LTC3729_15 Datasheet, PDF (30/30 Pages) Linear Technology – 550kHz, PolyPhase, High Efficiency, Synchronous Step-Down Switching Regulator

LTC3729
TYPICAL APPLICATION
13.2k
0.1µF
3.3k 33pF
16.5k
100pF
1000pF
1000pF
1
28
2
3
4
RUN/SS
SENSE1⁺
SENSE1^–
CLKOUT ₂₇
TG1 ₂₆
SW1 ₂₅
5 ^EAIN
BOOST1 ₂₄
6 ^PLLFLTR
V_{IN 23}
7 ^PLLIN
8 ^PHASMD
BG1
EXTV_CC
22 _5V
21
9 ^ITH
10 ^SGND
LTC3729
INTV_CC
PGND
20
19
11
12
13
14
V_DIFFOUT
V_OS–
V_OS+
SENSE2^–
SENSE2⁺
BG2 ₁₈
BOOST2 ₁₇
SW2 ₁₆
TG2 ₁₅
PGOOD
1000pF
0.47µF
D3
1µF,6.3V
L1
0.003Ω
M1
10Ω
0.1µF
4.7µF
6.3V
M2
C_IN
D1
UPS840
C_OUT
D4
100k
0.47µF
POWER
GOOD
M3
L2
D2
UPS840
M4
0.003Ω
V_IN
6V TO
16V
V_OUT
3.3V/30A
V_IN: 5V TO 16V
V_OUT: 3.3V/30A
SWITCHING FREQUENCY = 250kHz
MI, M3: IRF7811
M2, M4: IRF7809
L1, L2: 1µH SUMIDA CEP125-1R0MC-H
C_IN: OS CON 2-16SP270M
C_OUT: KEMET 3-T510 470mF
D3, D4: CENTRAL CMDSH-3TR
Figure 12. 3.3V/30A Power Supply with Active Voltage Positioning
3729TA02
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PART NUMBER
DESCRIPTION
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Triple Output, Multiphase Synchronous Step-Down DC/DC
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COMMENTS
PLL Fixed 250kHz to 770kHz Frequency, 4.5V ≤ V_IN ≤ 38V,
0.8V≤ V_OUT ≤ 5V
I²C/PMBus Interface with EEPROM and 16-Bit ADC, V_IN Up to 24V,
0.5V ≤ V_OUT ≤ 5.5V, Analog Control Loop
PLL Fixed 250kHz to 770kHz Frequency, 4.5V ≤ V_IN ≤ 38V,
0.8V ≤ V_OUT ≤ 5V
PLL Fixed 250kHz to 750kHz Frequency, 4V ≤ V_IN ≤ 38V,
V_OUT3 Up to 12.5V
PLL Fixed 250kHz to 780kHz Frequency, 4V ≤ V_IN ≤ 30V,
0.8V ≤ V_OUT ≤ 5.25V
PLL Fixed Frequency 250kHz to 770kHz, 4.5V ≤ V_IN ≤ 38V,
0.8V ≤ V_OUT ≤ 12V
PLL Fixed 250kHz to 750kHz Frequency, 4V ≤ V_IN ≤ 24V,
V_OUT3 Up to 13.5V
Operates with Power Blocks, DRMOS Devices or External
MOSFETs 3V ≤ V_IN ≤ 24V, t_ON(MIN) = 20ns
Phase-Lockable Fixed Operating Frequency 50kHz to 900kHz,
4V ≤ V_IN ≤ 38V, 0.8V ≤ V_OUT ≤ 24V, I_Q = 50µA
30 Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ^● FAX: [phone] ^● www.linear.com
3729fb
0311 REV B • PRINTED IN USA
 LINEAR TECHNOLOGY CORPORATION 2001