Monolithic Power Systems Inc. MPF42797DRT-0B-0000-Z

Overview

MPF42797DRT-0B-0000-Z from Monolithic Power Systems is a 2–10 series stacked-cell lithium-ion battery fuel gauge IC that estimates per-cell and pack state-of-charge (SOC) and state-of-health (SOH), remaining runtime, charge time, and instantaneous available power. It operates with a 400kHz I²C interface, supports adaptive learning for degradation tracking, and integrates lifetime parameter logging. It targets high-accuracy BMS applications in light EVs and energy storage.

For engineers reviewing the MPF42797DRT-0B-0000-Z datasheet, MPF42797DRT-0B-0000-Z pinout, MPF42797DRT-0B-0000-Z application, or MPF42797DRT-0B-0000-Z equivalent, key selection factors include ±3% SOC accuracy when paired with MP279x AFEs, TQFN-32 package compatibility, 135µA average operating current during rest, and support for CRC-protected I²C communication up to 400kHz.

Technical Context

The MPF42797DRT-0B-0000-Z functions as a host-controlled fuel gauge engine, requiring periodic input of cell voltages (up to 10 cells), pack current, and temperature via I²C from an external AFE such as the MP279x family. It executes real-time SOC/SOH estimation using adaptive algorithms that refine initial charge/discharge settings and track individual cell degradation over time.

Its operation relies on three distinct modes: Active (fuel gauge update + I²C communication), Standby (idle waiting for SDA activity), and Disabled (CE low, 6µA quiescent current, memory retention). Configuration is performed via dedicated commands (CONFIG_MODE_CMD, EDIT_CONFIG_CMD) with non-volatile storage of settings in on-chip NVM.

Key Specifications

Pinout & Package

The MPF42797DRT-0B-0000-Z is housed in a TQFN-32 (4mm × 4mm) package with an exposed GND pad (Pin 33) requiring solder connection for thermal and electrical integrity. The package supports reflow-compatible assembly and provides low thermal resistance (θ_JA = 47°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar battery fuel gauge applications.

Compared with BQ34Z100-G1 and MAX17055, the MPF42797DRT-0B-0000-Z uniquely combines AFE-agnostic host-controlled architecture, per-cell adaptive SOH tracking, and on-device lifetime logging-making it optimal for industrial and light EV systems where AFE co-design and long-term field analytics are prioritized.

Availability

MPF42797DRT-0B-0000-Z is available at Aetrix Electronics and suitable for light EV battery management, energy storage system monitoring, and industrial mobile robot power applications requiring stable component supply, full traceability, and lifecycle continuity.

Supply support for MPF42797DRT-0B-0000-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 expertise in DC/DC converters, battery management, and motor drivers.

The MPF42797 belongs to MPS's fuel gauge product line, engineered specifically for high-accuracy, host-managed battery state estimation in multi-cell lithium-based systems used in mobility and grid-edge storage.

FAQ

What is the minimum system requirement to use MPF42797DRT-0B-0000-Z?

The device requires an external analog front-end (e.g., MP279x) to provide individual cell voltages (2–10 series), pack current, and temperature readings. A host MCU with I²C interface, interrupt capability, ≥48kB Flash, and ≥4kB RAM is mandatory to manage configuration, data ingestion, and fuel gauge execution triggers.

Does MPF42797DRT-0B-0000-Z support standalone operation without an AFE?

No. The MPF42797DRT-0B-0000-Z is a host-controlled fuel gauge engine and does not include ADCs or cell monitoring circuitry. It relies entirely on externally supplied voltage, current, and temperature data via I²C registers - it cannot function without a companion AFE or battery monitor.

How is SOC accuracy validated, and what conditions affect it?

SOC accuracy is validated using Samsung INR18650-25R 10S1P packs with MP279x AFEs, achieving ±3% error at 10°C–50°C and ≤2C load. Accuracy degrades outside this range or with uncharacterized cell chemistries; adaptive learning improves long-term consistency but requires initial calibration.

Can the default I²C address be changed, and how is CRC enabled?

Yes. The default slave address is 0x08 and is configurable via register write. CRC is enabled by writing to the CONFIG_CRC_EN register; when active, the last 4 bytes of each transaction are CRC-32 checksums computed over register address, length, and payload using the specified polynomial (0x04C11DB7).

What happens to internal state during CE pin assertion?

When CE is pulled low, the MPF42797DRT-0B-0000-Z enters Disabled mode: I²C communication halts, fuel gauge updates stop, and current drops to 6µA. All internal state variables (SOC, SOH, learned parameters) are retained in volatile memory - no data loss occurs during brief disable periods.

Is lifetime logging persistent across power cycles?

No. Lifetime logging data resides in volatile RAM and is lost upon power removal. To retain logs, the host MCU must periodically read and store values from the LOG_* registers in external non-volatile memory before system shutdown or reset.

Does MPF42797DRT-0B-0000-Z support LiFePO₄ or NMC chemistries out of the box?

Yes. The device supports a wide variety of lithium chemistries including LiCoO₂, NMC, and LiFePO₄. Default models are provided, but optimal accuracy requires chemistry-specific characterization and optional model tuning via configuration registers.