Monolithic Power Systems Inc. EV26123-R-00A

Overview

EV26123-R-00A from Monolithic Power Systems is an evaluation board for the MP26123 switching Li-ion battery charger IC, supporting 2-cell (8.4V) or 3-cell (12.6V) configurations with up to 2A charge current, 600kHz fixed-frequency operation, ±0.75% battery voltage accuracy, and integrated thermal/NTC/battery-full protection.

For engineers reviewing the EV26123-R-00A datasheet, EV26123-R-00A pinout, EV26123-R-00A application, or EV26123-R-00A equivalent, this board enables rapid validation of high-accuracy CC/CV charging, preconditioning for deeply depleted batteries, power-path readiness, and fault status indication via dual LEDs in real-world portable power systems.

Technical Context

The EV26123-R-00A implements the MP26123 QFN-16 (4mm×4mm) IC with internal power MOSFET, enabling standalone switching charge control without external FETs. It uses dual feedback loops for precise constant-current (2A max) and constant-voltage (8.4V/12.6V) regulation across 10–24V input range.

Board-level features include RS2-based current sensing (100mΩ), CELLS/VREF33 jumper for cell count selection, EN pin for digital enable/disable (0.4V/1.8V thresholds), and discrete LED indicators (LED1 = input power good, LED2 = charge active/fault state).

Key Specifications

Availability

EV26123-R-00A is available at Aetrix Electronics and suitable for battery-powered portable electronics development, Li-ion pack qualification, and embedded power subsystem validation requiring stable component supply and documented reference design fidelity.

Supply support for EV26123-R-00A 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 core expertise in DC/DC converters, battery chargers, and motor drivers for consumer, industrial, and automotive applications.

The MP26123 product line delivers highly integrated, thermally robust switching Li-ion chargers targeting space-constrained portable devices needing accurate CC/CV profiles, NTC monitoring, and fault-resilient operation without external power switches.

FAQ

What battery configurations does the EV26123-R-00A support?

The board supports both 2-cell (8.4V nominal) and 3-cell (12.6V nominal) Li-ion battery packs. Default configuration is 2-cell; connecting the CELLS pin to VREF33 reconfigures the MP26123 for 3-cell operation using its internal voltage-divider reference.

How is charge current set on this evaluation board?

Charge current is set by the value of sense resistor RS2 (100mΩ installed). Using the formula I_CHG = 200 mV / R_S2, the default yields 2A. Swapping RS2 allows precise adjustment - e.g., 200mΩ sets 1A - with no firmware or register changes required.

What do the two LEDs indicate during operation?

LED1 (green) illuminates when valid input power (10–24V) is present at VCC/GND. LED2 (red) indicates active charging when steady-on; it turns off for full-battery termination, NTC fault, timeout, thermal shutdown, or EN disable, and blinks if BATT is floating (no battery connected).

Does the board support power-path functionality out of the box?

No - power-path operation requires external components (MP8110, RG1/RG2, C8/C9, RS1, M1/M2) not populated on the base EV26123-R-00A. These are marked "NC" in the BOM and must be added per MPS application guidance for simultaneous system power and battery charging.

Is thermal protection implemented on this evaluation board?

Yes - the MP26123 IC includes internal thermal shutdown, and the board layout provides copper thermal relief under U1 (QFN-16). The IC disables charging when junction temperature exceeds safe threshold, and LED2 turns off to signal the fault condition.

Can the switching frequency be adjusted?

No - the MP26123 operates at a fixed 600kHz switching frequency. This eliminates external timing components and ensures consistent EMI behavior, but precludes frequency tuning for noise-sensitive or efficiency-optimized designs.