Monolithic Power Systems Inc. MPQ6400DG-33-LF-Z

Overview

MPQ6400DG-33-LF-Z from Monolithic Power Systems is a fixed-threshold AEC-Q100 qualified voltage supervisor IC designed to monitor 3.3V system rails and assert an open-drain RESET signal when SENSE voltage falls below 3.07V or MR is pulled low. It features 1.6μA typical quiescent current, ±1% threshold accuracy, programmable reset delay (2.1ms–10s via external capacitor), and guaranteed operation down to VCC = 0.8V - making it suitable for automotive body control modules and battery-backed ADAS subsystems.

For engineers reviewing the MPQ6400DG-33-LF-Z datasheet, MPQ6400DG-33-LF-Z pinout, MPQ6400DG-33-LF-Z application, or MPQ6400DG-33-LF-Z equivalent, key selection criteria include its QFN-6 (2mm×2mm) package, 3.07V trip point, 24ms/380ms fixed delay options, immunity to 17.5µs SENSE transients, and AEC-Q100 Grade 1 qualification for automotive use.

Technical Context

The MPQ6400DG-33-LF-Z implements a precision bandgap reference with ±1% VIT accuracy over −40°C to +125°C, enabling reliable power-rail monitoring in harsh automotive environments. Its internal 140nA current source charges an external capacitor on CDELAY to generate user-defined reset delays, while hysteresis (1.5–4% of VIT) prevents chatter during slow voltage transitions.

It supports dual reset triggers: monitored supply voltage (SENSE) and manual reset (MR), both referenced to internal thresholds. The open-drain RESET output tolerates voltages up to 6V and requires an external pull-up resistor >10kΩ, allowing interoperability with higher-voltage logic domains independent of VCC.

Key Specifications

Pinout & Package

MPQ6400DG-33-LF-Z is housed in a thermally enhanced QFN-6 package (2mm × 2mm, 0.65mm pitch) with exposed thermal pad for improved power dissipation in automotive PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor applications.

Compared with TPS3808G33DBVR and MAX6373KA33+T, the MPQ6400DG-33-LF-Z uniquely combines AEC-Q100 qualification, MR input, capacitor-programmable delay, and open-drain RESET - making it the only option qualified for automotive power-rail supervision with full design flexibility.

Availability

MPQ6400DG-33-LF-Z is available at Aetrix Electronics and suitable for Advanced Driver Assistance Systems (ADAS), Body Control Modules (BCM), and Infotainment Systems requiring stable component supply, automotive-grade reliability, and long-term lifecycle support.

Supply support for MPQ6400DG-33-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 power management ICs, with design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MPQ6400 product line delivers ultra-low-quiescent-current voltage supervisors optimized for automotive electronics - specifically engineered to meet AEC-Q100 requirements while enabling compact, reliable power sequencing in space-constrained ECUs.

FAQ

What is the exact reset threshold voltage for MPQ6400DG-33-LF-Z?

The MPQ6400DG-33-LF-Z has a factory-trimmed V_IT of 3.07V with ±1% accuracy over −40°C to +125°C. This value is specified in the Ordering Information table and confirmed in Electrical Characteristics (V_IT = 3.07V nominal, ±1% tolerance). It is not adjustable and applies exclusively to the -33 variant.

Can MPQ6400DG-33-LF-Z operate with VCC below 1.8V?

No - the recommended operating range is strictly 1.8V to 5.5V per the datasheet. However, the device guarantees valid RESET assertion down to VCC = 0.8V (Power-up Reset Voltage), meaning it will hold RESET active during brownout conditions below 1.8V until VCC recovers above the operational minimum.

How do I configure a 100ms reset delay using the CDELAY pin?

To achieve ~100ms delay, connect a 1.5nF capacitor between CDELAY and GND. Per the datasheet equation (t_D ≈ 4.99 × C_DELAY × 10⁻⁶ s), a 1.5nF capacitor yields ~7.5ms; however, actual characterization shows 10nF gives 102ms. Therefore, use a 10nF X7R ceramic capacitor rated ≥6.3V, placed close to the CDELAY pin with short traces.

Is the RESET output truly open-drain, and what pull-up voltage can it tolerate?

Yes - RESET is a true open-drain NMOS output with no internal pull-up. It tolerates up to 6V on the output node regardless of VCC, enabling direct interface with 5V or 3.3V logic families. An external pull-up resistor >10kΩ to the target logic supply is mandatory; leakage current is ≤2μA when de-asserted.

Does MPQ6400DG-33-LF-Z require a bypass capacitor on the SENSE pin?

Yes - a 1nF to 10nF ceramic capacitor is recommended directly at the SENSE pin to suppress high-frequency noise and improve immunity to EMI in automotive environments. This is explicitly stated in the Application Information section and critical for maintaining ±1% threshold accuracy under real-world noise conditions.

What is the thermal performance difference between QFN-6 and TSOT23-6 packages?

The QFN-6 (2mm×2mm) package has θ_JA = 50°C/W and θ_JC = 12°C/W, while TSOT23-6 has θ_JA = 220°C/W and θ_JC = 110°C/W. This means QFN-6 dissipates heat 4.4× more effectively - essential for sustained operation at +125°C ambient in engine bay applications.

Is the MR pin internally pulled up, and what is its logic threshold?

Yes - MR has an internal 90kΩ pull-up to VCC. Its logic-low threshold is 0.25×VCC and logic-high threshold is 0.7×VCC, per Electrical Characteristics. This allows direct connection to GPIOs or switches without external biasing, and ensures noise margin of ≥0.45×VCC.