LTC3545 LINER [Linear Technology], LTC3545 Datasheet - Page 17

• Manufacturer Part Number: LTC3545
• Description: Triple 800mA Synchronous Step-Down Regulator-2.25MHz
• Manufacturer: LINER [Linear Technology]

TYPICAL APPLICATIONS
2.7V TO 5.5V
V
IN
100
90
80
70
60
50
40
30
20
10
PGOOD2
0
0.1
T
V
V
f
CHANNEL 2 = 1.2V, I
CHANNEL 3 = 1.5V, I
OSC
E2
A
IN
OUT
= 25°C
= 3.6V
CHANNEL 1 LOAD CURRENT (mA)
= 2.25MHz
Channel 1 Load Current
= 2.5V
Overall Effi ciency vs
PGOOD1
R2
511k
1
E1
C1
10μF
10V
LOAD
LOAD
10
R1
511k
= 400mA
= 400mA
100
Figure 4. LTC3545 Low Ripple Burst Mode Operation
1
2
3
4
5
6
7
8
3545 TA03
1000
SW1
PGOOD1
RUN2
PGOOD2
SW2
PGND
P
SW3
VIN
LTC3545
GND
SYNC/MODE
17
GNDA
RUN1
RUN3
V
V
V
V
FB1
FB2
FB3
IN
16
15
14
13
12
11
10
9
AC COUPLED
250mA/DIV
20mV/DIV
C5
4.7μF
2V/DIV
V
OUT3
SW3
I
L3
T
V
V
I
f
LOAD
OSC
A
IN
OUT
= 25°C
1.5μH
1.5μH
1.5μH
= 3.6V
LTC3545/LTC3545-1
= 2.25MHz
L1
L2
L3
= 1.5V
20pF
20pF
20pF
= 50mA
C6
C7
C8
Burst Mode Ripple
1μs/DIV
R3
191k
R4
60.4k
R5
100k
R6
100k
R7
165k
R8
110k
3545 TA02
C3
10μF
6.3V
C2
10μF
6.3V
C4
10μF
6.3V
3545 TA04
E3
V
E4
GND
E7
V
E6
GND
E5
V
E8
GND
OUT1
OUT2
OUT3
2.5V AT 0.8A
1.2V AT 0.8A
1.5V AT 0.8A
17
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