230W PFC+LLC E-Bike Charger Reference Design

February 05, 2020 by Paul Shepard

The MPSB005 from Monolithic Power Systems is an evaluation board for Lithium-ion chargers typically used in the e-Mobility applications. It also can be used as general power supply unit with minimum changes. The solution is based on a PFC+LLC combo solution from a single integrated circuit with digital control (for the PFC).

This solution offers an excellent relation performance-cost-space by avoiding the use of low frequency filters. Synchronous Rectification (SR) is included instead of diodes to increase the efficiency, besides, a constant current constant voltage control (CC-CV) that operates to guaranty a proper charge of the battery.

Also, high power density and excellent performance with low cost BOM are shown. Lithium-Ion batteries usually bring a battery management system (BMS) to maintain the battery in its safe operating area. This charger can interact with this type of system through a 5V output presence signal.

MPSB005 also implements a soft connection control (SCC), with minimum components, to avoid high current spikes in the output connection. This spikes typically triggers the BMS over current protection. SCC is achieved by balancing the converter voltage with the battery one before closing the relay.

MPSB005 block diagram (click on image to enlarge)

If extra control is needed the user can solder J4 connector and attach an MCU. Then direct interaction with current and voltage sensing signals as well as the relay control are possible.

Summary of Features

  • Wide operating input range (from 90V to 265V)
  • 230W rated power and constant voltage output
  • High efficiency up to 93%
  • Meets EuP lot 6 and COC version 5, Tier 2 specifications
  • Meets class C standard of IEC61000-3-2
  • Meets EN55032 class B standard
  • High power factor (PF)
  • Overload protection (auto-restart mode)
  • Over-voltage protection (OVP)
  • Anti-capacititive mode protection
  • Soft connection control (SCC)
  • Form factor 172 x 74 x 50 mm