input protection. It drives an external N-channel MOSFET
to replace a power Schottky diode. Its very low quiescent
current and fast transient response meet the tough require-
ments in automotive applications where AC input signals
of up to 100kHz are present. These signals are rectified
with minimum power dissipation on the external FET,
simplifying thermal management on the PCB.
With a drop of only 20mV, the LT8672 solution eases the
minimum input voltage requirement during cold crank
and start-stop, allowing simpler and more efficient cir-
cuits. If the input power source fails or is shorted, a fast
turn-off minimizes reverse current transients. An available
shutdown mode reduces the quiescent current to 3.5μA.
An integrated auxiliary boost regulator provides the re-
quired boost voltage to turn the external FET fully on. A
power good pin signals when the external FET is ready to
take load current.
All registered trademarks and trademarks are the property of their respective owners.
n
n
n
n
n
n
Reverse Input Protection to –40V
Improved Performance Compared to a
Schottky Diode:
n
Reduce Power Dissipation by >90%
n
Reduce Drop to 20mV
Ultrafast Transient Response
n
Rectifies 6V
P-P
Up to 50kHz
n
Rectifies 2V
P-P
Up to 100kHz
Wide Operating Voltage Range: 3V to 42V
Low 20µA Quiescent Current in Operation
Low 3.5µA Shutdown Current
Accurate 1.21V Enable Pin Threshold
Small 10-Lead MSOP Package or 10-Lead
3mm × 2mm DFN Package
APPLICATIONS
n
n
n
Automotive Battery Protection
Industrial Supplies
Portable Instrumentation
TYPICAL APPLICATION
12V, 5A Automotive Reverse Battery Protection
V
BATT
12V
SMBJ33A
33V
SMBJ15A
SOURCE GATE DRAIN AUX
15V
LT8672
ON OFF
EN/UVLO
GND
8672 TA01a
Rectification of Input Ripple
V
OUT
5A
470µF
V
OUT
2V/DIV
V
BATT
2V/DIV
IPD100N06S4-03
TO SYSTEM LOADS
1 F
100 H
4.7µF
+
AUXSW
PG
500µs/DIV
8672 TA01b
Rev B
Document Feedback
For more information
www.analog.com
1
LT8672
ABSOLUTE MAXIMUM RATINGS
(Notes 1 and 2)
DRAIN ...................................................... –0.3V to 42V
SOURCE, EN/UVLO ................................... –40V to 42V
DRAIN–SOURCE ......................................... –5V to 54V
AUX .......................................................... V
DRAIN
+ 13V
GATE .........................V
SOURCE
– 0.3V to V
SOURCE
+ 17V
GATE ................................... V
AUX
– 67V to V
AUX
+ 0.3V
PG .............................................................. –0.3V to 5V
Operating Junction Temperature Range (Notes 3, 4)
E-, I-Grades ..................................... −40°C to 125°C
H-Grades ......................................... −40°C to 150°C
Storage Temperature Range ................ −65°C to 150°C
Lead Temperature (Soldering, 10 sec)
MS Package .................................................... 300°C
PIN CONFIGURATION
TOP VIEW
TOP VIEW
EN/UVLO
GND
PG
GND
NC
1
2
3
4
5
10
9
8
7
6
GATE
SOURCE
DRAIN
AUX
AUXSW
EN/UVLO 1
GND 2
PG 3
GND 4
NC 5
11
10 GATE
9
8
7
6
SOURCE
DRAIN
AUX
AUXSW
MS PACKAGE
10-LEAD PLASTIC MSOP
θ
JA
= 160°C/W
DDB PACKAGE
10-LEAD (3mm
×
2mm) PLASTIC DFN
θ
JA
= 76°C/W,
θ
JA
= 13.5°C/W
EXPOSED PAD (PIN 11) MUST BE SHORTED TO GND OR LEFT FLOATING
ORDER INFORMATION
LEAD FREE FINISH
LT8672EMS#PBF
LT8672IMS#PBF
LT8672HMS#PBF
LT8672EDDB#PBF
LT8672IDDB#PBF
LT8672HDDB#PBF
TAPE AND REEL
LT8672EMS#TRPBF
LT8672IMS#TRPBF
LT8672HMS#TRPBF
LT8672EDDB#TRPBF
LT8672IDDB#TRPBF
LT8672HDDB#TRPBF
PART MARKING*
LTGYT
LTGYT
LTGYT
LGYS
LGYS
LGYS
PACKAGE DESCRIPTION
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead (3mm × 2mm) Plastic
10-Lead (3mm × 2mm) Plastic
10-Lead (3mm × 2mm) Plastic
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–40°C to 150°C
–40°C to 125°C
–40°C to 125°C
–40°C to 150°C
Consult ADI Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
Tape and reel specifications.
Some packages are available in 500 unit reels through designated sales channels with #TRMPBF suffix.
Rev B
2
For more information
www.analog.com
LT8672
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
SOURCE
= V
DRAIN
= 12V, unless otherwise noted. (Note 3)
PARAMETER
Minimum Drain Voltage
Total System Quiescent Current
V
EN/UVLO
= 0V
l
ELECTRICAL CHARACTERISTICS
CONDITIONS
l
MIN
TYP
2.85
3.5
20
20
MAX
3
5
15
26
39
1.34
1.26
0.1
0.1
UNITS
V
µA
µA
µA
µA
V
V
mV
µA
µA
Ω
V
mA
Ω
V
V
EN/UVLO
= 2V, Active Rectifier Controller
In Regulation (Note 4)
EN/UVLO Pin Threshold High
EN/UVLO Pin Threshold Low
EN/UVLO Pin Hysteresis
EN/UVLO Pin Current
PG Pin Leakage
PG Pull-Down Resistance
Auxiliary Boost Regulator
Regulation Voltage V
AUX
– V
DRAIN
Power NMOS Current Limit
Power NMOS On-Resistance
Catch Diode Forward Voltage
AUXSW Pin Leakage
Active Rectifier Controller
SOURCE–DRAIN Regulation Voltage
SOURCE–DRAIN Fast Pull-Up Threshold
DRAIN Current
SOURCE Current
Maximum Gate Drive (GATE–SOURCE)
Gate Pull-Up Current
Gate Pull-Down Current
Gate-Source Off Voltage for Reverse SOURCE
Gate Turn-Off Delay Time
Gate Turn-On Delay Time
Maximum Frequency of AC Input Signal to Be
Rectified
Fault Condition, V
SOURCE
= –5V, I
GATE
= 1mA
Fault Condition, V
SOURCE
= –40V, I
GATE
= 1mA
Step (V
SOURCE
–V
DRAIN
) from 130mV to −70mV
V
GATE
–V
SOURCE
< 1V, C
GATE–SOURCE
= 10nF
Step (V
SOURCE
–V
DRAIN
) from −70mV to 130mV
V
GATE
–V
SOURCE
> 5V , C
GATE–SOURCE
= 10nF
AC Input Ripple < 6V
P-P
, C
GATE–SOURCE
= 10nF
AC Input Ripple < 2V
P-P
, C
GATE–SOURCE
= 10nF
With Gate Driver in Regulation
With Gate Driver in Regulation
Fault Condition, V
SOURCE
= –40V
I
DIODE
= 100mA
V
AUXSW
= 12V
V
EN/UVLO
= 2V
V
PG
= 3.3V
V
PG
= 0.1V
Pin Voltage Rising
Pin Voltage Falling
l
l
l
1.22
1.16
–0.1
–0.1
1.28
1.21
70
l
650
10.2
75
11
100
2
0.8
–0.2
2000
11.8
120
l
l
0.2
20
75
12
5
–1
11.8
25
90
µA
mV
mV
µA
µA
mA
V
mA
mA
l
l
10
60
l
10.2
–26
170
11
–50
300
0.01
0.01
0.6
1.7
l
l
l
l
l
l
0.3
0.3
1.1
3.1
V
V
µs
µs
kHz
kHz
50
100
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect the device
reliability and lifetime.
Note 2:
Positive currents flow into pins, negative currents flow out of pins.
Minimum and Maximum values refer to absolute values.
Note 3:
The LT8672E is guaranteed to meet performance specifications
from 0°C to 125°C junction temperature. Specifications over the −40°C
to 125°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LT8672I is guaranteed over the full −40°C to 125°C operating junction
temperature range. The LT8672H is guaranteed over the full −40°C to
150°C operating junction temperature range.
Note 4:
Total system current with active rectifier controller in regulation.
