LTC3124_15 Datasheet, PDF (21/28 Pages) Linear Technology – 15V, 5A 2-Phase Synchronous Step-Up DC/DC Converter with Output Disconnect

APPLICATIONS INFORMATION
LB
4.7µH
V_IN
5V
SWB
CAP
LA
4.7µH
PGNDB V_OUTB
SWA
V_OUTA
LTC3124
PGNDA
C1
100nF
C_OUT
22µF
×2
V_OUT
12V
1.5A
V_IN
SGND
BURST PWM
C_IN
10µF
PWM/SYNC SD
V_CC
FB
RT
V_C
C_VCC
4.7µF
R_T
28k
C_C
680pF
C1: 100nF, 16V, X5R, 0805
C_IN: 10µF, 10V, X5R, 1206
C_OUT: 22µF ×2, 16V, X5R, 1210
C_VCC: 4.7µF, 10V, X5R, 1206
LA, LB: COILCRAFT XAL5030-472ME
OFF ON
R_C
84.5k
C_F
56pF
R1
1.02M
R2
113k
3124 F08
Figure 8. 1MHz, 5V to 12V, 1.5A Boost Converter
LTC3124
Switching Waveforms with 1.5A Load
V_OUT
20mV/DIV
AC-COUPLED
V_SWB
10V/DIV
V_SWA
10V/DIV
INDUCTOR B
CURRENT
1A/DIV
INDUCTOR A
CURRENT
1A/DIV
200ns/DIV
3124 F08b
Transient Response with 700mA to 1.5A Load Step
V_OUT
500mV/DIV
AC-COUPLED
OUTPUT
CURRENT
500mA/DIV
700mA
1500mA
100µs/DIV
700mA
3124 F08c
45
90
30
15
GAIN
0
45
PHASE
0
–45
–15
–90
–30
–135
–45
100
1k
10k
FREQUENCY (Hz)
–180
100k
3124 F09
Figure 9. Bode Plot for Example Converter
For more information www.linear.com/LTC3124
3124f
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