Key facts
- Brand
- Semtech
- Model
- SC451
- Category
- Power Management
- Documents
- 2
- Languages
- EN
- Last added
- 2012-08-03
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Semtech SC4519H Step-Down Switching Regulator Datasheet
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.
Semtech SC451 specifications
| 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 |
Source: Semtech SC4519H Step-Down Switching Regulator Datasheet
All Semtech SC451 documents by type
Ratings, dimensions and ordering codes, for selection and design work.
Questions answered in these manuals
What is the operating frequency of the SC4519H?
The internal oscillator sets the PWM frequency at 600kHz without external components.
From: Semtech SC4519H Step-Down Switching Regulator Datasheet
What is the operating frequency range when using an external SYNC clock?
The regulator can synchronize to an external clock with a frequency between 700kHz and 1.2MHz.
From: Semtech SC4519H Step-Down Switching Regulator Datasheet
What is the function of the automatic power-save feature?
It prevents negative current flow in the low-side FET during light loading conditions to save more power.
From: Semtech SC451 Single Phase Power Supply Controller Datasheet
Is the SC451 backward compatible?
Yes, it is backward compatible with the SC1479.
From: Semtech SC451 Single Phase Power Supply Controller Datasheet