General Description
The XC9111 series is a group of PFM controlled step-up DC/DC converter/controller ICs designed to generate low supply
voltage by the combination of PFM control and CMOS structure. The series is ideal for applications where a longer battery life is
needed such as in portable communication equipment. With a built-in 2.5ΩN-channel driver transistor, the XC9110A/C/E and
XC9111A/C/E types provide a step-up operation by using only a coil, a capacitor, and a diode connected externally.
The XC9110/9111B, D and F versions can be used with an external transistor for applications requiring larger currents.
Output voltage is internally programmable in a range from 1.5V to 7.0V in increments of 100mV (accuracy:±2.5%).
Maximum oscillation frequency is set to 100kHz for XC9110/9111 series. (At light loads, it is set to 180kHz for the XC9111
series.) Options include products equipped with a CE pin (C and D versions) that allows the IC to be shut down thereby
reducing supply current and with separated VDD/VOUT pins (E and F versions) to separate the power supply block and the
output voltage detect block. With the XC9110 series, maximum duty cycle is set to 75% (VDD=3.3V) making it suitable for
use with large current operations. The XC9111 series automatically switches duty ratio between 56% & 75% (VDD=3.3V)
when it senses changes in load to drop output ripple voltage and can support both large and small currents. The external
transistor types (B/D/F types) can be provided for applications, which require larger currents.
Features
- Operating (Input) Voltage Range : 0.9V ~ 10.0V
- Output Voltage Range : 1.5V~7.0V (100mV increments,
accuracy ±2.5%)
- Maximum Oscillation Frequency: 100kHz (accuracy ±15%)
- Built-in Switching N-ch Transistor: A/C/E type
- External Transistor Types : B/D/F type
- Lx Limit Voltage : E type: more than VDD=2.0V
A/C type: more than VOUT=2.0V
- Low Supply Current : 2.0μA
Applications
- Mobile phones
- Various palm top equipment
- Cameras, VCRs
- Various portable equipment
Typical Application Circuit
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