特点
Synchronous Rectification: Up to 97% Efficiency
1A Switch Current Rating
Fixed Frequency Operation Up to 3MHz
Wide Input Range: 0.5V to 5V (Operating)
Very Low Quiescent Current: 38μA (Burst Mode? Operation)
2.6V to 5V Adjustable Output Voltage
0.85V (Typ) Start-Up Voltage
No External Schottky Diode Required (V
OUT
< 4.3V)
Synchronizable Switching Frequency
Burst Mode Enable Control
Antiringing Control Reduces Switching Noise
PGOOD Output
OPTI-LOOP
?
Compensation
Very Low Shutdown Current: <1μA
Small 10-Pin MSOP Package
典型应用
典型应用
描述
The LTC?3401 is a high efficiency, fixed frequency, step-up DC/DC converter that operates from an input voltage below 1V. The device includes a 0.16 Ohms N-channel MOSFET switch and a 0.18 Ohms P-channel synchronous rectifier. Switching frequencies up to 3MHz are programmed with an external timing resistor and the oscillator can be synchronized to an external clock. An external Schottky diode is optional but will slightly improve efficiency.
Quiescent current is only 38μA in Burst Mode operation, maximizing battery life in portable applications. Burst Mode operation is user controlled and can be enabled by driving the MODE/SYNC pin high. If the MODE/SYNC pin has either a clock or is driven low, then fixed frequency switching is enabled.
Other features include 1μA shutdown, antiringing control, open-drain power good output, thermal shutdown and current limit. The LTC3401 is available in the 10-lead thermally enhanced MSOP package. Higher current applications should use the 2A rated LTC3402 synchronous boost converter. Applications that require V OUT < 2.6V should use the LTC3423.