General Description
XC9120 Series is PWM, PWM/PFM auto/external switching controlled step-up DC/DC converter controller ICs.
Since maximum duty ratio is as large as 93%, the series is the best for the applications used as high step-up ratios, such as
the LCD panels and OLED. In this series, even if it is a high step-up ratio, the output voltage stabilized at high efficiency can
be obtained. With 0.9V (±2.0%) of reference voltage supply internal, and using external resistors, RFB1 and 2, output
voltage can be set up freely within a range of 1.5V to 30V. For a current sense, with the use of RSENSE, ceramic capacitors
can be used as load capacitors and allows for lower output ripple and reduced PCB area requirements.
Control automatically switches from PWM to PFM during light loads with the XC9121 series and the XC9122 series can
switch the control from PWM to PFM using external signals depending on the circuit conditions..
During stand-by (when the CE pin is low), all circuits are shutdown to reduce current consumption to as low as 1.0μA or less.
The overcurrent limit circuit of this IC is designed to monitor the ripple voltage of the FB pin and operates the IC to stop when
the ripple voltage runs over 250mV. The IC resumes its operation with a toggle of the CE pin or by turning the power supply
back on.
Features
- Input Voltage Range : 0.9V~6.0V
- Operating Voltage Range : 1.8V~6.0V
- Output Voltage Range : 1.5V~30V (externally set)
Reference voltage 0.9V (±2.0%)
- Oscillation Frequency : 100kHz (±15%)
- Output Current : ≥80mA (VIN=3.6V, VOUT=15V)*
Applications
- Power Supply for the LCDs.
- High Step-Up Ratio Equipment (OLED, etc.)
Typical Application Circuit
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