LTC3832 Datasheet, PDF (8/24 Pages) Linear Technology – High Power Step-Down Synchronous DC/DC Controllers for Low Voltage Operation

LTC3832/LTC3832-1
BLOCK DIAGRA (LTC3832-1)
INTERNAL
OSCILLATOR
THERMAL SHUTDOWN
DISABLE GATE DRIVE
POWER DOWN
COMP
SS
QC
–
PWM
+
12µA
QSS
ERR
+–
V_REF
2.2V
1.2V
V
SQ
RQ
FFG2
SQ
MAX POR R
ENABLE
G2
V_REF + 10%
PV_CC1
V_CC + 2.5V
V_REF
V_REF + 10%
PV_CC1
G1
V_CC/PV_CC2
G2
PGND
FB
BG
3832 BD2
TEST CIRCUITS
V_SHDN V_CC
PV_CC
SHDN V_CC PV_CC2 PV_CC1 I_FB
NC
FB
G1
NC
SS
NC
FREQSET
LTC3832
NC
COMP
I_MAX
G2
GND PGND SENSE^– SENSE⁺
6800pF
6800pF
Figure 2
3832 F02
V_COMP
V_FB
5V
I_FB
COMP
+
V_CC PV_CC1 PV_CC2
G1
LTC3832
10µF
0.1µF
G1 RISE/FALL
6800pF
FB
I_MAX
G2
GND PGND
G2 RISE/FALL
6800pF
3832 F03
Figure 3
APPLICATIO S I FOR ATIO
OVERVIEW
The LTC3832/LTC3832-1 are voltage mode feedback,
synchronous switching regulator controllers (see Block
Diagram) designed for use in high power, low voltage
step-down (buck) converters. They include an onboard
PWM generator, a precision reference trimmed to ±0.8%,
two high power MOSFET gate drivers and all necessary
8
feedback and control circuitry to form a complete switch-
ing regulator circuit. The PWM loop nominally runs at
300kHz.
The LTC3832 includes a current limit sensing circuit that
uses the topside external N-channel power MOSFET as a
current sensing element, eliminating the need for an
external sense resistor.
sn3832 3832fs