The KF9105 series is a CMOS step-up switching regulator which mainly consists of a reference voltage source, an oscillation circuit, an error amplifier, a phase compensation circuit, a PWM/PFM switching control circuit. With an external low-ON-resistance Nch Power MOS, this product is applicable to applications requiring high efficiency and high output current.The KF9105 series switches its operation to the PFM control circuit whose duty ratio is 15 % with to the PWMPFM switching control circuit under a light load and to prevent decline in the efficiency by IC operation current.
Features
Low voltage operation: Start-up is guaranteed from 0.9 V(lout =1 mA )
Efficiency: 90%
Duty ratio: Buit-in PWM/PFM switching control
circuit 15 to 78 % .
oscillator frequency: 1.0MHz
External parts: coil, diode， capacitor, and transistor
Output voltage range: 1.5V -6.5 V
Output voltage accuracy: +2%
Soft start function: 2 mS.
PACKAGE: SOT23-5
Typical Application
lphone, IPAD, mobile back-up power
MP3 players, digital audio players
Digital cameras, GPS, wireless transceiver
Portable devices