Monolithic Power Systems Inc. MP6400DJ-12-LF-Z

Overview

MP6400DJ-12-LF-Z from Monolithic Power Systems is a low-quiescent-current (1.6µA typ), programmable-delay supervisory circuit in TSOT23-6 package, designed to monitor 1.2V system rails with ±1% threshold accuracy and assert an open-drain RESET signal upon undervoltage or manual reset assertion. It supports battery-powered microcontroller systems requiring guaranteed reset validity down to VCC = 0.8V.

For engineers reviewing the MP6400DJ-12-LF-Z datasheet, MP6400DJ-12-LF-Z pinout, MP6400DJ-12-LF-Z application, or MP6400DJ-12-LF-Z equivalent, key selection criteria include factory-set 1.12V SENSE threshold, user-selectable delay modes (24ms float, 380ms VCC-tied, or 2.1ms–10s capacitor-programmed), and MR input with 90kΩ internal pull-up for multi-rail coordination.

Technical Context

The MP6400DJ-12-LF-Z implements a precision voltage comparator with hysteresis (1.5–3.5% of VIT) and a 140nA current source for CDELAY capacitor charging, enabling accurate timing from 2.1ms to 10s. Its SENSE input accepts voltages ≥0.4V and tolerates short negative transients up to 17.5µs at 5% overdrive.

RESET output is open-drain with VOL ≤0.4V at IOL = 1.0mA and supports rail-to-rail pull-up (up to 6V), while MR input operates with VIH ≥0.7VCC and VIL ≤0.25VCC, internally biased via 90kΩ resistor to VCC - eliminating external biasing in most applications.

Key Specifications

Pinout & Package

MP6400DJ-12-LF-Z is housed in a 6-pin TSOT23 package (2.9mm × 1.6mm × 1.0mm), optimized for space-constrained portable designs. The package features gull-wing leads, exposed pad not present, and JEDEC MO-193 AB compliance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G12DBVR and MAX6326LT12+T, MP6400DJ-12-LF-Z uniquely combines ultra-low IQ, factory-trimmed 1.12V threshold, MR input, and three discrete delay modes - making it optimal for space- and power-constrained systems needing configurable reset behavior.

Availability

MP6400DJ-12-LF-Z is available at Aetrix Electronics and suitable for battery-powered microcontrollers, laptop power sequencing, FPGA configuration integrity, and industrial handheld terminals requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for MP6400DJ-12-LF-Z 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

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance analog and mixed-signal ICs for power management, motion control, and sensing applications.

The MP6400 family targets ultra-low-power supervisory functions in portable, battery-operated, and industrial systems where precision voltage monitoring, flexible reset timing, and minimal standby current are critical.

FAQ

What is the exact SENSE threshold voltage for MP6400DJ-12-LF-Z?

The MP6400DJ-12-LF-Z has a factory-set SENSE threshold (VIT) of 1.12V ±1% at +25°C, corresponding to nominal 1.2V rail supervision. This value is laser-trimmed during production and remains stable across −40°C to +85°C with no external components required.

Can the CDELAY pin be left unconnected to achieve the 24ms delay?

Yes - leaving the CDELAY pin floating (unconnected) configures the device for a guaranteed 24ms reset delay. No pull-up or pull-down is needed; the internal circuitry detects the high-impedance state and selects this fixed timing mode per datasheet Rev. 1.1, page 4.

Does MP6400DJ-12-LF-Z support monitoring voltages below 1.2V?

No - MP6400DJ-12-LF-Z is factory-configured for 1.2V nominal rail supervision with 1.12V threshold. For adjustable monitoring down to 0.4V, use MP6400DJ-01. The "-12" suffix denotes fixed 1.2V functionality and cannot be reconfigured externally.

What is the minimum pull-up resistor value for the RESET output?

The RESET output requires an external pull-up resistor greater than 10kΩ to ensure proper logic-high level and avoid excessive current draw. With 5mA sink capability, a 10kΩ resistor yields ≤33mA worst-case current at 5V pull-up - but 47kΩ to 100kΩ is typical for low-power systems.

Is the MR pin compatible with 1.8V logic levels?

Yes - MR logic thresholds scale with VCC: VIH ≥0.7VCC and VIL ≤0.25VCC. At VCC = 1.8V, MR recognizes ≥1.26V as high and ≤0.45V as low. Its internal 90kΩ pull-up ensures reliable default-high state without external biasing.

How does SENSE transient immunity affect real-world noise rejection?

The MP6400DJ-12-LF-Z rejects negative SENSE transients ≤17.5µs duration when overdriven by 5% below VIT. This prevents false resets from brief coupling events (e.g., switching regulator ripple or ESD-induced dips), confirmed by test data in Figure 8 of the datasheet.

What is the maximum allowable voltage on the RESET pin when pulled up externally?

The RESET pin supports external pull-up voltages up to 6V, independent of VCC - enabling interface with higher-voltage logic families or shared reset buses. This is specified in Absolute Maximum Ratings and validated in Typical Application Figure 3.