NCP1571DG

NCP1571DG Application Field and Working Principle

NCP1571DG is a DC/DC buck switching converter controller designed for various voltage reduction and regulated voltage applications. It is part of the DC/DC switching converter controllers family in the Voltage Regulators category of the PMIC family.

Application Field

NCP1571DG is especially suitable for systems with a limited supply voltage, such as digital mobile phones, DSPs, notebook computers, and printers. It can be used to regulate system voltage levels in buck converter configurations from 1.2V to 30V, and provides excellent load regulation performance.

NCP1571DG devices can be used in wide temperature range from -40°C to +125°C, and it can provide up to 1.4A for steady state and transient loads. The device also features adjustable switching frequency that can be set from 200kHz to 1MHz. It also includes a low-noise Spread Spectrum Frequency Modulation (SSFM) to reduce EMI.

Working Principle

The NCP1571DG DC/DC switching controller consists of a high-speed current-mode pulse-width modulation (PWM) control circuit, error amplifiers, reference voltage circuits, a under-voltage-lockout (UVLO) circuit, a slope compensation, and a temperature shutdown circuit.

The PWM control circuit is the control center of the device, which works together with the error amplifier to generate PWM signals. This PWM signal is used to control the duration of the output voltage which is proportional to the input voltage applied to the converter. An internal voltage reference generator is incorporated to set the output voltage level precisely.

The PWM switching frequency is controlled by an internal oscillator and can be adjusted via an external potentiometer or an external clock input to lower the EMI application. It also comes with Spread Spectrum Frequency Modulation (SSFM) rate which can be adjusted to control the frequency modulated output from 50% to 75%.

The NCP1571DG also features over-voltage protection (OVP) and over-current protection (OCP) circuits to protect the converter from any accidental surge voltages or excessive load currents.

Conclusion

NCP1571DG is an excellent high-performance, cost-effective DC/DC switching converter controller designed for various voltage reduction and regulated voltage applications, such as digital mobile phones, DSPs, notebook computers, and printers. It is also designed to work in wide temperature range and provides up to 1.4A for steady state and transient loads, with adjustable switching frequency and Spread Spectrum Frequency Modulation (SSFM). It is equipped with over-voltage and over-current protection circuits for system protection.