ROHM BD9S209NUX-C Evaluation Board User Guide

: September 23, 2024
: ROHM

Table of Contents

BD9S209NUX-C Evaluation Board
Specifications
Product Usage Instructions
Operating Procedure
- Frequently Asked Questions (FAQ)
Q: Can the BD9S209NUX-C Evaluation Board support hot plug?
Q: What is the minimum and maximum input voltage supported by
Q: What is the maximum efficiency of the BD9S209NUX-C at an
- Read User Manual Online (PDF format)
- Download This Manual (PDF format)

BD9S209NUX-C Evaluation Board

Specifications

Input Voltage: 2.7V – 5.5V
Output Voltage: 0.8V – VIN
Output Current Range: Up to 2.0A
Switching Frequency: 2.2MHz
Maximum Efficiency: Up to 87.32%

Product Usage Instructions

Operating Procedure

Turn off EN and connect the GND terminal of the power supply to
the GND terminal of the Evaluation Board.
Connect the power supply to the VIN terminal of the Evaluation
Board.
Connect the load to the Evaluation Board’s VOUT and GND
terminals. If using an electronic load, ensure it is turned
off.
Connect a voltmeter to the Evaluation Board’s VOUT and GND
terminals.
Turn on the power supply of VIN and switch on the EN
terminal.
Ensure the voltmeter is set to measure voltage.
Turn on the electronic load. Note: This Evaluation Board does
not support hot plug, so avoid performing hot plug tests.

Frequently Asked Questions (FAQ)

Q: Can the BD9S209NUX-C Evaluation Board support hot plug?

A: No, the Evaluation Board does not support hot plug. Avoid
performing hot plug tests.

Q: What is the minimum and maximum input voltage supported by

the BD9S209NUX-C?

A: The BD9S209NUX-C supports an input voltage range of 2.7V to
5.5V.

Q: What is the maximum efficiency of the BD9S209NUX-C at an

output voltage of 1.2V?

A: The BD9S209NUX-C can achieve a maximum efficiency of up to
87.32% at an output voltage of 1.2V.

User’s Guide

Secondary Buck DC/DC Converter
Single Synchronous Buck DC/DC Converter For Automotive BD9S209NUX-C Evaluation Board
BD9S209NUX-TSB-001 (5.0V Input, 1.2V Output, 2A)

Introduction
This user’s guide will provide the necessary steps to operate the Evaluation Board of ROHM’s BD9S209NUX-C Buck DC/DC converter. This includes the external parts, operating procedures and application data.

Description
This Evaluation Board was developed for ROHM’s single Synchronous buck DC/DC converter BD9S209NUX-C. It is a synchronous buck DC/DC converter with built-in low On Resistance power MOSFETs. BD9S209NUX-C accepts a power supply input range of 2.7 V to 5.5 V and generates a maximum output current of 2 A. Small inductor is applicable due to high switching frequency of 2.2 MHz. It is a current mode control DC/DC Converter and features high-speed transient response. It has a built-in phase compensation circuit. Applications can be created with a few external components.
Application
Automotive Equipment Other Electronic Equipment

Recommended Operating Conditions
Table 1. Recommended Operating Conditions

Parameter

Min

Typ

Max

Units

Conditions

Input Voltage

2.7

–

5.5

V

Output Voltage (Note1)

0.8

–

VIN

V

Output Current Range

–

2.0

A

Switching Frequency

–

2.2

–

MHz

Maximum Efficiency (Vo = 1.2 V)

–

87.32

–

%

VIN = 3.3 V, Io = 0.4A, Ta = 25 °C

(Note 1) Although the minimum output voltage is configurable up to 0.8 V, it may be limited by the SW min ON pulse width. SW Minimum ON Time that BD9S209NUX-C can output stably in the entire load range is 80 ns. Use the value to calculate the input

and

output

conditions

that

satisfy

the

equation

of

80

[ns]

×

No.67UG037E Rev.001 Apr.2024

BD9S209NUX-C Evaluation Board

User’s Guide

Figure 1. Evaluation Board Top View
Evaluation Board Schematic

Figure 2. Circuit Diagram
Operating Procedure
1. Turn off EN and connect the GND terminal of the power supply to the GND terminal of Evaluation Board. 2. Connect power supply to the VIN terminal of the Evaluation Board. 3. Connect the load to the Evaluation Board’s VOUT and GND terminals. When using an electronic load, connect with the
load turned off. 4. Connect a voltmeter to the Evaluation Board’s VOUT and GND terminals. 5. Turn on the Power supply of VIN. Turn ON the switch of EN terminal. 6. Make sure that the voltmeter is set to measure voltage. 7. Turn on the electronic load. (Caution) This Evaluation Board does not support hot plug. Do not perform hot plug test. (Note) If EN = High (EN short to VIN) before Power ON, the turn ON and turn OFF is controlled by VIN only.

No.67UG037E Rev.001 Apr.2024

BD9S209NUX-C Pin Configuration

User’s Guide

Parts list

No L1 COUT1
CIN1 R100
R1 (Note1)
R2 (Note1)
R3 CSS C1 COUT2 CIN2 CF1 CF2 F1 CF3

Package 2520 2012 2012 0603
0603
0603 –
1005 –

No L1 COUT1 CIN1 R100 R1 (Note1) R2 (Note1) R3 CSS C1 COUT2 CIN2 CF1 CF2 F1 CF3

Package 2520 2012 2012 0603
0603
0603 –
1005 –

Figure 3. Pin Configuration

Table 2. Parts List (VOUT=1.0V, VIN=5.0V, 3.3V)

Parameters 0.68 H
10 F, X7R, 10 V

Part Name (Series) DFE252012PD-R68M GCM21BR71A106KE21

10 F, X7R, 10 V SHORT
7.5 k, 1 %, 1/20 W

GCM21BR71A106KE21 –
MCR006 series

Type Inductor Ceramic Capacitor
Ceramic Capacitor –
Chip Resistor

Manufacturer Murata Murata
Murata –
ROHM

30 k, 1 %, 1/20 W

MCR006 series

Chip Resistor

ROHM

100 k, 1 %, 1/20 W –
100 pF, C0G, 50 V –

MCR006 series –
GCM1555C1H101JA16 –

Chip Resistor –
Ceramic Capacitor –

ROHM –
Murata –

Table 3. Parts List (VOUT=1.2V, VIN=5.0V, 3.3V)

Parameters 0.68 H
10 F, X7R, 10 V 10 F, X7R, 10 V
SHORT 10 k, 1 %, 1/20 W

Part Name (Series) DFE252012PD-R68M GCM21BR71A106KE21 GCM21BR71A106KE21
MCR006 series

Type Inductor Ceramic Capacitor Ceramic Capacitor
Chip Resistor

Manufacturer Murata Murata Murata ROHM

20 k, 1 %, 1/20 W

MCR006 series

Chip Resistor

ROHM

100 k, 1 %, 1/20 W –
100 pF, C0G, 50 V –

MCR006 series –
GCM1555C1H101JA16 –

Chip Resistor –
Ceramic Capacitor –

ROHM –
Murata –

No.67UG037E Rev.001 Apr.2024

BD9S209NUX-C

User’s Guide

No L1 COUT1 CIN1 R100 R1 (Note1) R2 (Note1) R3 CSS C1 COUT2 CIN2 CF1 CF2 F1 CF3

Package 2520 2012 2012 0603
0603
0603 –
1005 –

No L1 COUT1 CIN1 R100 R1 (Note1) R2 (Note1) R3 CSS C1 COUT2 CIN2 CF1 CF2 F1 CF3

Package 2520 2012 2012 0603
0603
0603 –
1005 –

Table 4. Parts List (VOUT=1.5V, VIN=5.0V, 3.3V)

Parameters 0.68 H
10 F, X7R, 10 V 10 F, X7R, 10 V
SHORT 16 k, 1 %, 1/20 W

Part Name (Series) DFE252012PD-R68M GCM21BR71A106KE21 GCM21BR71A106KE21
MCR006 series

Type Inductor Ceramic Capacitor Ceramic Capacitor
Chip Resistor

Manufacturer Murata Murata Murata ROHM

18 k, 1 %, 1/20 W

MCR006 series

Chip Resistor

ROHM

100 k, 1 %, 1/20 W –
100 pF, C0G, 50 V –

MCR006 series –
GCM1555C1H101JA16 –

Chip Resistor –
Ceramic Capacitor –

ROHM –
Murata –

Table 5. Parts List (VOUT=1.8V, VIN=5.0V, 3.3V)

Parameters 1.0 H
10 F, X7R, 10 V 10 F, X7R, 10 V
SHORT
30 k, 1 %, 1/20 W

Part Name (Series) TFM252012ALMA1R0M GCM21BR71A106KE21 GCM21BR71A106KE21
MCR006 series

Type Inductor Ceramic Capacitor Ceramic Capacitor
Chip Resistor

Manufacturer TDK
Murata Murata
ROHM

24 k, 1 %, 1/20 W

MCR006 series

Chip Resistor

ROHM

100 k, 1 %, 1/20 W –
100 pF, C0G, 50 V –

MCR006 series –
GCM1555C1H101JA16 –

Chip Resistor –
Ceramic Capacitor –

ROHM –
Murata –

No.67UG037E Rev.001 Apr.2024

BD9S209NUX-C

User’s Guide

No L1 COUT1 CIN1 R100 R1 (Note1) R2 (Note1) R3 CSS C1 COUT2 CIN2 CF1 CF2 F1 CF3

Package 2520 2012 2012 0603
0603
0603 –
1005 –

Table 6. Parts List (VOUT=3.3V, VIN=5.0V)

Parameters 1.0 H
10 F, X7R, 10 V 10 F, X7R, 10 V
SHORT 75 k, 1 %, 1/20 W

Part Name (Series) TFM252012ALMA1R0M GCM21BR71A106KE21 GCM21BR71A106KE21
MCR006 series

24 k, 1 %, 1/20 W

MCR006 series

100 k, 1 %, 1/20 W –
100 pF, C0G, 50 V –

MCR006 series –
GCM1555C1H101JA16 –

(Note

VOUT

=

1+2 2

0.8

[V]

Type Inductor Ceramic Capacitor Ceramic Capacitor
Chip Resistor

Manufacturer TDK
Murata Murata
ROHM

Chip Resistor

ROHM

Chip Resistor –
Ceramic Capacitor –

ROHM –
Murata –

(Note 2) CSS, COUT2, CIN2, CF1, CF2, F1, CF3 patterns are only optional. They can be utilized for adjusting the

characteristics constants.

(Note 3) If the recommended parts on tables 2, 3, 4, 5 and 6 are not available anymore due to end of production, different parts

will be used on the test board because the end of production parts are deprecated.

No.67UG037E Rev.001 Apr.2024

BD9S209NUX-C

Board Layout

Evaluation Board PCB information Number of Layers Material

4

FR4 High TG

Board Size 114.3mm x 76.2mm x
1.6mm

The layout of BD9SXXXNUX-C series board is shown below.

User’s Guide
Copper Thickness 2oz(70m) / 1oz (35m) / 1oz (35m) / 2oz(70m)

Figure 4. Top Layer Layout

Figure 5. Middle1 Layer Layout

Figure 6. Middle2 Layer Layout

5 Figure 7. Bottom Layer Layout

Figure 9. Bottom Parts Placement

No.67UG037E Rev.001

6/7

Apr.2024

BD9S209NUX-C

Revision History

Date 16.Apr.2024

Revision Number
001

New Release

Description

User’s Guide

7/7

No.67UG037E Rev.001 Apr.2024

Notice
Notice

The information contained in this document is intended to introduce ROHM Group (hereafter referred to asROHM) products. When using ROHM products, please verify the latest specifications or datasheets before use.
ROHM products are designed and manufactured for use in general electronic equipment and applications (such as Audio Visual equipment, Office Automation equipment, telecommunication equipment, home appliances, amusement devices, etc.) or specified in the datasheets. Therefore, please contact the ROHM sales representative before using ROHM products in equipment or devices requiring extremely high reliability and whose failure or malfunction may cause danger or injury to human life or body or other serious damage (such as medical equipment, transportation, traffic, aircraft, spacecraft, nuclear power controllers, fuel control, automotive equipment including car accessories, etc. hereafter referred to as Specific Applications). Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any damages, expenses, or losses incurred by you or third parties arising from the use of ROHM Products for Specific Applications.
Electronic components, including semiconductors, can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate safety measures including but not limited to fail-safe design against physical injury, and damage to any property, which a failure or malfunction of products may cause.
The information contained in this document, including application circuit examples and their constants, is intended to explain the standard operation and usage of ROHM products, and is not intended to guarantee, either explicitly or implicitly, the operation of the product in the actual equipment it will be used. As a result, you are solely responsible for it, and you must exercise your own independent verification and judgment in the use of such information contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses, or losses incurred by you or third parties arising from the use of such information.
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The technical information and data described in this document, including typical application circuits, are examples only and are not intended to guarantee to be free from infringement of third parties intellectual property or other rights. ROHM does not grant any license, express or implied, to implement, use, or exploit any intellectual property or other rights owned or controlled by ROHM or any third parties with respect to the information contained herein.
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All information contained in this document is current as of the date of publication and subject to change without notice. Before purchasing or using ROHM products, please confirm the latest information with the ROHM sales representative.
ROHM does not warrant that the information contained herein is error-free. ROHM shall not be in any way responsible or liable for any damages, expenses, or losses incurred by you or third parties resulting from errors contained in this document.

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