Monolithic Power Systems Inc. MPQ2420GF-AEC1-P

Overview

MPQ2420GF-AEC1-P from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified synchronous step-down converter integrating high- and low-side 75V MOSFETs, delivering up to 0.3A output with 1.2Ω/0.45Ω R_DS(on), 4.5–75V input range, and integrated window watchdog for automotive safety-critical power rails.

For engineers reviewing the MPQ2420GF-AEC1-P datasheet, MPQ2420GF-AEC1-P pinout, MPQ2420GF-AEC1-P application, or MPQ2420GF-AEC1-P equivalent, key selection criteria include its 5μA shutdown current, programmable short/long watchdog window modes, ±1% FB tolerance at room temperature, and TSSOP-16 EP thermal performance (θ_JA = 45°C/W).

Technical Context

The MPQ2420GF-AEC1-P implements a current-mode PWM control architecture with zero-current detection (ZCD) for discontinuous conduction mode (DCM) operation, enabling light-load efficiency scaling via frequency reduction. Its internal 2.6V regulator powers core logic, while BIAS pin support allows external biasing for improved driver efficiency when V_BIAS > 2.9V.

Watchdog functionality operates independently of the DC/DC controller: TIMER pin sets timeout period (e.g., 880μs with 51kΩ), MODE selects short (t₂/t₃) or long (t₄/t₅) window timing, and /WD_DIS enables hardware disable. WDO provides open-drain reset signaling synchronized to MCU-triggered WDI pulses.

Key Specifications

Pinout & Package

TSSOP-16 EP package with exposed thermal pad soldered to PCB ground plane for optimal thermal dissipation (θ_JA = 45°C/W, θ_JC = 10°C/W on 4-layer board).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous step-down converter with watchdog applications.

Compared with MPQ2420GF-AEC1-P, the MPQ2420GJ-AEC1-Z trades thermal performance for footprint reduction, while the TPS63060-Q1 sacrifices high-voltage capability and integrated safety monitoring for wider VIN flexibility in non-load-dump environments.

Availability

MPQ2420GF-AEC1-P is available at Aetrix Electronics and suitable for automotive body control, ADAS camera power, EPS sensor interfaces, and telematics control units requiring stable component supply with AEC-Q100 Grade 1 assurance.

Supply support for MPQ2420GF-AEC1-P 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.

The MPQ2420 product line delivers AEC-Q100 qualified DC/DC converters with integrated safety features for automotive subsystems where reliability, small footprint, and functional safety are critical - especially in powertrain, chassis, and ADAS domains.

FAQ

What is the maximum allowable input voltage for continuous operation?

The MPQ2420GF-AEC1-P supports continuous operation up to 75V input. Its absolute maximum rating is 80V, but sustained operation above 75V risks exceeding safe operating area limits and triggering thermal shutdown. Designers must ensure transient suppression (e.g., TVS) handles load-dump spikes beyond 75V per ISO 7637-2.

How does the watchdog interact with the DC/DC converter during a reset event?

The watchdog circuit operates independently from the DC/DC controller using dedicated VCC and TIMER pins. When WDO asserts low, it resets the MCU but does not disable the buck converter - output remains regulated. This allows the MCU to reboot while maintaining power to peripherals, meeting ASIL-B diagnostic coverage requirements.

Can the BIAS pin be left unconnected in a typical automotive application?

Yes, BIAS can be left floating. The device defaults to powering internal circuitry from VIN. However, connecting BIAS to the regulated output (e.g., 3.3V or 5V) when within 2.9–5.5V improves efficiency by reducing driver losses and lowering quiescent current - recommended for battery-sensitive applications.

What is the minimum inductor value supported, and how is it calculated?

The minimum inductor is determined by the 115ns minimum on-time and maximum input voltage: L_MIN = (V_IN(MAX) × t_ON(MIN)) / I_PEAK. For 75V_IN and 810mA peak current, L_MIN ≈ 10.5μH. Using smaller inductors risks subharmonic oscillation and reduced efficiency; 15–33μH is typical for 0.3A automotive designs.

Does the POK output indicate regulation accuracy or just presence of output voltage?

POK asserts high only when V_OUT exceeds 90% of its nominal value (e.g., >2.97V for 3.3V output), based on FB voltage comparison. It does not guarantee tight regulation - FB tolerance (±2% over temperature) means actual output may vary ±2% around the setpoint while POK remains active.

How is the watchdog timeout period adjusted, and what is the tolerance?

Timeout is set by external resistor on TIMER pin: T (μs) = 15.75 × R_TIMER(kΩ) + 73.5. With 51kΩ, nominal T = 880μs ±10%. Tolerance arises from resistor tolerance and internal comparator offsets - design margin must account for ±20% total variation in safety-critical timing.

Is the /WD_DIS pin compatible with 3.3V logic in a mixed-voltage system?

Yes. /WD_DIS accepts logic-high ≥3.2V and logic-low ≤0.8V, making it compatible with both 3.3V and 5V CMOS outputs. Its input current is <1μA at 5V, so standard GPIOs can drive it directly without level-shifting - simplifying integration with 3.3V microcontrollers.