LT1956

Input Voltage (VIN) ................................................. 60V
BOOST Pin Above SW ............................................ 35V
BOOST Pin Voltage ................................................. 68V
SYNC, SENSE Voltage (LT1956-5) ........................... 7V
SHDN Voltage ........................................................... 6V
BIAS Pin Voltage .................................................... 30V
FB Pin Voltage/Current (LT1956) ................... 3.5V/2mA
Operating Junction Temperature Range
LT1956EFE/LT1956EFE-5/LT1956EGN/LT1956EGN-5
(Notes 8, 10) ..................................... 40°C to 125°C
LT1956IFE/LT1956IFE-5/LT1956IGN/LT1956IGN-5
(Notes 8, 10) ..................................... 40°C to 125°C
Storage Temperature Range ............  65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C


Description

The LT®1956/LT1956-5 are 500kHz monolithic buck switching regulators with an input voltage capability up to 60V. A high efficiency 1.5A, 0.2W switch is included on the die along with all the necessary oscillator, control and logic circuitry. A current mode architecture provides fast transient response and good loop stability.

Special design techniques and a new high voltage process achieve high efficiency over a wide input range. Efficiency is maintained over a wide output current range by using the output to bias the circuitry and by utilizing a supply boost capacitor to saturate the power switch. Patented circuitry maintains peak switch current over the full duty cycle range*. A shutdown pin reduces supply current to 25mA and the device can be externally synchronized from 580kHz to 700kHz with a logic level input. 

The LT1956/LT1956-5 are available in fused-lead 16-pin SSOP and thermally enhanced TSSOP packages.