LTC3736-1 Datasheet, PDF (24/28 Pages) Linear Technology – Dual 2-Phase, No RSENSE Synchronous Controller with Spread Spectrum

LTC3736-1
TYPICAL APPLICATIO S
V_IN
3.3V
C_IN
22µF
68pF
R_FB1A
59k
R_FB1B
187k
C_ITH1A
47pF
22
SW1
SENSE1^{+ 21}
MP1
C_ITH1
470pF
R_ITH1
22k
2200pF
23
24
1
2
3
IPRG1
V_FB1
I_TH1
IPRG2
FREQ
PGND ²⁰
BG1 ¹⁹
SSDIS
TG1
PGND
18
17
16
4 _SGND
TG2 ¹⁵
R_VIN 10Ω
5 _VIN
RUN/SS ¹⁴
LTC3736EUF-1 ₁₃
C_ITH2
C_{VIN 470pF}
1µF
R_ITH2
22k
9
7
8
6
PGOOD
V_FB2
I_TH2
TRACK
BG2
PGND
SENSE2⁺
12
11
SW2 ¹⁰
PGND
MP2
C_SS
10nF
C_ITH2A
25
47pF
MN1
Si7540DP
L1
1.5µH
V_OUT1
2.5V
2A
C_OUT1
100µF
MN2
Si7540DP
L2
1.5µH
C_OUT2
100µF
V_OUT2
1.8V
2A
R_FB2A
59k
R_TRACKA ^RFB2B R_TRACKB
590Ω ^118k 1.18k
100pF
L1, L2: VISHAY IHLP-2525CZ-01
C_OUT1, C_OUT2: MURATA GRM32EROJ107M
37361 F14
Figure 14. 2-Phase, Spread Spectrum, Dual Output Synchronous DC/DC Converter with Ceramic Output Capacitors
Efficiency vs Load Current
100
Load Step
90
V_OUT
80
AC-COUPLED
100mV/DIV
70
60
50
40
I_L
1A/DIV
30
20
10
V_OUT = 2.5V
0
V_OUT = 1.8V
1
10
100
1000 10000
LOAD CURRENT (mA)
100µs/DIV
V_OUT = 2.5V
I_LOAD = 100mA TO 1A
37361 F14b
Load Step
V_OUT
AC-COUPLED
50mV/DIV
37361 F14c
I_L
1A/DIV
100µs/DIV
V_OUT = 1.8V
I_LOAD = 100mA TO 1A
37361 F14d
37361f
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