Monolithic Power Systems Inc. MP26075EQ-41-LF-Z

Overview

MP26075EQ-41-LF-Z from Monolithic Power Systems is a linear, high-efficiency single-cell Li-ion/Li-polymer cradle charger IC designed for AC adapter–fed plug-in charging systems. It regulates battery voltage at 4.10 V ±40 mV, delivers up to 1.2 A constant charge current, supports NTC-based temperature monitoring, and implements controlled power-up sequencing with input OVP (6.3 V) and UVLO (2.0 V). It is used in compact portable devices requiring safe, adaptive charging with dual LED status indication.

For engineers reviewing the MP26075EQ-41-LF-Z datasheet, MP26075EQ-41-LF-Z pinout, MP26075EQ-41-LF-Z application, or MP26075EQ-41-LF-Z equivalent, this device is selected for cradle-style chargers where flyback controller feedback via photo-coupler (CTL/COM), precise CV/CC transition at 3.0 V, and auto-recharge at 8% VBATT drop are required - not for USB-PD, wireless, or multi-cell topologies.

Technical Context

The MP26075EQ-41-LF-Z operates as a secondary-side linear charger that dynamically controls AC adapter output voltage via CTL pin feedback to the primary-side flyback controller using an optocoupler. Its internal oscillator (TMR pin, 7 Hz with 0.1 μF) governs pre-charge (512 cycles), trickle (16,384 cycles), and total charge (262,144 cycles) timers.

It integrates a precision NTC window comparator (VNTC_LOW = 0.37 V, VNTC_HIGH = 2.16 V), thermal foldback protection (120 °C junction limit), and dual open-drain LED drivers (LED-R/LED-G) with defined fault states: both pins float on timer timeout or NTC fault, both high on general fault, LED-R low/LED-G high during active charge, and vice versa at termination.

Key Specifications

Pinout & Package

MP26075EQ-41-LF-Z is housed in a thermally enhanced QFN-10 package (3 mm × 3 mm, 0.75 mm height) with exposed thermal pad. The package supports high-power dissipation (θ_JA = 50 °C/W on 4-layer board) and requires soldering of the exposed pad to PCB ground plane for optimal thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar single-cell Li-ion cradle charger applications.

Compared with BQ24075RGTR and MAX1555, MP26075EQ-41-LF-Z uniquely combines programmable 4.10 V regulation, analog optocoupler feedback for adapter control, integrated NTC window comparator, and autonomous hardware timers - making it the only option for standalone, MCU-free, high-safety cradle chargers with AC adapter input.

Availability

MP26075EQ-41-LF-Z is available at Aetrix Electronics and suitable for smartphone cradles, portable media player docks, digital camera battery chargers, and industrial PDA charging stations requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for MP26075EQ-41-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 mixed-signal ICs for power management, motor drive, and automotive applications.

The MP26075 belongs to MPS's battery management IC product line, engineered specifically for cost-sensitive, high-efficiency cradle and dock-style chargers where analog feedback, thermal safety, and autonomous operation are critical design requirements.

FAQ

What battery chemistry and cell count does MP26075EQ-41-LF-Z support?

MP26075EQ-41-LF-Z supports single-cell lithium-ion and lithium-polymer batteries only, with a fixed regulation voltage of 4.10 V. It is not compatible with LiFePO₄, NiMH, multi-cell stacks, or batteries requiring >4.20 V or <4.05 V regulation. The IC enforces strict voltage thresholds and NTC-based thermal validation before initiating charge.

How is charge current programmed, and what is the tolerance?

Charge current is set by connecting a resistor (R_CHG) between ISET and GND. Using the formula I_CHG = (1.23 V / R_CHG) × 1400, a 1.7 kΩ resistor yields 1.0 A nominal. The datasheet specifies ±20% variation over temperature and process, with typical deviation ≤±15% at 25°C and ±100 mA absolute error across –20°C to +85°C.

Can MP26075EQ-41-LF-Z operate without a microcontroller?

Yes - MP26075EQ-41-LF-Z is fully autonomous. It executes pre-charge, trickle, CC, and CV stages using internal oscillators and comparators, signals status via LED-R/LED-G pins, and handles faults (NTC, timer, OVP) without external logic. No firmware, I²C, or host intervention is required for basic operation.

What is the role of the CTL and COM pins in system-level design?

CTL sinks current to drive the optocoupler LED, enabling real-time adjustment of the flyback controller's COMP pin voltage. COM provides compensation for the feedback loop; a series RC network (e.g., 10 kΩ + 100 nF) between COM and CTL stabilizes the closed-loop response and prevents oscillation during dynamic load changes.

Does MP26075EQ-41-LF-Z support USB input or 5 V wall adapters directly?

Yes - it accepts 2.2 V to 6.3 V DC input, making it compatible with standard 5 V USB power supplies and regulated 5 V flyback outputs. However, for cradle applications, it is intended to work with adjustable flyback adapters where CTL feedback actively trims output voltage to match battery state, not fixed 5 V sources alone.

How does the NTC interface function, and what thermistor values are supported?

The NTC pin forms a resistive divider with a fixed resistor from VIN. The IC compares the resulting voltage against 0.37 V (low trip) and 2.16 V (high trip). With VIN = 5 V, a 10 kΩ series resistor supports common NTCs (e.g., 10 kΩ @ 25°C), yielding ~2.5 V at 0°C and ~0.3 V at 60°C - covering typical battery operating ranges.

What happens during thermal foldback, and how does it affect charge time?

At 120 °C junction temperature, the IC reduces average charge current to limit power dissipation. This extends CC phase duration but maintains CV regulation integrity. Charge resumes full current once die temperature falls below 110 °C hysteresis. In worst-case ambient (+85°C) with minimal copper area, full charge may extend by 15–25%.