Monolithic Power Systems Inc. MP6400DJ-09-LF-Z

Overview

MP6400DJ-09-LF-Z from Monolithic Power Systems is a fixed-threshold supervisory circuit with 0.84V sense voltage, 1.6μA typical quiescent current, ±1% threshold accuracy, and programmable reset delay (2.1ms–10s via CDELAY pin), designed for power-on reset generation in low-voltage microcontroller systems operating down to 0.8V VCC.

For engineers reviewing the MP6400DJ-09-LF-Z datasheet, MP6400DJ-09-LF-Z pinout, MP6400DJ-09-LF-Z application, or MP6400DJ-09-LF-Z equivalent, this device supports battery-powered embedded systems requiring precise voltage monitoring, manual reset control, open-drain reset assertion, and immunity to short SENSE transients up to 17.5μs.

Technical Context

The MP6400DJ-09-LF-Z implements a precision bandgap reference and comparator-based supervision architecture with internal 90kΩ MR pull-up, enabling dual-trigger reset assertion-either when SENSE falls below 0.84V or MR drops below 0.25×VCC. Its reset output remains asserted until both inputs exceed thresholds plus hysteresis (1.5–3.5% of VIT), then releases after a user-configured delay.

Delay timing is controlled by an internal 140nA current source charging an external capacitor on CDELAY; voltage across the capacitor is monitored until it reaches 1.13V, at which point RESET de-asserts. The device guarantees valid reset operation down to VCC = 0.8V and supports SENSE input transients up to 5% overdrive for ≤17.5μs without false triggering.

Key Specifications

Pinout & Package

MP6400DJ-09-LF-Z is housed in a TSOT23-6 package (2.9mm × 1.6mm × 1.0mm height), RoHS-compliant and lead-free, with exposed pad not connected internally. Pin 1 is bottom-left when top marking "AAG" is read left-to-right.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G01QDBVRQ1 and MAX6326UR29+T, MP6400DJ-09-LF-Z delivers the narrowest threshold tolerance (±1%), lowest quiescent current (1.6μA), and widest programmable delay range (2.1ms–10s), making it optimal for space-constrained, battery-sensitive, and timing-flexible embedded systems.

Availability

MP6400DJ-09-LF-Z is available at Aetrix Electronics and suitable for battery-powered IoT sensors, laptop platform power sequencing, FPGA configuration integrity monitoring, and industrial PLC controller boot guard applications requiring stable component supply and long-term lifecycle assurance.

Supply support for MP6400DJ-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-performance analog and power ICs, with design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MP6400 product line targets ultra-low-power supervisory functions in portable, battery-operated, and energy-sensitive systems, emphasizing precision thresholding, minimal IQ, and flexible reset timing without firmware dependency.

FAQ

What is the minimum VCC voltage at which MP6400DJ-09-LF-Z guarantees valid RESET assertion?

The device guarantees RESET assertion remains valid down to VCC = 0.8V, meaning it will correctly detect SENSE undervoltage and assert RESET even when supply voltage collapses near brown-out thresholds-critical for fail-safe shutdown in low-power systems before logic becomes unreliable.

Can the CDELAY pin be used without an external capacitor?

Yes: leaving CDELAY floating selects a fixed 24ms delay, while connecting it directly to VCC (via resistor 50kΩ–200kΩ) selects 380ms. No capacitor is required for these two preset delays; however, any delay between 2.1ms and 10s requires a capacitor ≥150pF from CDELAY to GND.

Is the RESET output compatible with 5V logic systems when VCC is 1.8V?

Yes: the open-drain RESET output tolerates up to 6V on the pin regardless of VCC, allowing direct connection to a 5V pull-up resistor. This enables interoperability across mixed-voltage domains without level-shifting components.

How does the MP6400DJ-09-LF-Z handle noise on the SENSE pin?

It incorporates built-in hysteresis (1.5–3.5% of VIT) and supports external 1nF–10nF bypass capacitors on SENSE. Combined with 17.5μs immunity to short negative transients at 5% overdrive, this eliminates need for additional RC filtering in most industrial and portable applications.

What is the function of the internal 90kΩ resistor on the MR pin?

The internal 90kΩ pull-up to VCC allows MR to float safely-no external component needed-while still permitting active-low manual reset assertion. It also defines MR's logic thresholds (VIL = 0.25×VCC, VIH = 0.7×VCC), ensuring compatibility with standard CMOS logic families.

Does MP6400DJ-09-LF-Z support adjustable threshold voltage?

No: MP6400DJ-09-LF-Z has a factory-set 0.84V threshold for monitoring 0.9V rails. Adjustable thresholds are only available in the MP6400DJ-01 variant, which uses an external resistor divider on the SENSE pin to monitor voltages ≥0.4V.