Texas Instruments LM74704Q1EVM User manual

EVM User's Guide: LM74704Q1EVM LM74704-Q1 LM74703-Q1
Evaluation Module for LM74704-Q1 and LM74703-Q1 Ideal
Diode Controllers
Description
The LM74704Q1EVM assists designers to evaluate
the operation and performance of the LM74704-Q1
and LM74703-Q1 ideal diode controllers (8-pin DDF
package). This evaluation module demonstrates how
an N-channel power MOSFET driven by LM74704-Q1
can emulate a very-low forward voltage diode with low
IQ and low-leakage current flowing through the IC.
Features
• Reverse current blocking feature required for
ORing application
• Input reverse battery protection
• FET_GOOD output to indicate external MOSFET
health status
• On-board voltage regulator to provide pull-up
voltage for open-drain FET_GOOD variant,
LM74704-Q1
• Meets 12-V battery automotive ISO7637 and
ISO16750-2 transient requirements
Applications
•Automotive ADAS systems - camera
•Automotive infotainment systems - digital cluster,
head unit
•Body electronics and lighting
LM74704Q1EVM
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1 Evaluation Module Overview
This user’s guide describes the LM74704Q1EVM evaluation modules (EVM). The default mounted device
is LM74704-Q1, and the EVM is also for LM74703-Q1 device as well. This guide provides configuration
information, test setup details and contains the EVM schematics, bill of materials, assembly drawings, and
top and bottom board layouts.
1.1 Introduction
In this design scheme, the LM74704-Q1 is combined with a MOSFET and used in series with a battery as a
replacement for a Schottky diode and PFET, in reverse-polarity protection circuitry as shown in Figure 2-1. For
more information on the LM74704-Q1 functional and electrical characteristics, see LM74703-Q1, LM74704-Q1
Ideal Diode Controller with External FET Health Indication.
1.2 Kit Contents
LM74704Q1EVM Kit Contents
Item Description Quantity
LM74704Q1EVM PCB 1
1.3 Specification
The LM74704Q1EVM has the following features:
• 3.9-V to 60-V input range
– While testing for input voltage greater than 35 V, remove input 33 V TVS or use an appropriate TVS
• 5 A max current
• Meets 12-V battery automotive ISO7637 and ISO16750-2 transient requirements
• LM74704-Q1 device populated by default and can be replaced with LM74703-Q1 IC for evaluation
1.4 Device Information
The LM74703-Q1, LM74704-Q1 is an auto-midotive AEC Q100 qualified diode controller which operates in
conjunction with an external N-channel MOSFET as an excellent 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 an excellent choice for severe cold crank requirements in automotive systems. The
device can withstand and protect the loads from negative supply voltages down to –65 V.
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2 Hardware
2.1 Setup
This section describes the jumpers and connectors on the EVM, and how to properly connect, setup, and use
the LM74704Q1EVM. Verify the power supply is turned off while making connections on the board.
2.1.1 I/O Connectors, Jumper and Test Points Description
I/O Connector Description
J1 VIN: Power input connector to the positive rail of the input power supply
J3 GND: Ground connection for the power supply
J2 VOUT: Power output connector to the positive side of the load
J4 GND: Ground connection for the load
Test Point Description
TP1 VIN: Test point for positive of input power supply
TP2 VOUT: Test point for positive side of the load
TP3 FET_GOOD: Test point for FET_GOOD pin
TP4 EN: Test point for EN pin
TP5, TP6 GND: Test point for GND
Jumper Description
J5 Populate for on board pull-up while testing LM74704-Q1 which has open-drain
FET_GOOD (Default Setting)
Do not populate while testing LM74703-Q1 as the device has push-pull
FET_GOOD output
V_EXT
VBATT
LM74704-Q1
GATE CATHODE
EN
ANODE
VCAP+
GND
D1
Q1
C1 C2
VBAT_PROT
FETGOOD
VCAP-
Figure 2-1. LM74704Q1EVM Typical Application Circuit
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2.1.2 Board Setup
Before applying power to the LM74704Q1EVM, verify all external connections. Turn off external power supplies
and connect them with the proper polarity to the VIN and GND connectors. An electronic or resistive load must
be connected at the output VOUT and GND connectors. The tests outlined in this document are conducted with
3-A constant current as the load and 12 V at the input. Make sure that the external power-supply source for
the input voltage is capable of providing enough current to the output load so that the output voltage can be
obtained.
When all connections to the LM74704Q1EVM are verified, apply power to VIN.
Figure 1-1 captures EVM board image.
2.2 Operation
2.2.1 Startup
Use the following instructions to capture the start-up profile of LM74704-Q1:
1. Set the input supply voltage VIN to 12 V and current limit of 5 A.
2. The default EVM configuration has EN tied to ANODE via R2. So, the device is enabled when input voltage
goes above V(EN_IH) threshold. This configuration allows us to capture startup with input voltage behavior of
the IC.
a. For startup with EN test, de-populate R2 and connect external control signal voltage to TP4 (EN).
3. Verify the jumper J5 is populated which connects the on board generated pull-up voltage to FET_GOOD
signal.
4. Turn ON the power supply.
5. Observe the start-up profile of VIN, VOUT, GATE and input current.
Figure 2-2 shows the startup wavefom of LM74704-Q1 while input voltage is ramped up from 0 V to 12 V.
VIN
VOUT
VGATE
IIN
VGS 4V: 3A LOAD CURRENT
Figure 2-2. Startup with VIN Ramp Up - LM74704-Q1
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Use the following instructions to capture the start-up profile of LM74703-Q1:
1. Replace U1 (default LM74704-Q1) on board with LM74703-Q1.
2. Set the input supply voltage, VIN to 12 V and current limit of 5 A.
3. The default EVM configuration has EN tied to ANODE via R2. So, the device is enabled when input voltage
V(EN_IH) threshold.
4. Verify the jumper J5 is de-populated as the LM74703-Q1 has push-pull output of FET_GOOD and does not
require an external pull-up voltage.
5. Turn ON the power supply.
6. Observe the start-up profile of VIN, VOUT, GATE and FET_GOOD.
Figure 2-3 shows the startup wavefom of LM74703-Q1 while input voltage is ramped up from 0 V to 12 V.
Figure 2-3. Startup with VIN Ramp Up - LM74703-Q1
2.2.2 FET Status Detection Test
To capture the device FET_GOOD pin behavior while starting up with the external FET short:
1. Connect a wire between TP1 and TP2 to emaulate the FET short behavior.
2. Set the input supply voltage VIN to 12 V and current limit of 5 A.
3. While testing with LM74704-Q1, verify the jumper J5 is populated which connects the on board generated
pull-up voltage to FET_GOOD signal.
a. For testing with external pull-up voltage, de-populate J5 jumper and apply external pull-up voltage to
TP3 (FET_GOOD).
4. While testing with LM74703-Q1, verify the jumper J5 is de-populated as the LM74703-Q1 has push-pull
output of FET_GOOD and does not require an external pull-up voltage.
5. Turn ON the power supply.
6. Observe the start-up profile of VIN, VOUT, GATE and FET_GOOD.
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Figure 2-4 shows startup with FET short behavior of LM74704-Q1.
Figure 2-4. FET_GOOD During Startup with FET Short (LM74704-Q1) with External Pull-Up Voltage
Figure 2-5 shows startup with FET short behavior of LM74703-Q1.
Figure 2-5. FETGOOD During Startup with FET Short (LM74703-Q1)
3 Hardware Design Files
Users can request the design files at https://www.ti.com.
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3.1 Schematic
Figure 3-1 illustrates the EVM schematic.
GND
D2
58V
C2
0
2.2µF
R2
J1
575-8
J3
575-8
J4
575-8
J2
575-8
220µF
C3
D4
24V
D3
58V
Vin= 3.9V to 60V
5A max Current
Vout = 3.9V to 60V
5A max Current
5VCAP- 8
CATHODE
EN
1
6ANODE
4VCAP+ 3
FETGOOD
7
GATE
2
LM74704DDF
GND
U1
1
23 Q3
GND
C5
2.2µF
25V
CATHODE
R3
10.0k
VREG
4.7V
D5
MM3Z4V7ST1G
1
2
J5
10.0k
R1
VREG
CAT HODE
C4
100nF
100nF
C1
D1
33V
0
R5
0
R4
5
4
1
3
2
Q1
5
4
1
3
2
Q2
VIN
TP1
VOUT
TP2
GND
GND
TP6
TP5
3TP
FET_GOOD
TP4
EN
TP7
GATE
Figure 3-1. LM74704Q1EVM Schematic
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3.2 PCB Drawings
Figure 3-2 through Figure 3-5 show component placement and layout of this EVM.
Figure 3-2. LM74704Q1EVM Top Side Placement
Figure 3-3. LM74704Q1EVM Bottom Side Placement
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Figure 3-4. LM74704Q1EVM Top Layer Routing
Figure 3-5. LM74704Q1EVM Bottom Layer Routing
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3.3 Bill of Materials
Table 3-1 lists the LM74704Q1EVM BOM.
Table 3-1. Bill of Materials
Designator Qty Value Description Package
Reference Part Number Manufacturer Alternate PartNumber
!PCB 1 Printed Circuit Board LP108 Any
C1 1 0.1uF
CAP, CERM, 0.1 µF, 100 V,+/-
10%, X7R, AEC-Q200 Grade
1, 0603
0603 HMK107B7104KAHT Taiyo Yuden
C2 1 2.2uF CAP, CERM, 2.2 µF, 100 V, +/-
10%, X7R, 1210 1210 C1210C225K1RACT UKemet
C3 1 220uF
CAP, AL, 220 µF, 63 V, +/-
20%, 0.16 ohm, AEC-Q200
Grade 2, SMD
SMT Radial H13 EEV-FK1J221Q Panasonic
C4 1 0.1uF
CAP, CERM, 0.1 uF, 25 V, +/-
10%, X7R, AEC-Q200 Grade
1, 0603
0603 CGA3E2X7R1E104K
080AA TDK
C5 1 2.2uF
CAP, CERM, 2.2 µF, 25 V,+/-
10%, X7R, AEC-Q200 Grade
1, 0805
0805 GCM21BR71E225KA
73L MuRata
D1 1 33 V Diode, TVS, Bi, 33 V, SMB SMB SMBJ33CA-13-F Diodes Inc.
D5 1 4.7V Diode, Zener, 4.7 V, 300 mW,
SOD-323 SOD-323 MM3Z4V7ST1G ON Semiconductor
H1, H2, H3, H4 4 Machine Screw, Round, #4-40
x 1/4, Nylon, Philips panhead Screw NY PMS 440 0025 PH
B&F Fastener
Supply
H5, H6, H7, H8 4 Standoff, Hex, 0.5"L #4-40
Nylon Standoff 1902C Keystone
J1, J2, J3, J4 4 Standard Banana Jack,
Uninsulated, 8.9mm Keystone575-8 575-8 Keystone
J5 1 Header, 100mil, 2x1, Tin, TH Header, 2 PIN,
100mil, Tin PEC02SAAN
Sullins
Connector
Solutions
Q1 1 60 V MOSFET, N-CH, 60 V, 100 A,
SOT669 SOT669 PSMN5R6-60YL Nexperia
Q3 1 160 V Transistor, NPN, 160 V, 0.3 A,
SOT-23 SOT-23 PMBT5551,215 Nexperia
R1 1 10.0k RES, 10.0 k, 1%, 0.1 W, AEC-
Q200 Grade 0, 0603 0603 RMCF0603FT10K0 Stackpole Electronics Inc
R2, R4, R5 3 0 RES, 0, 5%, 0.1 W, 0603 0603 CRCW06030000Z0E
AVishay-Dale
R3 1 10.0k RES, 10.0 k, 1%, 0.125 W,
AEC-Q200 Grade 0, 0805 0805 ERJ-6ENF1002V Panasonic
SH1 1 1x2 Shunt, 100mil, Gold plated,
Black Shunt SNT-100-BK-G Samtec 969102-0000-DA
TP1, TP2,
TP5, TP6 4TEST POINT SLOTTED .118", TH
Test point, TH
Slot Test point 1040 Keystone
TP3, TP4, TP7 3 Test Point, Miniature, Orange,
TH
Orange
Miniature
Testpoint
5003 Keystone
U1 1 Ideal Diode Controller with
FET Good Output, SOT23-8 SOT23-8 LM74704DDF Texas Instruments
D2 0 58 V Diode, TVS, Uni, 58 V, SMA SMA SMAJ58A Diodes Inc.
D3 0 58 V Diode, TVS, Uni, 58 V, 93.6
Vc, SMB SMB SMBJ58A-13-F Diodes Inc.
D4 0 24 V Diode, TVS, Uni, 24 V, 38.9
Vc, SMB SMB SMBJ24A-13-F Diodes Inc.
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