LTC1701 LINER [Linear Technology], LTC1701 Datasheet - Page 3

• Manufacturer Part Number: LTC1701
• Description: 1MHz Step-Down DC/DC Converter in SOT-23
• Manufacturer: LINER [Linear Technology]

PI FU CTIO S
SW (Pin 1): The Switch Node Connection to the Inductor.
This pin swings from V
voltage drop below ground. The cathode of the Schottky
diode must be closely connected to this pin.
GND (Pin 2): Ground Pin. Connect to the (–) terminal of
C
V
external resistive divider across the output. Nominal volt-
age for this pin is 1.25V.
Pin Limit Table
PIN
1
2
3
4
5
BLOCK DIAGRA
I
OUT
FB
TH
U
/RUN
V
(Pin 3): Receives the feedback voltage from the
, the Schottky diode and (–) terminal of C
FB
V
V
REF
REF
U
NAME
SW
GND
V
I
V
TH
FB
IN
/RUN
–
–
+
+
ERROR
1.4V
I
CLAMP
TH
AMP
/REF
U
+
–
VOLTAGE
COMP
IN
OVER
to a Schottky diode (external)
W
DESCRIPTION
Switch Node
Ground Pin
Output Feedback Pin
Error Amplifier Compensation and RUN Pin
Main Power Supply
V
IN
50 A
(1.25V TO 2.25V)
SHDN
STRETCHER
V
FB
PULSE
< 0.6V
IN
1.5V
.
REFERENCE
BANDGAP
1.25V
V
IN
–
+
COMP
I
TH
I
sation Point and Run Control Input. The current compara-
tor threshold increases with this control voltage. Nominal
voltage range for this pin is 1.25V to 2.25V. Forcing this
pin below 0.8V causes the device to be shut down. In
shutdown all functions are disabled.
V
Current Comparator. Must be closely decoupled to ground.
TH
IN
/RUN (Pin 4): Combination of Error Amplifier Compen-
(Pin 5): Main Supply Pin and the (+) Input to the
V
(1.25V)
REF
– 0.3
MIN
2.5
0
0
NOMINAL (V)
CURRENT
COMP
1.25
TYP
0
+
–
CONTROL LOGIC
OFF-TIMER
MAX
V
AND GATE
1.35
2.25
V
5.5
REF
IN
– 0.3
– 0.3
– 0.3
– 0.3
MIN
ABSOLUTE MAX (V)
CURRENT
SENSE
AMP
LTC1701
DRIVER
GATE
–
+
GND
V
V
IN
IN
MAX
+ 0.3
3
3
6
1701 BD
3
SW