Datasheet

HG
BOOT
I
SEN
LG
PGND
FB
V
CC
SD
PWGD
FREQ/SYNC
SS/TRACK
SGND
EAO
PGND
V
CC
= 5V
V
IN
= 12V
V
OUT
= 3.3V@4A
R
FB2
C
C2
R
C1
R
CS
C
SS
R
CC
C
CC
D
1
C
BOOT
Q1
C
IN
1,2
L1
+
C
C1
R
FB1
C
O
1,2
LM2745
R
C2
C
C3
R
PULL-UP
R
FADJ
C
Clk
Clk
+
LM2745, LM2748
SNOSAL2E –APRIL 2005–REVISED APRIL 2013 www.ti.com
PART PART NUMBER TYPE PACKAGE DESCRIPTION VENDOR
U1 LM2745 Synchronous TSSOP-14 TI
Controller
Q1 FDS6898A Dual N-MOSFET SO-8 20V, 10 mΩ @ 4.5V, 16 nC Fairchild
D1 MBR0520LTI Schottky Diode SOD-123
L1 DO3316P-682 Inductor 6.8 µH, 4.4Arms, 27 mΩ Coilcraft
C
IN
1 16SP100M Aluminum 10mm x 6mm 100 µF, 16V, 2.89Arms Sanyo
Electrolytic
C
O
1 10SP56M Aluminum 6.3mm x 6mm 56 µF, 10V 1.7Arms Sanyo
Electrolytic
C
CC
, C
BOOT,
VJ1206Y104KXXA Capacitor 1206 0.1 µF, 10% Vishay
C
IN
2, C
O
2
C
C3
VJ0805Y182KXXA Capacitor 805 1800 pF, 10% Vishay
C
SS
VJ0805A123KXAA Capacitor 805 12 nF, 10% Vishay
C
C2
VJ0805A821KXAA Capacitor 805 820 pF 10% Vishay
C
C1
VJ0805A330KXAA Capacitor 805 33 pF, 10% Vishay
R
FB2
CRCW08051002F Resistor 805 10.0 kΩ 1% Vishay
R
FB1
CRCW08053161F Resistor 805 3.16 kΩ 1% Vishay
R
FADJ
CRCW08051003F Resistor 805 100 kΩ 1% Vishay
R
C2
CRCW08051301F Resistor 805 1.3 kΩ 1% Vishay
R
CS
CRCW08052101F Resistor 805 2.1 kΩ 1% Vishay
R
CC
CRCW080510R0F Resistor 805 10.0Ω 1% Vishay
R
C1
CRCW08053322F Resistor 805 33.2 kΩ 1% Vishay
R
PULL-UP
CRCW08051003J Resistor 805 100 kΩ 5% Vishay
C
CLK
VJ0805A560KXAA Capacitor 805 56 pF, 10% Vishay
Figure 35. 12V to 3.3V @ 4A, f
SW
= 300kHz
28 Submit Documentation Feedback Copyright © 2005–2013, Texas Instruments Incorporated
Product Folder Links: LM2745 LM2748