XC9119D10A_1 Datasheet, PDF (8/18 Pages) Torex Semiconductor – 1MHz, PWM Controlled, Step-Up DC/DC Converter, Ceramic Capacitor Compatible

XC9119D10A Series
■TEST CIRCUITS
Circuit ①
CIN
VIN
4.7uF
(ceramic)
VCE
L:22uH
SD
CDRH4D18C XB01SB04A2BR
VOUT
VDD
CE/SS
VSS
Lx _CFB
1000pF
(ceramic)
FB
V
RFB1
300kΩ
CL
4.7uF
(ceramic)
RFB2
75kΩ
V
RL
Circuit ②
OSC
A
VIN
Rpull
Lx
CE
FB
220uF
VIN
VSS
1uF
VCE
VFB
Circuit ③
VIN
Vpull
A
VIN
Lx
A CE
FB A
VSS
1uF
VCE
VFB
A
VLx
Circuit ④
OSC
10 Ω 300Ω
100uF/16V
(OS capacitor)
10V
VIN
Lx
R2
CE
FB
4.3kΩ
Vpull
VIN
4.7uF/10V
VSS
(ceramic)
VCE
2SK583
R1
1.1kΩ
V
0.01uF
(ceramic)
47uF/25V
(OS capacitor)
1. The measurement method of Lx On resistance RSWON
Using the circuit ②, Lx On resistance can be measured by adjusting Vpull voltage to set Lx voltage VLx x 0.4V when the
driver transistor is ON. The oscilloscope is used for measuring the Lx voltage when the driver transistor is ON.
RSWON = 0.4 / {(Vpull – 0.4) / 10}
2. The measurement method of current limit ILIM
Using the circuit ④, current limit ILIM can be calculate by the equation including Vpull voltage when FB voltage is
decreased while Vpull voltage is adjusted and Lx voltage VLx when the driver transistor is ON. The oscilloscope is used
for measuring the Lx voltage when the driver transistor is ON.
ILIM=(Vpull – VLx) / Rpull
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