NCP1589LMNTWG

NCP1589LMNTWG Application Field and Working Principle

NCP1589LMNTWG is a switching DC to DC controller with a comprehensive feature set, specifically designed to reduce the development effort and production time of the designers in power conversion applications. These products have a wide application field, including step-down, flyback, and positive or negative conversion DC to DC converters with up to 300V bus voltage.

Features of NCP1589L-MNTWG

• Input voltage range : 3.4V–30V (VIN)
• Output voltage range : 0.8V – 30V (VOUT)
• Output Current : up to 20A
• Internal power MOSFET : 50mΩ N-channel and 90mΩ P-channel
• Maximum Input Dierential Voltage : 30V
• Cycle-by-cycle current limiting
• On-chip power sense resistor (PSR) comparator
• UVLO and OVLO protection
• PSR oset Voltage Adjustment
• Low < 1mΩ ESR output capacitor

NCP1589-MNTWG Working Principle

NCP1589LMNTWG is a DC/DC switching controller that uses the primary-side regulation (PSR) technique to produce regulated outputs through a single-inductor-based DC/DC converter. The controller contains a complete 500kHz oscillator, a PSR sense comparator, a logic comparator, a driver circuit, and other safety and power loss protection circuits. The device has an on-chip power resistor for current sensing, UVLO, OVLO, and current limit functions.

The PSR comparator monitors the voltage on the power resistor by continuously comparing the power resistor’s voltage to the reference voltage, and adjusts the duty cycle at each switching cycle. With the PSR control technique, the output voltage can be monitored and regulated without requiring an external feedback loop. This primary-side regulation eliminates the need of a complicated and expensive secondary-side feedback loop, thus saving design complexity and cost.

The NCP1589-MNTWG has an over current protection (OCP) circuit, the comparator will detect the current sense voltage drop across the power resistor below a predetermined reference voltage. An internal timer circuit then triggers the current limitation comparator to limit the output current. The OCP feature also provides a delay function, which prevents the PSR from interfering with a momentary surge above the OCP threshold.

Conclusion

NCP1589-MNTWG is a DC/DC switching controller with a comprehensive feature set, which is specifically designed to reduce the design effort and production time of the designers in power conversion applications. The PSR sensing technique and OCP features provides current and voltage regulation, efficiently reducing design complexity and cost.