LTC3122_15 Datasheet, PDF (17/26 Pages) Linear Technology – 15V, 2.5A Synchronous Step-Up DC/DC Converter with Output Disconnect

Applications Information
LTC3122
V_IN
5V
C_IN
4.7µF
L1
3.3µH
OFF ON
SW
V_IN
V_OUT
LTC3122
SD
BURST PWM PWM/SYNC
CAP
RT
FB
R_T
57.6k
V_CC
SGND
V_C
PGND
C_VCC
4.7µF
C1
100nF
R_C
210k
C_C
390pF
R1
1.02M
R2
113k
C_F
10pF
V_OUT
12V
800mA
C_OUT
22µF
3122 F05a
Switching Waveforms with 800mA Load
V_OUT
100mV/DIV
AC-COUPLED
SW
10V/DIV
INDUCTOR
CURRENT
1A/DIV
200ns/DIV
3122 F05b
Transient Response with 400mA
to 800mA Load Step
V_OUT
500mV/DIV
AC-COUPLED
OUTPUT
CURRENT
500mA/DIV
100µs/DIV
3122 F05c
Figure 5. 1MHz, 5V to 12V, 800mA Boost Converter
170
150
130
110
90
70
50
30
10
–10
–30
0.01
180
140
PHASE
100
60
20
–20
–60
GAIN
–100
–140
–180
–220
0.1
1
10
100 1000
FREQUENCY (kHz)
3122 F06
Figure 6. Bode Plot for Example Converter
For more information www.linear.com/LTC3122
3122fa
17