LM1770 #3: 2.5V @ 3A, 5V in, (Page 7)

Summary

The controller utilizes a constant on-time control scheme which eliminates the need for external compensation components, allowing the power supply designer to minimize necessary board space and reduce costs.

The use of a small valued inductor (1.5 µH) is made possible by the high frequency operation. A 68 µF, low profile, POSCAP output capacitor is used, along with a 10 nF ceramic feed-forward capacitor, to ensure stability. The 500 ns LM1770 timing option allows for the 1.5 MHz switching frequency.

Specifications

Manufacturer	Texas Instruments
Category	AC/DC and DC/DC Conversion
Sub-Category	DC/DC SMPS - Single Output
Eval Board	Board not Stocked
Topology	Step Down
Outputs and Type	1 Non-Isolated
Voltage Out: Factory Set	2.5 V
Current Out	3 A
Voltage In	5 V
Efficiency @ Conditions	>84%, 5V in, 2.5V @ 0.8 ~ 3 A
Voltage Out Range
Features	Short Circuit Protection Soft Start
Switching Frequency	1.5 MHz
Standby Current [Typical]
Quiescent Current [Typical]	400 µA
Component Count + Extras	9 + 0
Internal Switch	No
Design Author	Texas Instruments
Application / Target Market	Computers DVD/Blu-ray Players Point of Load (PoL) Portable Devices Set-Top Boxes Telecom USB Powered Devices White Goods
Standby Current [Maximum]
Quiescent Current [Maximum]	600 µA
Main I.C. Base Part	LM1770S
Date Created By Author
Date Added To Library	2020-05