Monolithic Power Systems Inc. MP6400DG-09-LF-Z

Overview

MP6400DG-09-LF-Z from Monolithic Power Systems is a fixed-threshold supervisory circuit with 0.84V SENSE voltage threshold, ±1% threshold accuracy, 1.6μA typical quiescent current, and programmable reset delay from 2.1ms to 10s via external capacitor on CDELAY pin. It monitors 0.9V system rails in battery-powered microcontroller systems requiring reliable power-on reset and manual reset assertion.

For engineers reviewing the MP6400DG-09-LF-Z datasheet, MP6400DG-09-LF-Z pinout, MP6400DG-09-LF-Z application, or MP6400DG-09-LF-Z equivalent, key selection criteria include guaranteed RESET validity down to VCC = 0.8V, open-drain RESET output compatible with 6V pull-up, immunity to 17.5µs SENSE transients, and factory-set 0.84V threshold for 0.9V nominal supply monitoring.

Technical Context

The MP6400DG-09-LF-Z implements a precision voltage monitor with internal 140nA current source charging an external capacitor on CDELAY to generate user-programmable reset delays. Its comparator-based sensing architecture includes 1.5–3.5% hysteresis (VHYS) to reject noise on the SENSE input.

It features dual reset triggers: falling SENSE voltage below 0.84V (±1% accuracy) or logic-low assertion on MR pin (VIH = 0.7×VCC, VIL = 0.25×VCC), with MR internally pulled up to VCC via 90kΩ resistor. RESET remains asserted until both conditions clear and the programmed delay expires.

Key Specifications

Pinout & Package

MP6400DG-09-LF-Z is housed in a 2mm × 2mm QFN-6 package with exposed thermal pad, optimized for space-constrained portable PCB layouts and thermal performance (θJA = 50°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G01QDBVRQ1 and MAX6326UT29D3+, MP6400DG-09-LF-Z offers superior quiescent current efficiency and SENSE transient immunity for portable medical and industrial edge devices, while trading AEC-Q100 certification and fixed-delay simplicity for programmable timing flexibility.

Availability

MP6400DG-09-LF-Z is available at Aetrix Electronics and suitable for battery-powered wearables, FPGA configuration monitoring, medical point-of-care diagnostics, and automotive body control modules requiring stable component supply across extended production lifecycles.

Supply support for MP6400DG-09-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-efficiency analog and power ICs for computing, industrial, automotive, and communications markets.

The MP6400 product line delivers ultra-low-power supervisory circuits optimized for battery-critical applications where sub-2μA quiescent current, precise voltage thresholds, and flexible reset timing are mandatory design requirements.

FAQ

What is the exact SENSE voltage threshold for MP6400DG-09-LF-Z?

The MP6400DG-09-LF-Z has a factory-trimmed SENSE threshold voltage (VIT) of 0.84V with ±1% accuracy over –40°C to +85°C ambient temperature. This value is specified in the Standard Versions table of the datasheet and corresponds to nominal 0.9V rail monitoring with 6% headroom for tolerance and drift.

Can MP6400DG-09-LF-Z operate with VCC below 1.8V?

No - the recommended operating condition specifies minimum VCC = 1.8V. However, the device guarantees RESET assertion remains valid down to VCC = 0.8V, meaning it will hold RESET active during brown-out events below 1.8V, but full functional operation (e.g., delay timing, threshold comparison) is only assured above 1.8V.

How do I configure a 5-second reset delay using CDELAY?

To achieve ~5s delay, connect a 4.7nF ceramic capacitor between CDELAY (Pin 3) and GND (Pin 5). Using the formula td ≈ 4.99 × 10⁷ × CDELAY (in farads), a 4.7nF cap yields ~234ms; for 5s, use ~100nF. Confirm with oscilloscope measurement, as stray capacitance affects accuracy.

Is an external pull-up resistor required on the RESET pin?

Yes - RESET is open-drain and requires an external pull-up resistor ≥10kΩ to a logic-compatible voltage (up to 6V). The datasheet specifies this to ensure proper rise time and noise immunity; omitting it leaves RESET floating and causes undefined microprocessor behavior.

Does MP6400DG-09-LF-Z support monitoring voltages other than 0.9V?

No - MP6400DG-09-LF-Z is factory-configured for 0.84V threshold targeting 0.9V rails. For adjustable monitoring (e.g., 1.2V, 1.8V), select MP6400DG-01 or MP6400DJ-01 variants with external resistor divider capability; the -09 suffix denotes fixed 0.9V optimization.

What is the maximum capacitive load allowed on the SENSE pin?

The datasheet recommends a 1nF–10nF bypass capacitor on SENSE for noise immunity. While not explicitly rated for maximum load, exceeding 10nF risks slowing response time beyond the 17.5µs transient immunity window and may cause delayed reset assertion during rapid voltage drops.

How does the MR pin behave when left unconnected?

MR is internally pulled up to VCC via 90kΩ, so an unconnected MR remains logic-high and does not trigger RESET. This allows pushbutton-to-ground implementation without external pull-up resistors - pressing the button pulls MR to GND, asserting RESET immediately regardless of SENSE state.