LTC3611EWP LINER [Linear Technology], LTC3611EWP Datasheet - Page 8

• Manufacturer Part Number: LTC3611EWP
• Description: 10A, 32V Monolithic Synchronous Step-Down DC/DC Converter
• Manufacturer: LINER [Linear Technology]

PIN FUNCTIONS
LTC3611
PGND (Pins 1, 2, 3, 56, 57, 58, 59, 60, 61, 62, 63, 64,
65): Power Ground. Connect this pin closely to the (–)
terminal of C
SW (Pins 4, 5, 6, 7, 8, 9, 10, 11, 26, 55, 66): Switch
Node Connection to the Inductor. The (–) terminal of the
bootstrap capacitor C
from a diode voltage drop below ground up to V
PV
23, 24, 25, 67): Main Input Supply. Decouple this pin to
power PGND with the input capacitance C
NC (Pin 27): No Connection.
SGND (Pins 28, 31, 32, 33, 34, 40, 42, 45, 46, 47, 48,
49, 50, 68): Signal Ground. All small-signal components
and compensation components should connect to this
ground, which in turn connects to PGND at one point.
BOOST (Pin 29): Boosted Floating Driver Supply. The
(+) terminal of the bootstrap capacitor C
This pin swings from a diode voltage drop below INTV
up to V
RUN/SS (Pin 30): Run Control and Soft-Start Input. A
capacitor to ground at this pin sets the ramp time to full
output current (approximately 3s/μF) and the time delay
for overcurrent latchoff (see Applications Information).
Forcing this pin below 0.8V shuts down the device.
V
for the on-time comparator. Tying this pin to the output
volt-age or an external resistive divider from the output
makes the on-time proportional to V
tor input defaults to 0.7V when the pin is grounded and
defaults to 2.4V when the pin is tied to INTV
pin to INTV
R
PGOOD (Pin 36): Power Good Output. Open drain logic
output that is pulled to ground when the output voltage
is not within ±10% of the regulation point.
8
ON
ON
IN
(Pin 35): On-Time Voltage Input. Voltage trip point
value.
(Pins 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
IN
+ INTV
CC
VCC
in high V
CC
and the (–) terminal of C
.
B
also connects here. This pin swings
OUT
applications to use a lower
OUT
B
. The compara-
IN
connects here.
IN
.
.
CC
. Tie this
IN
.
CC
V
at this pin adjusts maximum valley current and can be
set from 0.7V to 1V by a resistive divider from INTV
It defaults to 0.7V if the V
results in a typical 10A current limit.
I
Compensation Point. The current comparator threshold
increases with this control voltage. The voltage ranges
from 0V to 2.4V with 0.8V corresponding to zero sense
voltage (zero current).
FCB (Pin 39): Forced Continuous Input. Tie this pin to
ground to force continuous synchronous operation at low
load, to INTV
low load or to a resistive divider from a secondary output
when using a secondary winding.
I
to this pin to set the one-shot timer current and thereby
set the switching frequency.
V
connects the error amplifier input to an external resistive
divider from V
EXTV
ceeds 4.7V, an internal switch connects this pin to INTV
and shuts down the internal regulator so that controller and
gate drive power is drawn from EXTV
7V at this pin and ensure that EXTV
SV
INTV
driver and control circuits are powered from this voltage.
Decouple this pin to power ground with a minimum of
4.7μF low ESR tantalum or ceramic capacitor.
TH
ON
RNG
FB
IN
(Pin 38): Current Control Threshold and Error Amplifier
(Pin 41): On-Time Current Input. Tie a resistor from V
(Pin 43): Error Amplifier Feedback Input. This pin
(Pins 51, 52): Supply pin for internal PWM controller.
CC
CC
(Pin 37): Current Limit Range Input. The voltage
(Pins 53, 54): Internal 5V Regulator Output. The
(Pin 44): External V
CC
OUT
to enable discontinuous mode operation at
.
RNG
CC
pin is tied to ground which
Input. When EXTV
CC
CC
< V
. Do not exceed
IN
.
CC
3611fb
ex-
CC
CC
IN
.