Analog Devices Inc./Maxim Integrated MAX6392KA17+

Overview

MAX6392KA17+ from Maxim Integrated is a dual-voltage microprocessor supervisory circuit with sequenced reset outputs, designed for multi-rail systems requiring controlled power-up/down sequencing. It monitors VCC (master supply) at 1.67V threshold and RESET IN2 (secondary supply) down to 625mV via external resistor divider, asserts active-low push-pull RESET1 and open-drain RESET2 with guaranteed reset validity down to VCC = 1V, and includes active-low manual reset (MR) input - used in industrial controllers and multivoltage servers.

For engineers reviewing the MAX6392KA17+ datasheet, MAX6392KA17+ pinout, MAX6392KA17+ application, or MAX6392KA17+ equivalent, key selection criteria include factory-fixed 1.67V VCC reset threshold, MR-triggered synchronized deassertion timing, CSRT-configurable RESET2 timeout (140ms min or capacitor-adjustable), and guaranteed operation at VCC ≥ 1.0V across –40°C to +85°C.

Technical Context

The MAX6392KA17+ implements two independent voltage monitoring paths: VCC is compared against a factory-trimmed 1.67V bandgap reference to control RESET1 (push-pull, active-low), while RESET IN2 is compared against a fixed 625mV internal reference to condition RESET2 assertion. RESET2 deasserts only after both VCC exceeds 1.67V *and* RESET IN2 exceeds 625mV, with timing governed by either internal counter (CSRT tied to VCC) or external capacitor ramp (CSRT to ground).

RESET1 and RESET2 are sequenced: during power-up, RESET1 deasserts first (140ms min after VCC rise), then RESET2 follows after its own timeout; during power-down, RESET2 asserts before RESET1. MR forces simultaneous assertion of both outputs with 10µs skew (tMR1 − tMR2 ≤ 10µs), and internal 47kΩ pullup ensures defined MR logic level when unconnected.

Key Specifications

Pinout & Package

MAX6392KA17+ is housed in an 8-pin SOT23-8 package (JEDEC MO-178 compliant, 1.95mm × 2.80mm footprint, 1.30mm height), optimized for space-constrained industrial and embedded PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6392KA22+ and TPS3808G18DBVR, the MAX6392KA17+ uniquely delivers 1.67V precision VCC monitoring combined with configurable dual-output sequencing - making it irreplaceable in 1.8V/1.2V or 3.3V/1.8V systems requiring strict power-order enforcement.

Availability

MAX6392KA17+ is available at Aetrix Electronics and suitable for industrial controllers, servers/workstations, and multivoltage embedded systems requiring stable component supply, long-term lifecycle support, and guaranteed lead-free compliance.

Supply support for MAX6392KA17+ 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, communications, and computing applications.

The MAX6391/MAX6392 product line was designed specifically for dual-rail microprocessor systems needing deterministic, sequenced reset generation - eliminating discrete supervision circuits while maintaining timing integrity across voltage domains.

FAQ

What is the factory-trimmed VCC reset threshold voltage for MAX6392KA17+?

The MAX6392KA17+ features a factory-trimmed VCC reset threshold of 1.67V (nominal), with guaranteed tolerance of ±5% over the full –40°C to +85°C operating temperature range. This value is laser-trimmed during production and documented in the Selector Guide and Electrical Characteristics table. The 1.67V threshold makes MAX6392KA17+ suitable for monitoring 1.8V supply rails with appropriate design margin.

Does MAX6392KA17+ support manual reset functionality, and how is it implemented?

Yes, MAX6392KA17+ includes an active-low manual reset (MR) input on Pin 8. It features an internal 47kΩ pullup resistor to VCC, requiring only a simple switch-to-ground interface. When MR is pulled low, both RESET1 (push-pull) and RESET2 (open-drain) assert simultaneously with ≤10µs skew. The MAX6392KA17+ remains in reset for the full RESET1 and RESET2 timeout periods after MR is released.

How is the RESET2 timeout period configured on MAX6392KA17+?

The RESET2 timeout on MAX6392KA17+ is configured via the CSRT pin (Pin 3). Connecting CSRT to VCC selects a fixed 140ms minimum timeout. Connecting CSRT to an external capacitor (CCSRT) to ground enables user-adjustable timing per the formula tRP2 ≈ 2.08 × 10⁶ × CCSRT seconds. For example, a 1500pF capacitor yields ~3.1ms, while larger values scale linearly - giving designers precise control over secondary reset sequencing.

Can MAX6392KA17+ operate reliably at VCC = 1.2V, and what is the lowest valid VCC for reset assertion?

Yes, MAX6392KA17+ is fully specified to operate with VCC as low as 1.2V, and its reset outputs remain guaranteed valid down to VCC = 1.0V. This ensures deterministic reset assertion during deep brownout events where other supervisors may fail or produce glitches. The 1.0V lower limit is tested and guaranteed across temperature, making MAX6392KA17+ suitable for ultra-low-voltage industrial and battery-backed systems.

What package type and footprint does MAX6392KA17+ use, and are there layout considerations for RESET2 pullup?

MAX6392KA17+ uses an 8-pin SOT23-8 package (JEDEC MO-178, 1.95mm × 2.80mm). For RESET2 (Pin 5), the internal 47kΩ pullup resistor (R2, Pin 6) must be connected to the target VOH rail (e.g., 3.3V or 5V) - not VCC - to ensure correct logic-high level when RESET2 is inactive. This allows independent voltage translation without external components, but requires routing R2 to the appropriate supply domain.