XC9103/XC9104/XC9105 Series
■TYPICAL APPLICATION CIRCUIT
When obtaining VDD from a source other than VOUT,
please insert a capacitor CIN between the VDD pin and the
GND pin in order to provide stable operations.
Insert RB and CB when using a bipolar
NPN Transistor.
Please place CL and CIN as close as to the VOUT and VDD
pins respectively and also close to the GND pin.
Strengthen the wiring sufficiently. RSENSE should be
removed and shorted when the CL capacitor except for
ceramic or low ESR capacitor is used.
■NOTES ON USE
SCE
ON
SPWM
－
CONDITIONS
Chip Disable
OFF
OFF
ON
Duty=25%, PWM/PFM automatic switching
PWM
OFF
By using external signals, the control of the XC9105 series can be
alternated between PWM control and PWM/PFM automatic switching
control. By inputting a voltage of more than VDD -0.2V to the CE/PWM
pin, PWM control can be selected. On the other hand, PWM/PFM
automatic switching control can be selected by inputting a voltage of less
than VDD -1.0V.
With the XC9105, by connecting resistors of the same value (RM1, RM2) as
shown in the diagram to the left, it is possible to obtain chip disable with
SCE ON and, SPWM ON or OFF, PWM/PFM auto switching at Duty=25%
with SCE OFF & SPWM ON, & PFM control with both switches OFF.
Note:
When operating at VDD -1.8V and below (stepping-up from VIN=0.9V), it is
necessary to pull-up to VDD in order to allow the CE/PWM pin reach the
VCEH voltage level. Please make sure that the IC is in PWM control
(SPWM=OFF) when operations start. If SPWM is ON, there are times when
chip enable might not operate.
* Please select your external components carefully.
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TOREX [ Torex Semiconductor ]
