Copyright © 2017, Texas Instruments Incorporated
C
SS
R
T
R
SYNC
R
ENT
R
ENB
SW
PVIN
PGND
CBOOT
VCC
BIAS
EN
AGND
FB
V
IN
C
OUT
C
BOOT
C
IN
C
VCC
V
OUT
R
FBT
R
FBB
L
SYNC/
MODE
RT
SS/TRK
PGOOD
VCC
RT
BIAS
SS/TRK
2
3
4
23
25
24
PVIN
SW
SW
DAP
PVIN
PGND
SW
22
26
1
5
CBOOT
SW
PGND
21
6
PGND
PGND
20
7
PGOOD
19
8
AGND
9
10
18
17
EN
FB
SYNC/
MODE
16
11
29
28
27
30
13
14
15
12
SW
PVIN
NC
NC
NC
NC
NC
NC
NC
NC
Introduction
2
SNVU579 – September 2017
Copyright © 2017, Texas Instruments Incorporated
LM73605 / LM73606 EVM User’s Guide
1
Introduction
1.1
LM73605 / LM73606 Synchronous Step-Down Voltage Converter
The LM73605/LM73606 family of devices are easy-to-use synchronous step-down DC-DC converters
capable of driving up to 5 A (LM73605) or 6 A (LM73606) of load current from a supply voltage ranging
from 3.5 V to 36 V. The LM73605/LM73606 provide exceptional efficiency and output accuracy in a very
small solution size. Peak-current-mode control is employed. Additional features such as adjustable
switching frequency, synchronization to an external clock, FPWM option, power-good flag, precision
enable, adjustable soft start, and tracking provide both flexible and easy-to-use solutions for a wide range
of applications. Automatic frequency foldback at light load and optional external bias improve efficiency
over the entire load range. The family requires few external components and has a pinout designed for
simple PCB layout with optimal EMI and thermal performance. Protection features include thermal
shutdown, input undervoltage lockout, cycle-by-cycle current limiting, and hiccup short-circuit protection.
The LM73605 and LM73606 devices are pin-to-pin compatible for easy current scaling.
The pin configuration of the LM73605/6 is shown in
and the schematic is shown in
for
your quick reference. See the
for more detailed feature descriptions and
design guide.
Figure 1. LM73605/6 Pin Configuration (30-Pin WQFN
Package Top View)
Figure 2. LM73605/6 Schematic
1.2
LM73605 / LM73606 Evaluation Module
The LM73605 / LM73606 EVM has three variants to cover a wide range of applications. The options
include LM73605 (5-A maximum DC output current) with 400-kHz switching frequency and 2.2-MHz
switching frequency, and LM73606 (6-A maximum DC output current) with 400-kHz switching frequency,
as listed in
. The output voltage is 5 V.
Table 2. EVM Variants
Label
U1
I
OUT
Switching
Frequency
V
IN
Range
V
OUT
LM73605EVM-5V-2MHz
LM73605
5 A
2.2 MHz
6 to 36 V
5 V
LM73605EVM-5V-400K
LM73605
5 A
400 kHz
6 to 36 V
5 V
LM73606EVM-5V-400K
LM73606
6 A
400 kHz
6 to 36 V
5 V