LTC4446 Datasheet, PDF (1/12 Pages) Linear Technology – High Voltage High Side/Low Side N-Channel MOSFET Driver

FEATURES
n _{Bootstrap Supply Voltage Up to 114V}
n _{Wide VCC Voltage: 7.2V to 13.5V}
n _{2.5A Peak Top Gate Pull-Up Current}
n _{3A Peak Bottom Gate Pull-Up Current}
n _{1.2Ω Top Gate Driver Pull-Down}
n _{0.55Ω Bottom Gate Driver Pull-Down}
n _{5ns Top Gate Fall Time Driving 1nF Load}
n _{8ns Top Gate Rise Time Driving 1nF Load}
n _{3ns Bottom Gate Fall Time Driving 1nF Load}
n _{6ns Bottom Gate Rise Time Driving 1nF Load}
n _{Drives Both High and Low Side N-Channel MOSFETs}
n _{Undervoltage Lockout}
n _{Thermally Enhanced 8-Pin MSOP Package}
APPLICATIONS
n _{Distributed Power Architectures}
n _{Automotive Power Supplies}
n _{High Density Power Modules}
n _{Telecommunication Systems}
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Protected by U.S. Patents including 6677210.
LTC4446
High Voltage High Side/
Low Side N-Channel
MOSFET Driver
DESCRIPTION
The LTC^®4446 is a high frequency high voltage gate driver
that drives two N-channel MOSFETs in a DC/DC converter
with supply voltages up to 100V. The powerful driver ca-
pability reduces switching losses in MOSFETs with high
gate capacitance. The LTC4446’s pull-up for the top gate
driver has a peak output current of 2.5A and its pull-down
has an output impedance of 1.2Ω. The pull-up for the bot-
tom gate driver has a peak output current of 3A and the
pull-down has an output impedance of 0.55Ω.
The LTC4446 is configured for two supply-independent
inputs. The high side input logic signal is internally
level-shifted to the bootstrapped supply, which may
function at up to 114V above ground.
The LTC4446 contains undervoltage lockout circuits that
disable the external MOSFETs when activated.
The LTC4446 is available in the thermally enhanced 8-lead
MSOP package.
The LTC4446 does not have adaptive shoot-through pro-
tection. For similar drivers with adaptive shoot-through
protection, please refer to the chart below.
PARAMETER
Shoot-Through Protection
Absolute Max TS
MOSFET Gate Drive
V_CC UV⁺
V_CC UV^–
LTC4446
No
100V
7.2V to 13.5V
6.6V
6.15V
LTC4444
Yes
100V
7.2V to 13.5V
6.6V
6.15V
LTC4444-5
Yes
100V
4.5V to 13.5V
4V
3.55V
TYPICAL APPLICATION
Two Switch Forward Converter
V_CC
7.2V TO 13.5V
PWM1
(FROM CONTROLLER IC)
PWM2
(FROM CONTROLLER IC)
BOOST
V_CC
TG
LTC4446
TINP
TS
BINP
BG
GND
V_IN
36V TO 72V
(100V ABS MAX)
• • _TO
SECONDARY
CIRCUIT
4446 TA01a
LTC4446 Driving a 1000pF Capacitive Load
BINP
5V/DIV
BG
10V/DIV
TINP
5V/DIV
TG-TS
10V/DIV
20ns/DIV
4446 TA01b
4446f
1