Part Number |
LM3351 |
Manufacturers |
National Semiconductor |
Logo |
|
Description |
Switched Capacitor Voltage Converter |
Datasheet |
LM3351 Datasheet (PDF) |
LM3351 Switched Capacitor Voltage Converter
December 1999
LM3351 Switched Capacitor Voltage Converter
General Description
The LM3351 is a CMOS charge-pump voltage converter which efficiently provides a 3.3V to 5V step-up, or 5V to 3.3V step-down. The LM3351 is pin for pin compatible with the LM3350 but consumes 66% less quiescent current. The LM3351 uses four small, low cost capacitors to provide the voltage conversion. It eliminates the cost, size and radiated EMI related to inductor based circuits, or the power loss of a linear regulator. Operating power conversion efficiency greater than 90% provides ideal performance for battery powered portable systems. The architecture provides a fixed voltage conversion ratio of 3/2 or 2/3. Thus it can be used for other DC-DC conversions as well. n n n n n 4.2Ω typical step-up output impedance 1.8Ω typical step-down output impedance 95% typical power conversion efficiency at 50 mA 250 nA typical shutdown current Low quiescent current extends b.