Monolithic Power Systems Inc. MPQ6411GS-P

Overview

MPQ6411GS-P from Monolithic Power Systems is a windowed watchdog timer IC qualified to AEC-Q100 Grade 1 for automotive use, providing programmable short/long window monitoring of microcontroller health via WDI input, generating low-active reset (WDO) on timeout or power-up, with VCC options of 5V or 3.3V and MODE-selectable timing windows.

For engineers reviewing the MPQ6411GS-P datasheet, MPQ6411GS-P pinout, MPQ6411GS-P application, or MPQ6411GS-P equivalent, this device supports critical safety-critical MCU supervision in automotive ECUs where precise windowed timeout detection, POR/VOR reset assertion, and watchdog disable capability are required.

Technical Context

The MPQ6411GS-P implements a state-machine-based windowed watchdog with two distinct operational modes: short window (t₂=15 cycles, t₃=10 cycles) and long window (t₄=1500 cycles, t₅=1000 cycles), both derived from an external TIMER resistor (e.g., 51kΩ yields ~880µs base period). Its WDO output behavior differs by version: open-drain for 3.3V variants requiring pull-up, but inverter-output for 5V versions.

It integrates power-on reset (VPOR-HIGH = 4.6V typ, VPOR-LOW = 4.5V typ for 5V operation), watchdog disable (/WD_DIS with internal weak pull-up), and WDI error handling that holds WDO low if WDI remains low beyond 5ms. All functions operate across –40°C to +125°C junction temperature.

Key Specifications

Pinout & Package

MPQ6411GS-P is housed in an SOIC-8 package (JEDEC MS-012 AA, 150 mil width), with exposed pad not present and pin 1 marked by notch or dot. Pin functions are validated per official MPS datasheet Rev. 1.1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar windowed watchdog timer applications.

Compared with NCP380LSN33T1G and TPS3808G33DBVR, the MPQ6411GS-P uniquely delivers AEC-Q100 Grade 1 compliance, dual-mode windowed supervision, and 5V operation - making it the only option for automotive-grade, timing-precision-critical MCU monitoring where false resets must be avoided.

Availability

MPQ6411GS-P is available at Aetrix Electronics and suitable for automotive engine control units, ADAS camera modules, and electric power steering controllers requiring stable component supply with full AEC-Q100 traceability and long-term lifecycle support.

Supply support for MPQ6411GS-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, and global manufacturing partnerships.

The MPQ6411 belongs to MPS's automotive-grade watchdog timer product line, engineered specifically for functional safety-critical MCU supervision in harsh-temperature automotive environments.

FAQ

What is the exact supply voltage range supported by MPQ6411GS-P?

The MPQ6411GS-P is specified for 5V ±10% operation (4.5V to 5.5V), with power-on reset thresholds of 4.4V (rising) and 4.3V (falling). It is not rated for 3.3V operation - that function is implemented in the MPQ6411GS-33 variant.

How does the MODE pin affect watchdog timing behavior?

When MODE is pulled low, the device enters short window mode: t₂=15 cycles (close window) and t₃=10 cycles (open window). When MODE is high, it enters long window mode: t₄=1500 cycles and t₅=1000 cycles. The base cycle time depends on RTIMER (e.g., 51kΩ → ~880µs/cycle).

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

No - unlike the 3.3V variant, the MPQ6411GS-P (5V version) uses an inverter-output WDO stage, so it actively drives low and high without requiring an external pull-up. This simplifies PCB layout and reduces BOM count.

What happens if the WDI signal stays low longer than allowed?

If WDI remains low for more than 5ms (maximum WDI_OK pulse width), the device interprets it as a WDI error and holds WDO low until WDI returns high - preventing MCU execution while invalid trigger conditions persist.

Can /WD_DIS be left unconnected in a production design?

Yes - /WD_DIS has a weak internal pull-up, so leaving it floating defaults the watchdog to enabled state. However, for safety-critical applications, explicitly tying it high via a 10kΩ resistor is recommended to ensure deterministic enablement.

What is the thermal performance limit for continuous operation?

The SOIC-8 package has θJA = 96°C/W. At TA = 85°C, maximum continuous power dissipation is PD(MAX) = (150°C − 85°C)/96°C/W ≈ 677mW. With IQ ≈ 19µA at 5V, static power is only 95µW - thermal headroom is ample for typical use.

Does MPQ6411GS-P support I²C or SPI configuration?

No - the MPQ6411GS-P is a hardware-configured watchdog timer with no serial interface. Timing, mode, and enable functions are set solely via external resistor (TIMER), MODE pin voltage, and /WD_DIS pin state.