The following content is an automatically extracted verbatim text
from the original manufacturer datasheet and is provided for reference purposes only.
View original datasheet text
700mA SmartLDO
TM
SC1537
PRELIMINARY - July 25, 2000
TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.semtech.com
DESCRIPTION
The SC1537 is designed to maintain a glitch-free 3.3V output when at least one of two inputs, 5V (VIN) and 3.3V (VAUX), is present. Whenever VIN exceeds a predetermined threshold value, the internal 3.3V linear regulator is enabled, and DR is pulled high. When VIN falls below a lower threshold value, DR is pulled low and the internal linear regulator is turned off. DR has been designed to drive the gate of an external low threshold P-channel MOSFET, which can be used to connect the 3.3V supply directly to the regulator output. This ensures an uninterrupted 3.3V output even if VIN falls out of specification. A maximum RDS(ON) of 100mΩ is recommended.