × (R1 + R2)/R2. This allows precise brownout detection on 1.8V, 2.5V, 3.3V, or custom rails - confirmed in the "Monitoring Voltages Other than VCC" section and Figure 4 of the datasheet.

What capacitor types are recommended for SRT and SWT on MAX6301CSA?

Ceramic capacitors are recommended for both SRT and SWT pins due to their low leakage (<10nA) and stability. The datasheet explicitly states CSRT and CSWT must be low-leakage types to prevent timing errors, as the internal 500nA current source is highly sensitive to leakage paths. X7R or C0G dielectrics are preferred; electrolytic or high-leakage film capacitors must be avoided.

Is MAX6301CSA pin-compatible with other members of the MAX6301–MAX6304 family?

Yes, MAX6301CSA shares identical pinout and package (8-pin SO) with MAX6302CSA, MAX6303CSA, and MAX6304CSA - all follow the same top-view pin configuration shown in the "Pin Configuration" diagram. However, output type differs: MAX6301CSA has open-drain active-low RESET, while MAX6303CSA uses push-pull active-low, requiring design review before substitution.