SC4519H is a 600kHz, 3A step-down switching regulator from Semtech that features an integrated switch, operates at 600kHz with separate sync and enable functions. The integrated switch allows for cost effective low power solutions (peak switch current 3 amps). The sync function allows customers to synchronize to a faster clock in order to avoid frequency beating in noise sensitive applications. High frequency of operation allows for very small passive components. Current mode operation allows for fast dynamic response and instantaneous duty cycle adjustment as the input varies (ideal for CPE applications where the input is a wall plug power). The low shutdown current makes it ideal for portable applications where battery life is important. SC4519H is a 600kHz switching regulator synchronizable to a faster frequency from 750kHz to 1.2MHz.
The SC4519H is a current mode switching regulator featuring an integrated NPN power switch capable of handling peak currents of 3 amps. It operates at a fixed frequency of 600kHz but can be synchronized to external clocks ranging from 750kHz to 1.2MHz to avoid frequency beating in noise-sensitive applications.
The device includes features such as undervoltage lockout, overcurrent protection with hysteresis, and a precision enable threshold for low-power standby modes. It is available in an SO-8 EDP package and is designed for use in XDSL modems, CPE equipment, and portable DC-DC point-of-load applications.
| Operating Input Voltage | -0.3 to +28 V |
|---|---|
| Maximum Switch Current Limit | 5.5 A (Typ 3.5 A) |
| Oscillator Frequency | 600 kHz (Typ) |
| Switch On Voltage Drop | 220 mV (at 3A) |
| Feedback Voltage | 0.8 V (Typ) |
| Operating Ambient Temperature Range | -40 to +85 °C |
| Package Type | SO-8 EDP |
The internal oscillator sets the PWM frequency at 600kHz without external components.
The regulator can synchronize to an external clock with a frequency between 700kHz and 1.2MHz.
Pulling and holding the EN pin below 0.4V activates the shutdown mode.