XC9116B02ADL TOREX [Torex Semiconductor], XC9116B02ADL Datasheet - Page 5

• Manufacturer Part Number: XC9116B02ADL
• Description: Step-Up DC/DC Converter-Backlight LED Driver
• Manufacturer: TOREX [Torex Semiconductor]

■TYPICAL APPLICATION CIRCUITS
■EXTERNAL COMPONENTS
■OPERATIONAL EXPLANATION
●XC9116B02A
NOTE :
The series consists of a reference voltage source, ramp wave circuit, error amplifier, PWM comparator, phase
compensation circuit, Lx overvoltage limit circuit, N-channel MOS driver transistor, current limiter circuit and others. The
series ICs compare, using the error amplifier, the voltage of the internal voltage reference source with the feedback
voltage from the FB pin. Phase compensation is performed on the resulting error amplifier output, to input a signal to the
PWM comparator to determine the turn-on time during switching. The PWM comparator compares, in terms of voltage
level, the signal from the error amplifier with the ramp wave from the ramp wave circuit, and delivers the resulting output
to the N-channel MOS driver transistor to cause the Lx pin to output a switching duty cycle. This process is continuously
performed to ensure stable output voltage. The current feedback circuit detects the N-channel MOS driver transistor's
current for each switching operation, and modulates the error amplifier output signal. This enables a stable feedback
loop even when a low ESR capacitor, such as a ceramic capacitor, is used, ensuring stable output voltage.
<Reference Voltage Source>
<Ramp Wave Circuit>
<Error Amplifier>
The error amplifier is designed to monitor output voltage. The amplifier compares the reference voltage with the FB pin
voltage. When a voltage lower than the reference voltage is fed back, the output voltage of the error amplifier
increases. Gain and frequency characteristics of the error amplifier output are fixed internally as an optimize signal.
The reference voltage source provides the reference voltage to ensure stable output voltage of the IC.
The ramp wave circuit determines switching frequency. The 1MHz (TYP.) of frequency is fixed internally.
Clock pulses generated in this circuit are used to produce ramp waveforms needed for PWM operation.
*1: Please use a Schottky
*2: For using the XB0ASB03A1BR with four white LEDs in series, please be noted with a direct reverse voltage (V
*3: Use ceramic capacitors processing a low temperature coefficient.
*4: Please refer to the LED Open-circuit Protection at Application Information for setting the Zener diode.
SYMBOL
SBD (*1)
ZD (*4)
repetitive peak reverse voltage (V
CL (*3)
C
R1
L
IN
VALUE
0.22µF
100 Ω
4.7µF
barrier diode (SBD) with a low junction capacitance, Cj.
22µH
18V
-
RM
=30V).
XB0ASB03A1BR (*2)
JMK107BJ475MA-B
TMK107BJ224KA-B
VLF3010A-220MR
PART NUMBER
●XC9116D02A
MA2Z720
MAZ8180
-
MANUFACTURER
TAIYO YUDEN
TAIYO YUDEN
PANASONIC
PANASONIC
TOREX
TDK
-
R
=20V) and a
XC9116
Series
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