LM74700-Q1_V01 [TI]
LM74700-Q1 Low IQ Reverse Battery Protection Ideal Diode Controller;
| 型号： | LM74700-Q1_V01 |
| 厂家： | 
TEXAS INSTRUMENTS |
| 描述： | LM74700-Q1 Low IQ Reverse Battery Protection Ideal Diode Controller 电池 |
| 文件： | 总36页 (文件大小：3196K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
LM74700-Q1
SNOSD17G – OCTOBER 2017 – REVISED DECEMBER 2020
LM74700-Q1 Low IQ Reverse Battery Protection Ideal Diode Controller
1 Features
3 Description
•
AEC-Q100 qualified with the following results
– Device temperature grade 1:
–40°C to +125°C ambient operating
temperature range
– Device HBM ESD classification level 2
– Device CDM ESD classification level C4B
Functional Safety-Capable
– Documentation available to aid functional safety
system design
3.2-V to 65-V input range (3.9-V start up)
–65-V reverse voltage rating
The LM74700-Q1 is an automotive AEC Q100
qualified ideal diode controller which operates in
conjunction with an external N-channel MOSFET as
an ideal diode rectifier for low loss reverse polarity
protection with a 20-mV forward voltage drop. The
wide supply input range of 3.2 V to 65 V allows control
of many popular DC bus voltages such as 12-V, 24-V
and 48-V automotive battery systems. The 3.2-V input
voltage support is particularly well suited for severe
cold crank requirements in automotive systems. The
device can withstand and protect the loads from
negative supply voltages down to –65 V.
•
•
•
•
•
Charge pump for external N-Channel MOSFET
20-mV ANODE to CATHODE forward voltage drop
regulation
The device controls the GATE of the MOSFET to
regulate the forward voltage drop at 20 mV. The
regulation scheme enables graceful turn off of the
MOSFET during a reverse current event and ensures
zero DC reverse current flow. Fast response (< 0.75
µs) to Reverse Current Blocking makes the device
suitable for systems with output voltage holdup
requirements during ISO7637 pulse testing as well as
power fail and input micro-short conditions.
•
•
•
•
•
Enable pin feature
1-µA shutdown current (EN=Low)
80-µA operating quiescent current (EN=High)
2.3-A peak gate turnoff current
Fast response to reverse current blocking:
< 0.75 µs
•
•
Meets automotive ISO7637 transient requirements
with a suitable TVS Diode
Available in 6-pin and 8-pin SOT-23 Package 2.90
mm × 1.60 mm
The LM74700-Q1 controller provides a charge pump
gate drive for an external N-channel MOSFET. The
high voltage rating of LM74700-Q1 helps to simplify
the system designs for automotive ISO7637
protection. With the enable pin low, the controller is off
and draws approximately 1 µA of current.
2 Applications
•
•
Automotive ADAS systems - camera
Automotive infotainment systems - digital cluster,
head unit
Industrial factory automation - PLC
Enterprise power supplies
Device Information (1)
PART NUMBER
PACKAGE
SOT-23 (6)
SOT-23 (8)
BODY SIZE (NOM)
2.90 mm × 1.60 mm
2.90 mm × 1.60 mm
LM74700-Q1
•
•
•
LM74700-Q1
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Active ORing for redundant power
VOUT
VBATT
TVS
VOUT
VGATE
VBATT
Voltage
Regulator
GATE CATHODE
LM74700
ANODE
VCAP
EN
IBATT
GND
ON OFF
Typical Application Schematic
Reverse Current Blocking During Input Short
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. UNLESS OTHERWISE NOTED, this document contains PRODUCTION
DATA.
LM74700-Q1
SNOSD17G – OCTOBER 2017 – REVISED DECEMBER 2020
www.ti.com
Table of Contents
1 Features............................................................................1
2 Applications.....................................................................1
3 Description.......................................................................1
4 Revision History.............................................................. 2
5 Pin Configuration and Functions...................................3
6 Specifications.................................................................. 5
6.1 Absolute Maximum Ratings........................................ 5
6.2 ESD Ratings............................................................... 5
6.3 Recommended Operating Conditions.........................5
6.4 Thermal Information....................................................6
6.5 Electrical Characteristics.............................................6
6.6 Switching Characteristics............................................7
7 Typical Characteristics................................................... 8
8 Parameter Measurement Information.......................... 11
9 Detailed Description......................................................12
9.1 Overview...................................................................12
9.2 Functional Block Diagram.........................................12
9.3 Feature Description...................................................13
9.4 Device Functional Modes..........................................15
10 Application and Implementation................................16
10.1 Application Information........................................... 16
10.2 OR-ing Application Configuration............................22
11 Power Supply Recommendations..............................22
12 Layout...........................................................................23
12.1 Layout Guidelines................................................... 23
12.2 Layout Example...................................................... 24
13 Device and Documentation Support..........................25
13.1 Receiving Notification of Documentation Updates..25
13.2 Support Resources................................................. 25
13.3 Trademarks.............................................................25
13.4 Electrostatic Discharge Caution..............................25
13.5 Glossary..................................................................25
14 Mechanical, Packaging, and Orderable
Information.................................................................... 25
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision F (December 2019) to Revision G (December 2020)
Page
•
•
•
Updated the numbering format for tables, figures and cross-references throughout the document...................1
Added DDF (SOT-23) package option to data sheet..........................................................................................1
Relaxed VCAP specs in Electrical Characteristics table.................................................................................... 5
Changes from Revision E (February 2019) to Revision F (December 2019)
Page
•
Added the Functional safety capable link to the Features section......................................................................1
Changes from Revision D (January 2019) to Revision E (February 2019)
Page
•
Changed from Advance Information to Production Data ................................................................................... 1
Changes from Revision C (November 2018) to Revision D (January 2019)
Page
•
•
•
•
Added Typical Characteristics section ...............................................................................................................8
Added Parameter Measurement Information section .......................................................................................11
Deleted Application Limitations section ........................................................................................................... 22
Added Or-ing Application Configuration section ..............................................................................................22
Changes from Revision B (October 2018) to Revision C (November 2018)
Added footnotes to the Absolute Maximum Ratings and Recommended Operating Conditions tables in the
Specifications section......................................................................................................................................... 5
Page
•
Changes from Revision A (March 2018) to Revision B (October 2018)
Page
•
Changes made in the Specifications and Application Limitations sections........................................................ 1
Changes from Revision * (October 2017) to Revision A (March 2018)
Page
•
Multiple changes made throughout Data Sheet..................................................................................................1
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5 Pin Configuration and Functions
VCAP
GND
EN
ANODE
1
2
3
6
5
4
GATE
CATHODE
Figure 5-1. DBV Package 6-Pin SOT-23 Top View
Table 5-1. Pin Functions
PIN
I/O(1)
DESCRIPTION
NO.
1
NAME
VCAP
GND
O
G
I
Charge pump output. Connect to external charge pump capacitor
Ground pin
2
3
EN
Enable pin. Can be connected to ANODE for always ON operation
Cathode of the diode. Connect to the drain of the external N-channel MOSFET
Gate drive output. Connect to gate of the external N-channel MOSFET
4
CATHODE
GATE
I
5
O
Anode of the diode and input power. Connect to the source of the external N-channel
MOSFET
6
ANODE
I
(1) I = Input, O = Output, G = GND
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EN
CATHODE
N.C
1
2
3
4
8
7
GND
N.C
GATE
6
5
ANODE
VCAP
Figure 5-2. DDF Package 8-Pin SOT-23 Top View
Table 5-2. Pin Functions
PIN
I/O(1)
DESCRIPTION
NO.
1
NAME
EN
I
Enable pin. Can be connected to ANODE for always ON operation
2
GND
N.C
G
Ground pin
3
No connection
4
VCAP
O
I
Charge pump output. Connect to external charge pump capacitor
Anode of the diode and input power. Connect to the source of the external N-channel
MOSFET
5
ANODE
6
7
8
GATE
N.C
O
Gate drive output. Connect to gate of the external N-channel MOSFET
No connection
CATHODE
I
Cathode of the diode. Connect to the drain of the external N-channel MOSFET
(1) I = Input, O = Output, G = GND
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6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)(1)
MIN
–65
MAX
65
UNIT
ANODE to GND
V
V
V
V
V
Input Pins
EN to GND, V(ANODE) > 0 V
EN to GND, V(ANODE) ≤ 0 V
GATE to ANODE
–0.3
65
V(ANODE)
–0.3
(65 + V(ANODE))
15
15
Output Pins
VCAP to ANODE
–0.3
Output to Input
Pins
CATHODE to ANODE
–5
75
V
Operating junction temperature(2)
–40
–40
150
150
°C
°C
Storage temperature, Tstg
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under
Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device
reliability.
(2) High junction temperatures degrade operating lifetimes. Operating lifetime is de-rated for junction temperatures greater than 125°C.
6.2 ESD Ratings
VALUE
UNIT
Human body model (HBM), per AEC Q100-002(1)
±2000
Corner pins (VCAP, EN,
ANODE, CATHODE)
V(ESD)
Electrostatic discharge
±750
±500
V
Charged device model (CDM),
per AEC Q100-011
Other pins
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)(1)
MIN
NOM
MAX
60
UNIT
ANODE to GND
CATHODE to GND
EN to GND
–60
Input Pins
60
V
–60
–70
60
Input to Output
pins
ANODE to CATHODE
V
ANODE
22
nF
µF
External
capacitance
CATHODE, VCAP to ANODE
0.1
External
MOSFET max GATE to ANODE
VGS rating
15
V
TJ
Operating junction temperature range(2)
–40
150
°C
(1) Recommended Operating Conditions are conditions under which the device is intended to be functional. For specifications and test
conditions, see Electrical Characteristics.
(2) High junction temperatures degrade operating lifetimes. Operating lifetime is de-rated for junction temperatures greater than 125°C.
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6.4 Thermal Information
LM74700-Q1
DBV (SOT)
6 PINS
189.8
LM74700-Q1
DDF (SOT)
8 PINS
133.8
THERMAL METRIC(1)
UNIT
RθJA
Junction-to-ambient thermal resistance
Junction-to-case (top) thermal resistance
Junction-to-board thermal resistance
Junction-to-top characterization parameter
°C/W
°C/W
°C/W
°C/W
RθJC(top)
RθJB
103.8
72.6
45.8
54.5
ΨJT
19.4
4.6
Junction-to-board characterization
parameter
ΨJB
45.5
54.2
°C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report, SPRA953.
6.5 Electrical Characteristics
TJ = –40°C to +125°C; typical values at TJ = 25°C, V(ANODE) = 12 V, C(VCAP) = 0.1 µF, V(EN) = 3.3 V, over operating free-air
temperature range (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX UNIT
VANODE SUPPLY VOLTAGE
V(ANODE)
Operating input voltage
4
60
3.9
V
V
VANODE POR Rising threshold
VANODE POR Falling threshold
V(ANODE POR)
2.2
2.8
3.1
V
V(ANODE POR(Hys)) VANODE POR Hysteresis
0.44
0.67
1.5
V
I(SHDN)
Shutdown Supply Current
V(EN) = 0 V
0.9
80
µA
µA
I(Q)
Operating Quiescent Current
130
ENABLE INPUT
V(EN_IL)
Enable input low threshold
Enable input high threshold
Enable Hysteresis
0.5
1.06
0.52
0.9
2
1.22
2.6
1.35
5
V
V(EN_IH)
V(EN_Hys)
I(EN)
VANODE to VCATHODE
V(AK REG)
V
Enable sink current
V(EN) = 12 V
3
µA
Regulated Forward V(AK) Threshold
13
34
20
50
29
57
mV
mV
V(AK) threshold for full conduction
mode
V(AK)
V(AK) threshold for reverse current
blocking
V(AK REV)
–17
–11
–2
mV
Regulation Error AMP
Transconductance(1)
Gm
1200
1800
3100 µA/V
GATE DRIVE
V(ANODE) – V(CATHODE) = 100 mV,
V(GATE) – V(ANODE) = 5 V
Peak source current
3
11
2370
26
mA
mA
µA
V(ANODE) – V(CATHODE) = –20 mV,
V(GATE) – V(ANODE) = 5 V
I(GATE)
Peak sink current
V(ANODE) – V(CATHODE) = 0 V,
V(GATE) – V(ANODE) = 5 V
Regulation max sink current
discharge switch RDSON
6
V(ANODE) – V(CATHODE) = –20 mV,
V(GATE) – V(ANODE) = 100 mV
RDSON
0.4
2
Ω
CHARGE PUMP
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6.5 Electrical Characteristics (continued)
TJ = –40°C to +125°C; typical values at TJ = 25°C, V(ANODE) = 12 V, C(VCAP) = 0.1 µF, V(EN) = 3.3 V, over operating free-air
temperature range (unless otherwise noted)
PARAMETER
TEST CONDITIONS
V(VCAP) – V(ANODE) = 7 V
V(VCAP) – V(ANODE) = 14 V
I(VCAP) ≤ 30 µA
MIN
TYP
MAX UNIT
Charge Pump source current (Charge
pump on)
162
300
600
10
µA
µA
V
I(VCAP)
Charge Pump sink current (Charge
pump off)
5
Charge pump voltage at V(ANODE)
3.2 V
=
8
Charge pump turn on voltage
Charge pump turn off voltage
10.8
11.6
12.1
13
12.9
13.9
V
V
V(VCAP) – V(ANODE)
Charge Pump Enable comparator
Hysteresis
0.54
5.8
0.9
6.6
1.36
7.7
6
V
V
V
V(VCAP) – V(ANODE) UV release at rising
edge
V(ANODE) – V(CATHODE) = 100 mV
V(ANODE) – V(CATHODE) = 100 mV
V(VCAP UVLO)
V(VCAP) – V(ANODE) UV threshold at
falling edge
5.11
5.68
CATHODE
V(ANODE) = 12 V, V(ANODE)
V(CATHODE) = –100 mV
–
1.7
2
µA
I(CATHODE)
CATHODE sink current
V(ANODE) – V(CATHODE) = –100 mV
V(ANODE) = –12 V, V(CATHODE) = 12 V
1.2
2.2
µA
µA
1.25
2.06
(1) Parameter guaranteed by design and characterization
6.6 Switching Characteristics
TJ = –40°C to +125°C; typical values at TJ = 25°C, V(ANODE) = 12 V, C(VCAP) = 0.1 µF, V(EN) = 3.3 V, over operating free-air
temperature range (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX UNIT
Enable (low to high) to Gate Turn On
delay
ENTDLY
V(VCAP) > V(VCAP UVLOR)
75
110
0.75
2.6
µs
µs
µs
Reverse voltage detection to Gate Turn V(ANODE) – V(CATHODE) = 100 mV to –100
Off delay mV
tReverse delay
tForward recovery
0.45
1.4
Forward voltage detection to Gate Turn V(ANODE) – V(CATHODE) = –100 mV to 700
On delay
mV
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7 Typical Characteristics
6.5
6
700
650
600
550
500
450
400
350
300
250
200
150
100
50
-40èC
25èC
5.5
5
85èC
125èC
150èC
4.5
4
3.5
3
2.5
2
-40èC
25èC
1.5
1
85èC
125èC
150èC
0.5
0
0
0
5
10 15 20 25 30 35 40 45 50 55 60 65
VANODE (V)
0
5
10 15 20 25 30 35 40 45 50 55 60 65
VANODE (V)
D001
D005
Figure 7-1. Shutdown Supply Current vs Supply Voltage
Figure 7-2. Operating Quiescent Current vs Supply Voltage
18
16
14
12
10
8
1.8
1.6
1.4
1.2
1
0.8
6
0.6
-40èC
-40èC
25èC
25èC
4
2
0
0.4
0.2
0
85èC
125èC
150èC
85èC
125èC
150èC
0
10
20
30 40
VANODE = VEN (V)
50
60
70
0
10
20
30 40
VANODE (V)
50
60
70
D002
D007
Figure 7-3. Enable Sink Current vs Supply Voltage
Figure 7-4. CATHODE Sink Current vs Supply Voltage
350
500
-40èC
450
25èC
300
250
200
150
85èC
400
125èC
150èC
350
300
250
200
150
100
50
-40èC
25èC
100
50
0
85èC
125èC
150èC
3
4.5
6
7.5
VANODE (V)
9
10.5
12
0
2
4
6
VCAP (V)
8
10
12
D012
D013
Figure 7-5. Charge Pump Current vs Supply Voltage at VCAP =
6 V
Figure 7-6. Charge Pump V-I Characteristics at VANODE > = 12
V
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7 Typical Characteristics (continued)
1.2
1
225
-40èC
200
175
150
125
100
75
25èC
85èC
125èC
150èC
0.8
0.6
0.4
0.2
0
50
25
0
-50
0
50
100
150
200
0
1
2
3
4 5
VCAP (V)
6
7
8
9
Temperature (èC)
D014
D025
Figure 7-8. Enable Falling Threshold vs Temperature
Figure 7-7. Charge Pump V-I Characteristics at VANODE = 3.2 V
0.5
2.06
2.04
2.02
2
0.49
0.48
0.47
0.46
0.45
0.44
0.43
1.98
1.96
1.94
1.92
1.9
1.88
1.86
-50
0
50
100
150
200
-50
0
50
100
150
200
Temperature (èC)
D015
Temperature (èC)
D024
Figure 7-9. Reverse Current Blocking Delay vs Temperature
Figure 7-10. Forward Recovery Delay vs Temperature
90
80
70
60
50
40
30
20
13
12.8
12.6
12.4
12.2
12
11.8
ENTDLY ON
ENTDLY OFF
VCAP OFF
VCAP ON
10
0
11.6
-50
-50
0
50
100
150
200
0
50
100
150 200
Temperature (èC)
Temperature (èC)
D018
D019
Figure 7-11. Enable to Gate Delay vs Temperature
Figure 7-12. Charge Pump ON/OFF Threshold vs Temperature
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7 Typical Characteristics (continued)
7
6.5
6
3.5
3
5.5
5
2.5
2
4.5
4
3.5
3
1.5
1
2.5
2
1.5
1
0.5
0
VCAP UVLOR
VCAP UVLOF
VANODE PORR
VANODE PORF
0.5
0
-50 -25
0
25
50
75 100 125 150 175 200
-50
0
50
100
150
200
Temperature (èC)
Temperature (èC)
D020
D021
Figure 7-13. Charge Pump UVLO Threshold vs Temperature
Figure 7-14. VANODE POR Threshold vs Temperature
100
80
60
40
20
0
-20
-40
-60
-80
-100
IGATE
-20
0
20
VANODE-VCATHODE (mV)
40
60
D022
Figure 7-15. Gate Current vs Forward Voltage Drop
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8 Parameter Measurement Information
3.3 V
0V
VGATE
90%
0 V
tENTDLY
t
100 mV
VANODE > VCATHODE
0 mV
VCATHODE > VANODE
-100 mV
VGATE
10%
0 V
tTREVERSE DELAY
t
700 mV
VANODE > VCATHODE
0 mV
VCATHODE > VANODE
-100 mV
VGATE
90%
0 V
tTFWD_RECOVERY
t
Figure 8-1. Timing Waveforms
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9 Detailed Description
9.1 Overview
The LM74700-Q1 ideal diode controller has all the features necessary to implement an efficient and fast reverse
polarity protection circuit or be used in an ORing configuration while minimizing the number of external
components. This easy to use ideal diode controller is paired with an external N-channel MOSFET to replace
other reverse polarity schemes such as a P-channel MOSFET or a Schottky diode. An internal charge pump is
used to drive the external N-Channel MOSFET to a maximum gate drive voltage of approximately 15 V. The
voltage drop across the MOSFET is continuously monitored between the ANODE and CATHODE pins, and the
GATE to ANODE voltage is adjusted as needed to regulate the forward voltage drop at 20 mV. This closed loop
regulation scheme enables graceful turn off of the MOSFET during a reverse current event and ensures zero DC
reverse current flow. A fast reverse current condition is detected when the voltage across ANODE and
CATHODE pins reduces below –11 mV , resulting in the GATE pin being internally connected to the ANODE pin
turning off the external N-channel MOSFET, and using the body diode to block any of the reverse current. An
enable pin, EN is available to place the LM74700-Q1 in shutdown mode disabling the N-Channel MOSFET and
minimizing the quiescent current.
9.2 Functional Block Diagram
CATHODE
ANODE
GATE
VANODE
VCAP
COMPARATOR
+
œ
Bias Rails
VANODE
+
50 mV
œ
GM AMP
+
œ
ENGATE
VANODE
VCAP_UV
GATE DRIVER
ENABLE
LOGIC
+
20 mV
œ
VCAP_UV
S
R
Q
Q
COMPARATOR
+
œ
+
-11 mV
œ
VANODE
VANODE
VCAP
Charge Pump
Enable Logic
Charge
Pump
REVERSE
PROTECTION
LOGIC
ENABLE LOGIC
VCAP_UV
VCAP
VCAP
EN
GND
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9.3 Feature Description
9.3.1 Input Voltage
The ANODE pin is used to power the LM74700-Q1's internal circuitry, typically drawing 80 µA when enabled and
1 µA when disabled. If the ANODE pin voltage is greater than the POR Rising threshold, then LM74700-Q1
operates in either shutdown mode or conduction mode in accordance with the EN pin voltage. The voltage from
ANODE to GND is designed to vary from 65 V to –65 V, allowing the LM74700-Q1 to withstand negative voltage
transients.
9.3.2 Charge Pump
The charge pump supplies the voltage necessary to drive the external N-channel MOSFET. An external charge
pump capacitor is placed between VCAP and ANODE pins to provide energy to turn on the external MOSFET. In
order for the charge pump to supply current to the external capacitor the EN pin voltage must be above the
specified input high threshold, V(EN_IH). When enabled the charge pump sources a charging current of 300-µA
typical. If EN pins is pulled low, then the charge pump remains disabled. To ensure that the external MOSFET
can be driven above its specified threshold voltage, the VCAP to ANODE voltage must be above the
undervoltage lockout threshold, typically 6.6 V, before the internal gate driver is enabled. Use Equation 1 to
calculate the initial gate driver enable delay.
V
(VCAP _UVLOR)
T DRV _EN = 75ms + C(VCAP)
x
(
)
300mA
(1)
where
•
•
C(VCAP) is the charge pump capacitance connected across ANODE and VCAP pins
V(VCAP_UVLOR) = 6.6 V (typical)
. To remove any chatter on the gate drive approximately 900 mV of hysteresis is added to the VCAP
undervoltage lockout. The charge pump remains enabled until the VCAP to ANODE voltage reaches 13 V,
typically, at which point the charge pump is disabled decreasing the current draw on the ANODE pin. The charge
pump remains disabled until the VCAP to ANODE voltage is below to 12.1 V typically at which point the charge
pump is enabled. The voltage between VCAP and ANODE continue to charge and discharge between 12.1 V
and 13 V as shown in Figure 9-1. By enabling and disabling the charge pump, the operating quiescent current of
the LM74700-Q1 is reduced. When the charge pump is disabled it sinks 5-µA typical.
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TON
TDRV_EN
TOFF
VIN
VANODE
0V
VEN
13 V
12.1 V
VCAP-VANODE
6.6 V
V(VCAP UVLOR)
GATE DRIVER
ENABLE
Figure 9-1. Charge Pump Operation
9.3.3 Gate Driver
The gate driver is used to control the external N-Channel MOSFET by setting the GATE to ANODE voltage to
the corresponding mode of operation. There are three defined modes of operation that the gate driver operates
under forward regulation, full conduction mode and reverse current protection, according to the ANODE to
CATHODE voltage. Forward regulation mode, full conduction mode and reverse current protection mode are
described in more detail in the Regulated conduction Mode, Full Conduction Mode and Reverse Current
Production Mode sections. Figure 9-2 depicts how the modes of operation vary according to the ANODE to
CATHODE voltage of the LM74700-Q1. The threshold between forward regulation mode and conduction mode is
when the ANODE to CATHODE voltage is 50 mV. The threshold between forward regulation mode and reverse
current protection mode is when the ANODE to CATHODE voltage is –11 mV.
Reverse Current
Protection Mode
Full Conduction Mode
Regulated Conduction Mode
GATE connected
to ANODE
GATE connected
to VCAP
GATE to ANODE Voltage Regulated
-11 mV
0 mV
20 mV
50 mV
VANODE œ VCATHODE
Figure 9-2. Gate Driver Mode Transitions
Before the gate driver is enabled following three conditions must be achieved:
•
•
•
The EN pin voltage must be greater than the specified input high voltage.
The VCAP to ANODE voltage must be greater than the undervoltage lockout voltage.
The ANODE voltage must be greater than VANODE POR Rising threshold.
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If the above conditions are not achieved, then the GATE pin is internally connected to the ANODE pin, assuring
that the external MOSFET is disabled. Once these conditions are achieved the gate driver operates in the
correct mode depending on the ANODE to CATHODE voltage.
9.3.4 Enable
The LM74700-Q1 has an enable pin, EN. The enable pin allows for the gate driver to be either enabled or
disabled by an external signal. If the EN pin voltage is greater than the rising threshold, the gate driver and
charge pump operates as described in Gate Driver and Charge Pump sections. If the enable pin voltage is less
than the input low threshold, the charge pump and gate driver are disabled placing the LM74700-Q1 in shutdown
mode. The EN pin can withstand a voltage as large as 65 V and as low as –65 V. This allows for the EN pin to
be connected directly to the ANODE pin if enable functionality is not needed. In conditions where EN is left
floating, the internal sink current of 3 uA pulls EN pin low and disables the device.
9.4 Device Functional Modes
9.4.1 Shutdown Mode
The LM74700-Q1 enters shutdown mode when the EN pin voltage is below the specified input low threshold
V(EN_IL). Both the gate driver and the charge pump are disabled in shutdown mode. During shutdown mode the
LM74700-Q1 enters low IQ operation with the ANODE pin only sinking 1 µA. When the LM74700-Q1 is in
shutdown mode, forward current flow through the external MOSFET is not interrupted but is conducted through
the MOSFET's body diode.
9.4.2 Conduction Mode
Conduction mode occurs when the gate driver is enabled. There are three regions of operating during
conduction mode based on the ANODE to CATHODE voltage of the LM74700-Q1. Each of the three modes is
described in the Regulated Condution Mode, Full Conduction Mode and Reverse Current Protection Mode
sections.
9.4.2.1 Regulated Conduction Mode
For the LM74700-Q1 to operate in regulated conduction mode, the gate driver must be enabled as described in
the Gate Driver section and the current from source to drain of the external MOSFET must be within the range to
result in an ANODE to CATHODE voltage drop of –11 mV to 50 mV. During forward regulation mode the ANODE
to CATHODE voltage is regulated to 20 mV by adjusting the GATE to ANODE voltage. This closed loop
regulation scheme enables graceful turn off of the MOSFET at very light loads and ensures zero DC reverse
current flow.
9.4.2.2 Full Conduction Mode
For the LM74700-Q1 to operate in full conduction mode the gate driver must be enabled as described in the
Gate Driver section and the current from source to drain of the external MOSFET must be large enough to result
in an ANODE to CATHODE voltage drop of greater than 50-mV typical. If these conditions are achieved the
GATE pin is internally connected to the VCAP pin resulting in the GATE to ANODE voltage being approximately
the same as the VCAP to ANODE voltage. By connecting VCAP to GATE the external MOSFET's RDS(ON) is
minimized reducing the power loss of the external MOSFET when forward currents are large.
9.4.2.3 Reverse Current Protection Mode
For the LM74700-Q1 to operate in reverse current protection mode, the gate driver must be enabled as
described in the Gate Driver section and the current of the external MOSFET must be flowing from the drain to
the source. When the ANODE to CATHODE voltage is typically less than –11 mV, reverse current protection
mode is entered and the GATE pin is internally connected to the ANODE pin. The connection of the GATE to
ANODE pin disables the external MOSFET. The body diode of the MOSFET blocks any reverse current from
flowing from the drain to source.
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10 Application and Implementation
Note
Information in the following applications sections is not part of the TI component specification, and TI
does not warrant its accuracy or completeness. TI’s customers are responsible for determining
suitability of components for their purposes, as well as validating and testing their design
implementation to confirm system functionality.
10.1 Application Information
The LM74700-Q1 is used with N-Channel MOSFET controller in a typical reverse polarity protection application.
The schematic for the 12-V battery protection application is shown in Figure 10-1 where the LM74700-Q1 is
used in series with a battery to drive the MOSFET Q1. The TVS is not required for the LM74700-Q1 to operate,
but they are used to clamp the positive and negative voltage surges. The output capacitor COUT is recommended
to protect the immediate output voltage collapse as a result of line disturbance.
10.1.1 Typical Application
Q1
Voltage
Regulator
COUT
CIN
VBAT
GATE CATHODE
LM74700
EN
TVS
ANODE
VCAP
VCAP
GND
Figure 10-1. Typical Application Circuit
10.1.1.1 Design Requirements
A design example, with system design parameters listed in Table 10-1 is presented.
Table 10-1. Design Parameters
DESIGN PARAMETER
EXAMPLE VALUE
12-V Battery, 12-V Nominal with 3.2-V Cold Crank and 35-V Load
Dump
Input voltage range
Output voltage
Output current range
3.2 V during Cold Crank to 35-V Load Dump
3-A Nominal, 5-A Maximum
Output capacitance
1-µF Minimum, 47-µF Typical Hold Up Capacitance
ISO 7637-2 and ISO 16750-2
Automotive EMC Compliance
10.1.1.2 Detailed Design Procedure
10.1.1.2.1 Design Considerations
•
•
Input operating voltage range, including cold crank and load dump conditions
Nominal load current and maximum load current
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10.1.1.2.2 MOSFET Selection
The important MOSFET electrical parameters are the maximum continuous drain current ID, the maximum drain-
to-source voltage VDS(MAX), the maximum source current through body diode and the drain-to-source On
resistance RDSON
.
The maximum continuous drain current, ID, rating must exceed the maximum continuous load current. The
maximum drain-to-source voltage, VDS(MAX), must be high enough to withstand the highest differential voltage
seen in the application. This would include any anticipated fault conditions. It is recommended to use MOSFETs
with voltage rating up to 60-V maximum with the LM74700-Q1 because anode-cathode maximum voltage is 65
V. The maximum VGS LM74700-Q1 can drive is 13 V, so a MOSFET with 15-V minimum VGS should be selected.
If a MOSFET with < 15-V VGS rating is selected, a zener diode can be used to clamp VGS to safe level. During
startup, inrush current flows through the body diode to charge the bulk hold-up capacitors at the output. The
maximum source current through the body diode must be higher than the inrush current that can be seen in the
application.
To reduce the MOSFET conduction losses, lowest possible RDS(ON) is preferred, but selecting a MOSFET based
on low RDS(ON) may not be beneficial always. Higher RDS(ON) will provide increased voltage information to
LM74700-Q1's reverse comparator at a lower reverse current. Reverse current detection is better with increased
RDS(ON). It is recommended to operate the MOSFET in regulated conduction mode during nominal load
conditions and select RDS(ON) such that at nominal operating current, forward voltage drop VDS is close to 20-mV
regulation point and not more than 50 mV.
As a guideline, it is suggested to choose (20 mV / ILoad(Nominal)) ≤ RDS(ON) ≤ ( 50 mV / ILoad(Nominal)).
MOSFET manufacturers usually specify RDS(ON) at 4.5-V VGS and 10-V VGS. RDS(ON) increases drastically below
4.5-V VGS and RDS(ON) is highest when VGS is close to MOSFET Vth. For stable regulation at light load
conditions, it is recommended to operate the MOSFET close to 4.5-V VGS, that is, much higher than MOSFET
gate threshold voltage. It is recommended to choose MOSFET gate threshold voltage Vth of 2-V to 2.5-V
maximum. Choosing a lower Vth MOSFET also reduces the turn ON time.
Based on the design requirements, preferred MOSFET ratings are:
•
•
•
60-V VDS(MAX) and ±20-V VGS(MAX)
RDS(ON) at 3-A nominal current: (20 mV / 3A ) ≤ RDS(ON) ≤ ( 50 mV / 3A ) = 6.67 mΩ ≤ RDS(ON) ≤ 16.67 mΩ
MOSFET gate threshold voltage Vth: 2V maximum
DMT6007LFG MOSFET from Diodes Inc. is selected to meet this 12-V reverse battery protection design
requirements and it is rated at:
•
•
•
60-V VDS(MAX) and ±20-V VGS(MAX)
RDS(ON) 6.5-mΩ typical and 8.5-mΩ maximum rated at 4.5-V VGS
MOSFET Vth: 2-V maximum
Thermal resistance of the MOSFET should be considered against the expected maximum power dissipation in
the MOSFET to ensure that the junction temperature (TJ) is well controlled.
10.1.1.2.3 Charge Pump VCAP, input and output capacitance
Minimum required capacitance for charge pump VCAP and input/output capacitance are:
•
•
•
VCAP: Minimum 0.1 µF is required; recommended value of VCAP (µF) ≥ 10 x CISS(MOSFET)(µF)
CIN: minimum 22 nF of input capacitance
COUT: minimum 100 nF of output capacitance
10.1.1.3 Selection of TVS Diodes for 12-V Battery Protection Applications
TVS diodes are used in automotive systems for protection against transients. In the 12-V battery protection
application circuit shown in Figure 10-2, a bi-directional TVS diode is used to protect from positive and negative
transient voltages that occur during normal operation of the car and these transient voltage levels and pulses are
specified in ISO 7637-2 and ISO 16750-2 standards.
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There are two important specifications are breakdown voltage and clamping voltage of the TVS. Breakdown
voltage is the voltage at which the TVS diode goes into avalanche similar to a zener diode and is specified at a
low current value typical 1 mA and the breakdown voltage should be higher than worst case steady state
voltages seen in the system. The breakdown voltage of the TVS+ should be higher than 24-V jump start voltage
and 35-V suppressed load dump voltage and less than the maximum ratings of LM74700-Q1 (65 V). The
breakdown voltage of TVS- should be beyond than maximum reverse battery voltage –16 V, so that the TVS- is
not damaged due to long time exposure to reverse connected battery.
Clamping voltage is the voltage the TVS diode clamps in high current pulse situations and this voltage is much
higher than the breakdown voltage. TVS diodes are meant to clamp transient pulses and should not interfere
with steady state operation. In the case of an ISO 7637-2 pulse 1, the input voltage goes up to –150 V with a
generator impedance of 10 Ω. This translates to 15 A flowing through the TVS - and the voltage across the TVS
would be close to its clamping voltage.
Q1
Voltage
Regulator
COUT
47 µF
CIN
22 nF
VBAT
GATE CATHODE
LM74700
EN
TVS
SMBJ33CA
ANODE
VCAP
0.1 µF
VCAP
GND
Figure 10-2. Typical 12-V Battery Protection with Single Bi-Directional TVS
The next criterion is that the absolute maximum rating of Anode to Cathode reverse voltage of the LM74700-Q1
(–75 V) and the maximum VDS rating MOSFET are not exceeded. In the design example, 60-V rated MOSFET is
chosen and maximum limit on the cathode to anode voltage is 60 V.
In case of ISO 7637-2 pulse 1, the anode of LM74700-Q1 is pulled down by the ISO pulse and clamped by
TVS-. The MOSFET is turned off quickly to prevent reverse current from discharging the bulk output capacitors.
When the MOSFET turns off, the cathode to anode voltage seen is equal to (TVS Clamping voltage + Output
capacitor voltage). If the maximum voltage on output capacitor is 16 V (maximum battery voltage), then the
clamping voltage of the TVS- should not exceed, (60 V – 16) V = –44 V.
The SMBJ33CA TVS diode can be used for 12-V battery protection application. The breakdown voltage of 36.7
V meets the jump start, load dump requirements on the positive side and 16-V reverse battery connection on the
negative side. During ISO 7637-2 pulse 1 test, the SMBJ33CA clamps at –44 V with 15 A of peak surge current
as shown in Figure 10-5 and it meets the clamping voltage ≤ 44 V.
SMBJ series of TVS' are rated up to 600-W peak pulse power levels. This is sufficient for ISO 7637-2 pulses and
suppressed load dump (ISO-16750-2 pulse B).
10.1.1.4 Selection of TVS Diodes and MOSFET for 24-V Battery Protection Applications
Typical 24-V battery protection application circuit shown in Figure 10-3 uses two uni-directional TVS diodes to
protect from positive and negative transient voltages.
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Q1
TVS+
SMBJ58A
Voltage
Regulator
COUT
47 µF
CIN
22 nF
VBAT
GATE CATHODE
LM74700
EN
ANODE
VCAP
0.1 µF
VCAP
TVS-
SMBJ26A
GND
Figure 10-3. Typical 24-V Battery Protection with Two Uni-Directional TVS
The breakdown voltage of the TVS+ should be higher than 48-V jump start voltage, less than the absolute
maximum ratings of anode and enable pin of LM74700-Q1 (65 V) and should withstand 65-V suppressed load
dump. The breakdown voltage of TVS- should be lower than maximum reverse battery voltage –32 V, so that the
TVS- is not damaged due to long time exposure to reverse connected battery.
During ISO 7637-2 pulse 1, the input voltage goes up to –600 V with a generator impedance of 50 Ω. This
translates to 12 A flowing through the TVS-. The clamping voltage of the TVS- cannot be same as that of 12-V
battery protection circuit. Because during the ISO 7637-2 pulse, the Anode to Cathode voltage seen is equal to
(-TVS Clamping voltage + Output capacitor voltage). For a 24-V battery application, the maximum battery
voltage is 32 V, then the clamping voltage of the TVS- should not exceed, 75 V – 32 V = 43 V.
Single bi-directional TVS cannot be used for 24-V battery protection because breakdown voltage for TVS+ ≥ 65
V, maximum clamping voltage is ≤ 43 V and the clamping voltage cannot be less than the breakdown voltage.
Two un-directional TVS connected back-back needs to be used at the input. For positive side TVS+, SMBJ58A
with the breakdown voltage of 64.4 V (minimum), 67.8 (typical) is recommended. For the negative side TVS-,
SMBJ26A with breakdown voltage close to 32 V (to withstand maximum reverse battery voltage –32 V) and
maximum clamping voltage of 42.1 V is recommended.
For 24-V battery protection, a 75-V rated MOSFET is recommended to be used along with SMBJ26A and
SMBJ58A connected back-back at the input.
10.1.1.5 Application Curves
VOUT
VGATE
GATE TURNS OFF QUICKLY WITHIN1 ꢀs
VIN
TVS CLAMPING AT -42 V
IIN
Figure 10-4. ISO 7637-2 Pulse 1
Time (5 ms/DIV)
Figure 10-5. Response to ISO 7637-2 Pulse 1
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VIN
VIN
VGS FOLLOWS VCAP-ANODE AT 5.8A
VGS 4V: 3A LOAD CURRENT
VOUT
VOUT
VGATE
VGATE
IIN
IIN
Time (2 ms/DIV)
Time (2 ms/DIV)
Figure 10-7. Startup with 5.8-A Load
Figure 10-6. Startup with 3-A Load
GATE TURNS ON AT VCAP-ANODE:
6.6V
VGS FOLLOWS VCAP-ANODE AT 5.8A
VIN
VIN
VVCAP
VVCAP
VGATE
IIN
VGATE
IIN
Time (5 ms/DIV)
Time (5 ms/DIV)
Figure 10-9. VCAP During Startup at 5.8-A Load
Figure 10-8. VCAP During Startup at 3-A Load
VIN
VIN
ENABLE THRESHOLD: 2V
VEN
VEN
ENABLE TURN ON DELAY
VGATE
VGATE
IIN
IIN
Time (5 ms/DIV)
Time (100 µs/DIV)
Figure 10-10. Enable Threshold
Figure 10-11. Enable Turn ON Delay
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VIN1
VIN1
VOUT
VOUT
VOUT SWITCHES to VIN2 15V
VOUT SWITCHES to VIN2 15 V
VGATE1
VGATE1
IIN1
IIN2
VIN2 SUPPLIES LOAD CURRENT
Time (5 ms/DIV)
Time (5 ms/DIV)
Figure 10-13. ORing VIN1 to VIN2 Switch Over
Figure 10-12. ORing VIN1 to VIN2 Switch Over
VIN1
VIN1
VOUT SWITCHES to VIN1: 12V
VOUT
VOUT SWITCHES to VIN1: 12V
VOUT
VGATE1
VGATE1
IIN2
VIN1 SUPPLIES LOAD CURRENT
IIN1
Time (5 ms/DIV)
Time (5 ms/DIV)
Figure 10-15. ORing VIN2 to VIN1 Switch Over
Figure 10-14. ORing VIN2 to VIN1 Switch Over
VOUT
VIN1
VIN1
VOUT
VIN2
VGATE1
IIN1
IIN2
Time (10 ms/DIV)
Time (5 ms/DIV)
Figure 10-17. ORing - VIN2 Failure and Switch Over
to VIN1
Figure 10-16. ORing - VIN2 Failure and Switch Over
to VIN1
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10.2 OR-ing Application Configuration
Basic redundant power architecture comprises of two or more voltage or power supply sources driving a single
load. In its simplest form, the OR-ing solution for redundant power supplies consists of Schottky OR-ing diodes
that protect the system against an input power supply fault condition. A diode OR-ing device provides effective
and low cost solution with few components. However, the diodes forward voltage drops affects the efficiency of
the system permanently, since each diode in an OR-ing application spends most of its time in forward conduction
mode. These power losses increase the requirements for thermal management and allocated board space.
The LM74700-Q1 ICs combined with external N-Channel MOSFETs can be used in OR-ing Solution as shown in
Figure 10-18. The forward diode drop is reduced as the external N-Channel MOSFET is turned ON during
normal operation. LM74700-Q1 quickly detects the reverse current, pulls down the MOSFET gate fast, leaving
the body diode of the MOSFET to block the reverse current flow. An effective OR-ing solution needs to be
extremely fast to limit the reverse current amount and duration. The LM74700-Q1 devices in OR-ing
configuration constantly sense the voltage difference between Anode and Cathode pins, which are the voltage
levels at the power sources (VIN1, VIN2) and the common load point respectively. The source to drain voltage
VDS for each MOSFET is monitored by the Anode and Cathode pins of the LM74700-Q1. A fast comparator
shuts down the Gate Drive through a fast Pull-Down within 0.45 μs (typical) as soon as V(IN) – V(OUT) falls below
–11 mV. It turns on the Gate with 11-mA gate charge current once the differential forward voltage V(IN) – V(OUT)
exceeds 50 mV.
VIN1
GATE CATHODE
EN
ANODE
LM74700
VOUT
VCAP
GND
LOAD
COUT
VIN2
GATE CATHODE
EN
ANODE
LM74700
VCAP
GND
Figure 10-18. Typical OR-ing Application
Figure 10-12 to Figure 10-15 show the smooth switch over between two power supply rails VIN1 at 12 V and VIN2
at 15 V. Figure 10-16 and Figure 10-17 illustrate the performance when VIN2 fails. LM74700-Q1 controlling VIN2
power rail turns off quickly, so that the output remains uninterrupted and VIN1 is protected from VIN2 failure.
11 Power Supply Recommendations
The LM74700-Q1 Ideal Diode Controller designed for the supply voltage range of 3.2 V ≤ VANODE ≤ 65 V. If the
input supply is located more than a few inches from the device, an input ceramic bypass capacitor higher than
22 nF is recommended. To prevent LM74700-Q1 and surrounding components from damage under the
conditions of a direct output short circuit, it is necessary to use a power supply having over load and short circuit
protection.
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12 Layout
12.1 Layout Guidelines
•
•
•
•
•
•
Connect ANODE, GATE and CATHODE pins of LM74700-Q1 close to the MOSFET's SOURCE, GATE and
DRAIN pins.
The high current path of for this solution is through the MOSFET, therefore it is important to use thick traces
for source and drain of the MOSFET to minimize resistive losses.
The charge pump capacitor across VCAP and ANODE pins must be kept away from the MOSFET to lower
the thermal effects on the capacitance value.
The Gate pin of the LM74700-Q1 must be connected to the MOSFET gate with short trace. Avoid excessively
thin and long trace to the Gate Drive.
Keep the GATE pin close to the MOSFET to avoid increase in MOSFET turn-off delay due to trace
resistance.
Obtaining acceptable performance with alternate layout schemes is possible, however the layout shown in
the Layout Example is intended as a guideline and to produce good results.
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12.2 Layout Example
Signal VIA
Thermal VIA
Top Layer
Input TVS
CIN
VIN Plane
CVCAP
VCAP
ANODE
GATE
MOSFET SOURCE
GND
EN
GND Plane
CATHODE
Enable
Control
COUT
MOSFET DRAIN
VOUT Plane
Figure 12-1. LM74700-Q1 DBV Package Example Layout
MOSFET DRAIN
Signal Via
Power Via
Top layer
MOSFET SOURCE
VOUT PLANE
VIN PLANE
INPUT
TVS
COUT
CIN
CVCAP
GND PLANE
Figure 12-2. LM74700-Q1 DDF Package Example Layout
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13 Device and Documentation Support
13.1 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. Click on
Subscribe to updates to register and receive a weekly digest of any product information that has changed. For
change details, review the revision history included in any revised document.
13.2 Support Resources
TI E2E™ support forums are an engineer's go-to source for fast, verified answers and design help — straight
from the experts. Search existing answers or ask your own question to get the quick design help you need.
Linked content is provided "AS IS" by the respective contributors. They do not constitute TI specifications and do
not necessarily reflect TI's views; see TI's Terms of Use.
13.3 Trademarks
TI E2E™ is a trademark of Texas Instruments.
All trademarks are the property of their respective owners.
13.4 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled
with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric changes could cause the device not to meet its published
specifications.
13.5 Glossary
TI Glossary
This glossary lists and explains terms, acronyms, and definitions.
14 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
Copyright © 2020 Texas Instruments Incorporated
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25
Product Folder Links: LM74700-Q1
PACKAGE OPTION ADDENDUM
www.ti.com
1-Jan-2021
PACKAGING INFORMATION
Orderable Device
Status Package Type Package Pins Package
Eco Plan
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
Samples
Drawing
Qty
(1)
(2)
(3)
(4/5)
(6)
LM74700QDBVRQ1
LM74700QDBVTQ1
LM74700QDDFRQ1
ACTIVE
ACTIVE
SOT-23
SOT-23
DBV
DBV
DDF
6
6
8
3000 RoHS & Green
250 RoHS & Green
3000 RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
Level-2-260C-1 YEAR
Level-1-260C-UNLIM
-40 to 125
-40 to 125
-40 to 125
M747
M747
747F
NIPDAU
NIPDAU
ACTIVE SOT-23-THIN
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two
lines if the finish value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
1-Jan-2021
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
5-Jan-2021
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
B0
K0
P1
W
Pin1
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant
(mm) W1 (mm)
LM74700QDBVRQ1
LM74700QDBVTQ1
LM74700QDDFRQ1
SOT-23
SOT-23
DBV
DBV
DDF
6
6
8
3000
250
180.0
180.0
180.0
8.4
8.4
8.4
3.2
3.2
3.2
3.2
3.2
3.2
1.4
1.4
1.4
4.0
4.0
4.0
8.0
8.0
8.0
Q3
Q3
Q3
SOT-
3000
23-THIN
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
5-Jan-2021
*All dimensions are nominal
Device
Package Type Package Drawing Pins
SPQ
Length (mm) Width (mm) Height (mm)
LM74700QDBVRQ1
LM74700QDBVTQ1
LM74700QDDFRQ1
SOT-23
SOT-23
DBV
DBV
DDF
6
6
8
3000
250
213.0
213.0
210.0
191.0
191.0
185.0
35.0
35.0
35.0
SOT-23-THIN
3000
Pack Materials-Page 2
PACKAGE OUTLINE
DBV0006A
SOT-23 - 1.45 mm max height
S
C
A
L
E
4
.
0
0
0
SMALL OUTLINE TRANSISTOR
C
3.0
2.6
0.1 C
1.75
1.45
B
1.45 MAX
A
PIN 1
INDEX AREA
1
2
6
5
2X 0.95
1.9
3.05
2.75
4
3
0.50
6X
0.25
C A B
0.15
0.00
0.2
(1.1)
TYP
0.25
GAGE PLANE
0.22
0.08
TYP
8
TYP
0
0.6
0.3
TYP
SEATING PLANE
4214840/B 03/2018
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. Body dimensions do not include mold flash or protrusion. Mold flash and protrusion shall not exceed 0.15 per side.
4. Leads 1,2,3 may be wider than leads 4,5,6 for package orientation.
5. Refernce JEDEC MO-178.
www.ti.com
EXAMPLE BOARD LAYOUT
DBV0006A
SOT-23 - 1.45 mm max height
SMALL OUTLINE TRANSISTOR
PKG
6X (1.1)
1
6X (0.6)
6
SYMM
5
2
3
2X (0.95)
4
(R0.05) TYP
(2.6)
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE:15X
SOLDER MASK
OPENING
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
METAL
EXPOSED METAL
EXPOSED METAL
0.07 MIN
ARROUND
0.07 MAX
ARROUND
NON SOLDER MASK
DEFINED
SOLDER MASK
DEFINED
(PREFERRED)
SOLDER MASK DETAILS
4214840/B 03/2018
NOTES: (continued)
6. Publication IPC-7351 may have alternate designs.
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
www.ti.com
EXAMPLE STENCIL DESIGN
DBV0006A
SOT-23 - 1.45 mm max height
SMALL OUTLINE TRANSISTOR
PKG
6X (1.1)
1
6X (0.6)
6
SYMM
5
2
3
2X(0.95)
4
(R0.05) TYP
(2.6)
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
SCALE:15X
4214840/B 03/2018
NOTES: (continued)
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
9. Board assembly site may have different recommendations for stencil design.
www.ti.com
PACKAGE OUTLINE
DDF0008A
SOT-23 - 1.1 mm max height
S
C
A
L
E
4
.
0
0
0
PLASTIC SMALL OUTLINE
C
2.95
2.65
SEATING PLANE
TYP
PIN 1 ID
AREA
0.1 C
A
6X 0.65
8
1
2.95
2.85
NOTE 3
2X
1.95
4
5
0.4
0.2
8X
0.1
C A
B
1.65
1.55
B
1.1 MAX
0.20
0.08
TYP
SEE DETAIL A
0.25
GAGE PLANE
0.1
0.0
0 - 8
0.6
0.3
DETAIL A
TYPICAL
4222047/B 11/2015
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not
exceed 0.15 mm per side.
www.ti.com
EXAMPLE BOARD LAYOUT
DDF0008A
SOT-23 - 1.1 mm max height
PLASTIC SMALL OUTLINE
8X (1.05)
SYMM
1
8
8X (0.45)
SYMM
6X (0.65)
5
4
(R0.05)
TYP
(2.6)
LAND PATTERN EXAMPLE
SCALE:15X
SOLDER MASK
OPENING
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
METAL
SOLDER MASK
DEFINED
NON SOLDER MASK
DEFINED
SOLDER MASK DETAILS
4222047/B 11/2015
NOTES: (continued)
4. Publication IPC-7351 may have alternate designs.
5. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
www.ti.com
EXAMPLE STENCIL DESIGN
DDF0008A
SOT-23 - 1.1 mm max height
PLASTIC SMALL OUTLINE
8X (1.05)
SYMM
(R0.05) TYP
8
1
8X (0.45)
SYMM
6X (0.65)
5
4
(2.6)
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
SCALE:15X
4222047/B 11/2015
NOTES: (continued)
6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
7. Board assembly site may have different recommendations for stencil design.
www.ti.com
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