The LT3570 is a 1.5A buck converter, a 1.5A boost converter and an LDO controller, integrating power switches and LDO controllers. Each converter has a 1.5A current limit and an input range of 2.5V to 36V, making LT3570 ideal for a wide range of applications. Switching frequencies up to 2MHz are programmed with an external timing resistor and the oscillator can be synchronized to an external clock up to 2.75MHz. The LT3570 features a programmable soft-start function that limits the feedback voltage during start-up helping prevent overshoot and limiting inrush current. The LDO controller is capable of delivering up to 10mA of base current to an external NPN transistor.
The LT3570 is a buck and boost converter with an integrated LDO controller, offering up to 1.5 A current limit and an input voltage range of 2.5 V to 36 V. It is suited for applications such as cable set‑top boxes, automotive systems, telecom, TFT LCD displays, and other high‑performance power‑management needs.
The document provides electrical characteristics, pin descriptions, package options (24‑lead QFN and 20‑lead TSSOP), absolute maximum ratings, typical performance curves, and ordering information. Key features include programmable switching frequency (500 kHz‑2 MHz), synchronizable operation up to 2.75 MHz, soft‑start for each converter, and a 10 mA LDO output current.
| Input Voltage Range | 2.5 V to 36 V |
|---|---|
| Maximum Output Current | 1.5 A |
| Programmable Switching Frequency | 500 kHz to 2 MHz |
| Synchronizable Frequency | Up to 2.75 MHz |
| Duty Cycle Range | 0 % to 90 % at 1 MHz |
| LDO Output Current | 10 mA |
| Package Options | 24‑lead QFN (4 mm × 4 mm) and 20‑lead TSSOP |
The LT3570 operates with an input voltage from 2.5 V to 36 V.
The device can be programmed for switching frequencies between 500 kHz and 2 MHz, and can be synchronized up to 2.75 MHz.
It is available in a 24‑lead QFN (4 mm × 4 mm) package and a 20‑lead TSSOP package.
The shutdown current is specified as 15 pA typical.