LTC3851A-1_15 Datasheet, PDF (30/30 Pages) Linear Technology – Synchronous Step-Down Switching Regulator Controller

LTC3851A-1
Typical Application
1.5V/15A Synchronized at 350kHz
PLLIN
C2
350kHz
0.01µF ^R5
1k
C1
1000pF
C_SS
0.1µF
R_C
C_C
1000pF
7.5k
C_C2
100pF
MODE/PLLIN V_IN
FREQ/PLLFLTR TG
RUN
BOOST
LTC3851A-1
TK/SS
SW
I_TH
INTV_CC
V_FB
BG
V_IN
6V TO 14V
C_B
0.1µF
+
M1
RJK0305DPB
C_IN
180µF
D_B
CMDSH-3
L1
0.68µH
R_SENSE
0.002Ω
4.7µF
M2
RJK0301DPB
1000pF
SENSE^–
SENSE⁺
GND
PGOOD
R_PG
V_PULL-UP
R22 10Ω
R20 10Ω
V_OUT
1.5V
C10
33pF
R2
43.2k
1%
+
15A
C_OUT
330µF
R1
×2
20k
1%
C_OUT: SANYO 2R5TPE330M9
L1: SUMIDA CEP125-OR6MC
3851A1 TA03
Related Parts
PART NUMBER
LTC3854
LTC3878
LTC3879
LTC3850/LTC3850-1
LTC3850-2
LTC3853
LTC3834/LTC3834-1
LT^®3845A
LTC3775
DESCRIPTION
Small Footprint Wide V_IN Range Synchronous Step-Down
DC/DC Controller
No R_SENSE™ Constant On-Time Synchronous Step-Down
DC/DC Controller
No R_SENSE Constant On-Time Synchronous Step-Down
DC/DC Controller
Dual 2-Phase, High Efficiency Synchronous Step-Down
DC/DC Controllers, R_SENSE or DCR Current Sensing and
Tracking
Triple Output, Multiphase Synchronous Step-Down DC/DC
Controller, R_SENSE or DCR Current Sensing and Tracking
Low I_Q, Synchronous Step-Down DC/DC Controller
Low I_Q , High Voltage Synchronous Step-Down DC/DC
Controller
High Frequency Synchronous Voltage Mode Step-Down
DC/DC Controller
COMMENTS
Fixed 400kHz Operating Frequency, 4.5V≤ V_IN ≤ 38V,
0.8V ≤ V_OUT ≤ 5.25V, 2mm × 3mm QFN-12
Very Fast Transient Response, t_ON(MIN) = 43ns, 4V≤ V_IN ≤ 38V,
0.8V ≤ V_OUT ≤ 0.9V_IN, SSOP-16
Very Fast Transient Response, t_ON(MIN) = 43ns, 4V≤ V_IN ≤ 38V,
0.6V ≤ V_OUT ≤ 0.9V_IN, MSOP-16E, 3mm × 3mm QFN-16
Phase-Lockable Fixed Operating Frequency 250kHz to 780kHz,
4V≤ V_IN ≤ 30V, 0.8V ≤ V_OUT ≤ 5.25V
Phase-Lockable Fixed Operating Frequency 250kHz to 750kHz,
4V≤ V_IN ≤ 24V, V_OUT Up to 13.5V
Phase-Lockable Fixed Operating Frequency 140kHz to 650kHz,
4V≤ V_IN ≤ 36V, 0.8V ≤ V_OUT ≤ 10V, I_Q = 30µA,
Adjustable Fixed Operating Frequency 100kHz to 500kHz,
4V≤ V_IN ≤ 60V, 1.23V ≤ V_OUT ≤ 36V, I_Q = 30µA, TSSOP-16
Synchronizable Fixed Frequency 250kHz to 1MHz, t_ON(MIN) = 30ns,
4V ≤ V_IN ≤ 38V, 0.6V ≤ V_OUT ≤ 0.8V_IN, MSOP-16E, 3mm × 3mm
QFN-16
30 Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ^● FAX: [phone] ^● www.linear.com
3851a1fa
LT 0511 REV A • PRINTED IN USA
 LINEAR TECHNOLOGY CORPORATION 2010