LT3645
36V 500mA Step-Down
Regulator and 200mA LDO
FEATURES DESCRIPTION n The LTВ®3645 is a dual output regulator combining a 500mA
buck regulator and a 200mA low dropout linear regulator (LDO). The wide input voltage range of 3.6V to 36V
makes the LT3645 suitable for regulating power from a
wide variety of sources, including 24V industrial supplies
and automotive batteries. Its high operating frequency
allows the use of tiny, low cost inductors and capacitors,
resulting in a very small solution. n n Wide Input Range:
Operation from 3.6V to 36V
Overvoltage Lockout Protects Circuit Through
55V Transients on Input
500mA Output Current Switching Regulator
High Switching Frequency: 750kHz
200mA Low Dropout Linear Regulator
1.2V to 16V Input; 0.8V to 8V Output
310mV Dropout Voltage VCC2 to OUT2
Precision Programmable Undervoltage Lockout
Short-Circuit Robust
Internal Soft-Start 1.23V, the LDO power transistor will turn on and
regulate the output at the OUT2 pin. An error amplifier
driving Q2 has its positive input at the 0.797V reference. …