LTC1174-5

Features:

High Efficiency: Up to 94%
Peak Inductor Current Independent of Inductor Value
Short-Circuit Protection
Optimized for 5V to 5V Applications
Wide V_IN Range: 4V to 18.5V
Low Dropout Operation
Low-Battery Detector
Pin Selectable Current Limit
Internal 0.9? Power Switch: V_IN = 9V
Only Four External Components Required 130A Standby Current
Active Low Micropower Shutdown


Application

Distributed Power Systems
Step-Down Converters
Inverting Converters
Memory Backup Supply
Portable Instruments
Battery-Powered Equipment


Pinout




Specifications

(Voltage Referred to GND Pin)
Input Supply Voltage (Pin 6)
LTC1174 ................................................ 0.3V to 13.5V
LTC1174HV  ............................................0.3V to 18.5V
Switch Current (Pin 5) ............................................... 1A
Switch Voltage (Pin 5)
LTC1174 ...................................................  V_IN  13.5V
LTC1174HV  ..............................................  V_IN  18.5V
Operating Temperature Range ................ 0°C to 70°C
Extended Commercial
Temperature Range  ........................... 40°C to 85°C
Junction Temperature (Note 1)............................ 125°C
Storage Temperature Range.............. 65°C to 150°C
Lead Temperature (Soldering, 10 sec)..................300°C



Description

The LTC_(R) 1174 is a simple current mode DC/DC converter ideally suited for 9V to 5V, 5V to 3.3V, or 5V to 5V operation. With an internal 0.9? switch (at a supply voltage of 9V), the LTC1174 requires only four external components to construct a complete high efficiency DC/DC converter.

Under a no load condition the LT1174 draws only 130A. In shutdown, it draws a mere 1A making this converter ideal for current sensitive applications. In dropout, the internal P-channel MOSFET switch is turned on continu- ously allowing the user to maximize the life of the battery source.

The maximum inductor current of the LTC1174 family is pin selectable to either 340mA or 600mA, optimizing efficiency for a wide range of applications. Operation up to 200kHz permits the use of small surface mount inductors and capacitors.

For applications requiring higher output current or ultra- high efficiency, see the LTC1148 data sheet.