LTC3703EGN Linear Technology, LTC3703EGN Datasheet - Page 8

• Manufacturer Part Number: LTC3703EGN
• Description: IC BUCK/BOOST SYNC ADJ 5A 16SSOP
• Manufacturer: Linear Technology
• Type: Step-Down (Buck), Step-Up (Boost)r

Specifications of LTC3703EGN

• Internal Switch(s): No
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 0.8 ~ 93 V
• Current - Output: 5A
• Frequency - Switching: 100kHz ~ 600kHz
• Voltage - Input: 9.3 ~ 100 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-SSOP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Power - Output: -

LTC3703
FUNCTIONAL DIAGRAM
The LTC3703 is a constant frequency, voltage mode con-
troller for DC/DC step-down converters. It is designed to
be used in a synchronous switching architecture with two
external N-channel MOSFETs. Its high operating voltage
capability allows it to directly step down input voltages up
to 100V without the need for a step-down transformer. For
circuit operation, please refer to the Functional Diagram
OPERATION
8
R2
R1
V
C
CC
SS
C
16
12
VCC
5
1
3
4
MODE/SYNC
0.8V
RUN/SS
COMP
FB
V
3.2V
V
(<15V)
GN16
IN
CC
(Refer to Functional Diagram)
+
+
–
OVER
TEMP
OT SD
FB
0.9V
4μA
+
–
÷
DETECT
SYNC
UVSD OTSD
REFERENCE
BANDGAP
0.8V
% DC
LIMIT
EXT SYNC
FORCED CONTINUOUS
+
CHIP
SD
–
PWM
INTERNAL
3.2V V
OSC
0.76V
2
V
+
f
MIN
CC
SET
R
CC
–
SET
0.84V
+
MAX
–
UVLO
UV SD
of the IC and Figure 1. The LTC3703 uses voltage mode
control in which the duty ratio is controlled directly by
the error amplifi er output and thus requires no current
sense resistor. The V
feedback and is compared to the internal 0.8V reference
by the error amplifi er, which outputs an error signal at the
COMP pin. When the load current increases, it causes a
INV
OVERCURRENT
DRIVE
LOGIC
–
–
CURRENT
+
+
REVERSE
50mV
–
FB
±
+
12μA
pin receives the output voltage
±
BOOST
BGRTN
DRV
GND
INV
SW
INV
BG
TG
CC
15
14
13
11
10
5
9
6
8
I
MAX
V
CC
3703 FD
R
MAX
D
C
B
B
C
OUT
V
IN
L1
M1
M2
3703fb
V
OUT