DDB115R1 EVB Input Filter Automotive Demo Board
“
Specifications:
- Product Name: DDB115R1 EVB
- Components: AP68255Q, AP68355Q, AP6A255Q, AP6A355Q DC-DC buck
converters, AP74700AQ ideal diode controller - Features: Reverse voltage protection, ISO 7637-2 transient
pulse protection, EMI filtering compliant with CISPR 25 Class
5
Product Usage Instructions:
Board Layout:
Refer to the provided figures for the top view, PCB top layer,
mid layers, and bottom layer of the board.
Quick Start Guide:
To evaluate the performance of the DDB115R1 demo board, follow
the procedure below:
- Set up your test as shown in Figure 6.
Measurement/Performance Guidelines:
Refer to the schematic circuit in Figure 7 for understanding the
connections and components used on the board.
Bill of Materials:
Check the provided bill of materials for the quantities,
references, values, descriptions, and packages of the components
used on the board.
FAQ:
Q: What are the key features of the DDB115R1 EVB?
A: The key features include reverse voltage
protection, ISO 7637-2 transient pulse protection, and EMI
filtering compliant with CISPR 25 Class 5.
Q: How can I start evaluating the DDB115R1 demo board?
A: Follow the quick start guide provided in the
user manual and set up your test according to the instructions and
test setup diagram.
Q: Where can I find the detailed layout of the DDB115R1
EVB?
A: The user manual includes figures depicting
the top view, PCB top layer, mid layers, and bottom layer of the
board for reference.
“`
DDB115R1 EVB User Guide
Input Filter + AP74700AQ + AP68xxxQ/AP6AxxxQ System Solution
General Description
The DDB115R1 Demo Board showcases the AP68255Q, AP68355Q, AP6A255Q, AP6A355Q DC-DC buck converter family, the AP74700AQ ideal diode controller, and the usage of an EMI input filter.
It demonstrates a system-level solution with reverse voltage protection, ISO 7637-2 transient pulse protection (using suitable TVS), EMI filtering that passes CISPR 25 Class 5, as well as the DC-DC buck converter.
The input filter contains a common-mode choke with capacitors on either side of it in a Pi configuration. This is connected in series with an LC low pass filter containing an inductor and capacitor. This combination makes the board CISPR 25 class 5 compliant.
Key Features
· All components qualified for automotive applications · CISPR 25 Class 5 Compliance · VIN 5.5V to 65V · VOUT Adjustable from 1.2V to 50V · Overcurrent Protection (OCP) · Fast reverse current block response time of < 0.75s · -65V Reverse Battery Voltage · Green electronics · Compliance with Automotive Transient Requirements
with Appropriate TVS ISO 7637-2 ISO 16750-2
Applications
· General-purpose point-of-load DC-DC power conversion
· Distributed power systems · 48V automotive applications
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Evaluation Board
DDB115R1 EVB User Guide
Input Filter + AP74700AQ + AP68xxxQ/AP6AxxxQ System Solution
Board Layout
Figure 1: EVM Top View
Figure 2: PCB Top Layer (Top View)
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DDB115R1 EVB User Guide
Input Filter + AP74700AQ + AP68xxxQ/AP6AxxxQ System Solution
Figure 3: PCB Mid Layer 1 (Top View)
Figure 4: PCB Mid Layer 2 (Top View)
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DDB115R1 EVB User Guide
Input Filter + AP74700AQ + AP68xxxQ/AP6AxxxQ System Solution
Figure 5: PCB Bottom Layer (Top View)
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DDB115R1 EVB User Guide
Input Filter + AP74700AQ + AP68xxxQ/AP6AxxxQ System Solution
Quick Start Guide
To evaluate the performance of the DDB115R1 demo board, follow the procedure below.
1. Connect a power supply to the input terminals VIN and GNDIN. Set VIN to 48V 2. Connect the positive terminal of the electronic load to VOUT and negative terminals to GND. 3. To Enable the board, J1 needs to be enabled. Place the header in the highlighted enabled position. 4. The demo board should power up with a 5V output voltage. 5. Check for correct output voltage of 5V (±1%) at the output terminals VOUT and 0V using a multimeter or similar. 6. Set the electronic load to 0.5A and increase to 2.5/3.5A. Check for stable output voltage and SW signal using an oscilloscope.
Figure 6: Test Setup
Measurement/Performance Guidelines
· When measuring the output voltage ripple, maintain the shortest possible ground lengths on the oscilloscope probe. Long ground leads can erroneously inject high frequency noise into the measured ripple.
· For efficiency measurements, connect an ammeter in series with the input supply to measure the input current. Connect an electronic load to the output for output current.
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Evaluation Board Schematic
DDB115R1 EVB User Guide
Input Filter + AP74700AQ + AP68xxxQ/AP6AxxxQ System Solution
Figure 7: Schematic Circuit
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DDB115R1 EVB User Guide
Input Filter + AP74700AQ + AP68xxxQ/AP6AxxxQ System Solution
Bill of Materials
Qty.
Ref.
1
U2
1
U1
1
Q1
1
D1
1
D2
1
C7
Value
Description
Package
–
AP68255Q/AP68355Q/AP6A255Q/ AP6A355Q
SO8-EP
–
AP74700AQ
SOT26
–
DMTH8028LFGQ/DMTH10H032LF VWQ N-Channel MOSFET
PowerDI333-8
–
SMF4LxxxAQ TVS
DO219-AA
–
SBR8M100P5Q / PDS5100Q Rectifier
PowerDI5
100nF Ceramic Capacitor 100V X7R 10%
0805
Manufacturer
Diodes Incorporated
Diodes Incorporated
Diodes Incorporated
Diodes Incorporated
Diodes Incorporated
Murata
Manufacturer P/N Provided by Customer Provided by Customer Provided by Customer Provided by Customer Provided by Customer GCM21BR72A104KA37L
2
C18, C19
100nF Ceramic Capacitor 50V X7R 10%
0402
Murata
GCM155R71H104KE02D
1
C16
1F Ceramic Capacitor 50V X7R 10%
0603
Yageo
CC0603KRX7R9BB105
1
C23
1
C22
2 C10, C11
10nF Ceramic Capacitor 100V X7R 10%
47pF
Ceramic Capacitor 100V C0G/NP0 5%
4.7F Ceramic Capacitor 100V X7S 10%
0402 0603 1210
Yageo Vishay Murata
CC0402KRX7R0BB103 VJ0603A470JXBAC
GCM32DC72A475KE02L
2 C15, C17
22F Ceramic Capacitor 25V X7R 10%
1210
Murata
GCM32EC71E226KE36L
1
C5
1F Ceramic Capacitor 100V X7S 10%
0805
7
C1, C2, C3, C4, C6, C8, C12
1
L1
100nF –
Ceramic Capacitor 100V X7R 10% Common-mode Choke
0603
7mm x 6mm x 3.5mm
1
L2
6.8H
Shielded Inductor
5050
Murata Murata Bourns Coilcraft
GRJ21BC72A105KE11L GRM188R72A104KA35D
SRF7035A-102Y XGL5050-682MEC
1
L3
68H
Shielded Inductor
12mm x 12mm
Coilcraft
MSS1278-683MLD
2 R1, R2, R4 100k
Film Resistor
0603
Panasonic
ERJ3EKF1003V
1
R5
11k
Film Resistor
0603
Panasonic
ERJPA3F3402V
2 VIN, VOUT
–
1.6mm Red Test Eyelets
1.6mm
Keystone
5005
2 GNDIN, GND
–
1.6mm Black Test Eyelets
1.6mm
Keystone
5006
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CISPR 25 Compliance
DDB115R1 EVB User Guide
Input Filter + AP74700AQ + AP68xxxQ/AP6AxxxQ System Solution
Figure 8: Conducted CISPR 25 EMI Plot, Class 5 Limits, 48 VIN, 5 VOUT @ 2.5A, additional 68F filter capacitor added
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Rev. 1
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DDB115R1 EVB User Guide
Input Filter + AP74700AQ + AP68xxxQ/AP6AxxxQ System Solution
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Documents / Resources
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DIODES DDB115R1 EVB Input Filter Automotive Demo Board [pdf] User Guide DDB115R1, DDB115R1 EVB Input Filter Automotive Demo Board, EVB Input Filter Automotive Demo Board, Filter Automotive Demo Board, Automotive Demo Board, Demo Board |