The LT1300 is a micropower step-up DC/DC converter that utilizes Burst Mode™ operation. The device can deliver 5V or 3.3V from a two-cell battery input. It features program- mable 5V or 3.3V output via a logic-controlled input, no- load quiescent current of 120µA and a shutdown pin which reduces supply current to 10µA. The on-chip power switch has a low 170mV saturation voltage at a switch current of 1A, a four-fold reduction over prior designs. A 155kHz internal oscillator allows the use of extremely small sur- face mount inductors and capacitors. Operation is guaran- teed at 1.8V input. This allows more energy to be extracted from the battery increasing operating life. The ILIM pin can be used to program peak switch current with a single resistor allowing the use of less expensive and smaller inductors and capacitors in lighter load applications. The LT1300 is available in an 8-lead SOIC package, minimizing board space requirements. For a 5V/12V output, the LT1300 can be used with two AA batteries or a single AAA battery.
The LT1300 is a micropower high‑efficiency step‑up DC/DC converter that can generate a regulated 3.3 V or 5 V output from a low‑voltage supply as low as 1.8 V. It features a programmable output selector, a shutdown pin that reduces quiescent current to 10 pA, and a low‑voltage switch with a typical saturation of 170 mV at 1 A.
Typical applications include palmtop computers, portable instruments, barcode scanners, PCMCIA cards and battery‑backup supplies. The device is offered in an 8‑lead SOIC or DIP package, and its pin functions (GND, SELECT, SHDN, SENSE, ILIM, VIN, SW, PGND) are described for easy board layout.
| Maximum Output Current (5 V) | 220 mA |
|---|---|
| Efficiency | up to 88 % |
| Minimum Input Voltage | 1.8 V |
| Shutdown Current | 10 pA |
| Output Voltage (5 V mode) | 5.0 V (typical) |
| Output Voltage (3.3 V mode) | 3.3 V (typical) |
The device can deliver up to 220 mA of output current at 5 V.
The LT1300 operates with an input voltage as low as 1.8 V.
The SELECT pin (pin 2) sets the output: high for 5 V, low for 3.3 V, or it can be tied to ground or VCC for a fixed voltage.
Activating the SHDN pin reduces quiescent current to about 10 pA.