VPC2188

The VPC218X series is a highly integrated power control IC compatible with multiple topologies (Flyback, Buck, Boost) and output voltage feedback methods (SSR, PSR, resistive voltage divider). It integrates an ultra-wide-range startup circuit supporting input voltages from as low as 4V up to 100V. The internally integrated anti-backflow diode prevents reverse current flow from the VDD pin to the VIN pin. The VPC218X integrates an internal current-sense differential amplifier to significantly improve the sampling SNR, reducing the current-limiting threshold voltage at the CS pin to 156mV. This substantially lowers the power dissipation of the current-sensing circuit. The current-transformer-free design reduces cost and improves reliability. Under heavy load conditions, the VPC218X controller operates at a fixed maximum switching frequency with PWM modulation. As the load decreases to a certain level, the controller optimizes efficiency across the full load range through a multi-step analog frequency reduction mode, while achieving low ripple voltage and no-load power consumption under light-load conditions. The VPC218X supports PSR feedback at switching frequencies up to hundreds of kHz. The built-in output voltage sampling circuit operates in both CCM and DCM modes, with a minimum sampling voltage time window requirement as low as 350nS. The built-in loop compensation circuit with fast dynamic response ensures excellent stability and dynamic performance of the switching power supply. The VPC218X features precisely programmable input UVP with hysteresis, output short-circuit protection, output OVP, and OTP, ensuring high reliability of the switching power supply across all operating conditions. The VPC218X is a highly integrated current-mode PWM controller suitable for a wide range of switching power supply topologies including Flyback, Buck, and Boost. It integrates a high-voltage startup circuit and anti-backflow diode for a simple peripheral startup circuit. The integrated current differential amplifier improves the SNR of current sensing and enables ultra-low current threshold comparison. Multiple loop feedback methods are integrated, among which the high-speed sampling circuit for PSR feedback enables optocoupler-free isolated switching power supplies operating at frequencies up to hundreds of kHz. Every effort has been made to optimize each performance parameter of the switching power supply. An external programmable soft-start function allows the soft-start time to be configured as needed to reduce startup stress and output overshoot. Built-in slope compensation prevents sub-harmonic oscillation. All protection triggers incorporate delay filtering to prevent false triggering from noise. In all protection states, unused modules are shut down to minimize power consumption. Under extremely light load conditions, the device enters a deep frequency reduction mode to reduce no-load power consumption while keeping ripple within acceptable limits and preventing audible noise. Comprehensive protection features are also provided for the switching power supply: the UVP pin allows programmable input under-voltage protection threshold and hysteresis; the VDD pin implements output OVP; the COM pin implements output overload and open-loop protection; and the CS pin implements transformer or output short-circuit protection.

Applications

• Discontinuous (DCM)/Continuous (CCM) mode flyback converter
• Industrial power conversion
• BMS auxiliary power supply
• POE power supply
• Isolated communication power supply

Key features

• Ultra-wide input voltage range 4V~100V startup circuit
• Compatible with Flyback, Boost, and Buck topologies
• Selectable current limiting threshold voltage: 156mV or 500mV
• Single-resistor programmable oscillator frequency
• Light-load burst-mode analog frequency reduction for optimized efficiency curve; no-load burst operation for low standby power; enable shutdown current as low as 0.1uA
• Cycle-by-cycle current limiting protection, short-circuit protection, and over-temperature protection
• Leading-edge blanking for current sense signal
• Built-in slope compensation circuit
• Precisely configurable input undervoltage protection and hysteresis
• Selectable internal or external soft-start
• Built-in PSR loop control in CCM/DCM mode
• Direct optocoupler interface
• MSOP10 ultra-compact package