CYUSBS232 User Guide

CYUSBS232
USB-UART LP Reference Design Kit Guide
Doc. # 001-87891 Rev. **
Cypress Semiconductor
198 Champion Court
San Jose, CA 95134-1709
Phone (USA): 800.858.1810
Phone (Intnl): +1.408.943.2600
http://www.cypress.com
Copyrights
© Cypress Semiconductor Corporation, 2013. The information contained herein is subject to change without notice. Cypress
Semiconductor Corporation assumes no responsibility for the use of any circuitry other than circuitry embodied in a Cypress
product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted nor
intended to be used for medical, life support, life saving, critical control or safety applications, unless pursuant to an express
written agreement with Cypress. Furthermore, Cypress does not authorize its products for use as critical components in lifesupport systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The
inclusion of Cypress products in life-support systems application implies that the manufacturer assumes all risk of such use
and in doing so indemnifies Cypress against all charges.
Any Source Code (software and/or firmware) is owned by Cypress Semiconductor Corporation (Cypress) and is protected by
and subject to worldwide patent protection (United States and foreign), United States copyright laws and international treaty
provisions. Cypress hereby grants to licensee a personal, non-exclusive, non-transferable license to copy, use, modify, create
derivative works of, and compile the Cypress Source Code and derivative works for the sole purpose of creating custom software and or firmware in support of licensee product to be used only in conjunction with a Cypress integrated circuit as specified in the applicable agreement. Any reproduction, modification, translation, compilation, or representation of this Source
Code except as specified above is prohibited without the express written permission of Cypress.
Disclaimer: CYPRESS MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARD TO THIS MATERIAL, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE. Cypress reserves the right to make changes without further notice to the materials described
herein. Cypress does not assume any liability arising out of the application or use of any product or circuit described herein.
Cypress does not authorize its products for use as critical components in life-support systems where a malfunction or failure
may reasonably be expected to result in significant injury to the user. The inclusion of Cypress’ product in a life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all
charges.
Use may be limited by and subject to the applicable Cypress software license agreement.
All trademarks or registered trademarks referenced herein are property of the respective corporations.
Flash Code Protection
Cypress products meet the specifications contained in their particular Cypress PSoC Datasheets. Cypress believes that its
family of PSoC products is one of the most secure families of its kind on the market today, regardless of how they are used.
There may be methods, unknown to Cypress, that can breach the code protection features. Any of these methods, to our
knowledge, would be dishonest and possibly illegal. Neither Cypress nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not mean that we are guaranteeing the product as ‘unbreakable’.
Cypress is willing to work with the customer who is concerned about the integrity of their code. Code protection is constantly
evolving. We at Cypress are committed to continuously improving the code protection features of our products.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
2
Contents
Safety Information
5
Regulatory Compliance ...............................................................................................5
General Safety Instructions .........................................................................................6
ESD Protection.................................................................................................6
Handling Boards...............................................................................................6
1. Introduction
1.1
1.2
1.3
1.4
1.5
1.6
1.7
Kit Contents .................................................................................................................7
Getting Started.............................................................................................................8
Additional Resources ...................................................................................................8
Technical Support........................................................................................................9
Document History ........................................................................................................9
Documentation Conventions .......................................................................................9
Abbreviations ...............................................................................................................9
2. Software Installation
2.1
2.2
2.3
14
USB-UART LP Bridge Controller Enumeration..........................................................14
USB-UART LP Bridge Controller Configuration on Windows OS ..............................17
3.2.1 Connecting CYUSBS232 RDK to Cypress USB-Serial Configuration Utility .17
3.2.2 USB Configuration .........................................................................................19
3.2.3 UART Configuration .......................................................................................22
3.2.3.1 Test Procedure for CYUSBS232 RDK Configured as USB-UART .26
3.2.3.2 Throughput Determination ...............................................................27
3.2.4 CYUSBS232 RDK Restore Default Configuration Settings ...........................28
4. Hardware
4.1
4.2
4.3
10
CYUSBS232 RDK Software ......................................................................................10
Install Hardware.........................................................................................................13
Uninstall Software......................................................................................................13
3. Kit Operation
3.1
3.2
7
31
Board Details .............................................................................................................31
Theory of Operation...................................................................................................32
Functional Description ...............................................................................................33
4.3.1 Features .........................................................................................................33
4.3.2 Power-Supply System....................................................................................33
4.3.3 USB Connector ..............................................................................................34
4.3.4 Headers..........................................................................................................34
4.3.5 LEDs ..............................................................................................................35
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Contents
5. Additional Information
5.1
A. Appendix
A.1
A.2
A.3
A.4
37
Using the CYUSBS232 RDK on a Mac OS ...............................................................37
5.1.1 Using CYUSBS232 RDK Board in CDC Mode ..............................................37
5.1.2 Using the CYUSBS232 RDK Board in Vendor Mode.....................................38
39
Schematic ..................................................................................................................39
CY7C65213 USB-UART LP Bridge Controller Design Guidelines ............................40
Troubleshooting Guide ..............................................................................................41
Bill of Materials (BoM)................................................................................................42
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
4
Safety Information
Regulatory Compliance
The CYUSBS232 USB-UART LP kit is intended for use as a development platform for hardware or software in a
laboratory environment. The board is an open-system design, which does not include a shielded enclosure.
This kit may cause interference to other electrical or electronic devices in close proximity. In a domestic
environment, this product may cause radio interference. In such cases, take adequate preventive measures.
Also, do not use this board near any medical equipment or RF devices.
Attaching additional wiring to this product or modifying the product operation from the factory default may affect
its performance and cause interference with other apparatus in the immediate vicinity. If such interference is
detected, suitable mitigating measures must be taken.
The CYUSBS232 contains electrostatic discharge (ESD) sensitive devices.
Electrostatic charges readily accumulate on the human body and any
equipment, and can discharge without detection. Permanent damage may
occur on devices subjected to high-energy discharges. Cypress recommends
proper ESD precautions to avoid performance degradation or loss of
functionality. Store unused CYUSBS232 boards in the protective shipping
package.
End-of-Life/Product Recycling
This kit has an end-of-life cycle after five years from the year of manufacturing
mentioned on the back of the box. Contact your nearest recycler for discarding
the kit.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
5
Safety Information
General Safety Instructions
ESD Protection
ESD can damage boards and associated components. Cypress recommends that you perform procedures only
at an ESD workstation. If an ESD workstation is not available, use appropriate ESD protection by wearing an
antistatic wrist strap attached to the chassis ground (any unpainted metal surface) on the board when handling
parts.
Handling Boards
CYUSBS232 boards are sensitive to ESD. Hold the board only by its edges. After removing the board from its
box, place it on a grounded, static-free surface. Use a conductive foam pad if available. Do not slide the board
over any surface.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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1.
Introduction
Thank you for your interest in the CYUSBS232 USB-UART LP Reference Design Kit (RDK). This
RDK is an easy-to use kit, which showcases the unique features of CY7C65213, Cypress's USBUART LP Bridge Controller. This device is a full-speed USB-UART low-power bridge controller
supporting the 8-pin UART serial interface and USB Implementers Forum (USB-IF) compliant
battery charging detection (BCD) specifications. The controller features the lowest suspend-state
current of 5 uA, and is offered in a 5×5, 32-pin QFN package to meet the dimensional requirements
of portable devices.
1.1
Kit Contents
The CYUSBS232 USB-UART LP RDK includes the following items:
■
CYUSBS232 RDK board
■
Quick start guide
■
USB standard-A to micro-B cable
■
Jumper wires
■
CY7C65213-32LTXI sample silicon chips
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
7
Introduction
Figure 1-1. Kit Contents
1.2
Getting Started
This kit guide helps you get acquainted with the CYUSBS232 RDK. The Software
Installation chapter on page 10 provides step-by-step instructions to install the CYUSBS232 RDK
software. The Kit Operation chapter on page 14 describes how the kit operates and explains how to
configure the CY7C65213 USB-UART LP using the Cypress USB-Serial Configuration Utility. The
Hardware chapter on page 31 discusses the hardware operation. The Additional Information on
page 37 explains how to run the CYUSBS232 RDK on a Mac OS. The Appendix on page 39 provides the schematics, layout, bill of materials (BoM), troubleshooting guidelines, and board layout
design guidelines for the CY7C65213 USB-UART LP controller.
1.3
Additional Resources
Visit the USB-Serial webpage: www.cypress.com/go/usbserial for additional learning resources in
the form of datasheets and application notes.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
8
Introduction
1.4
Technical Support
For assistance, go to our support web page: www.cypress.com/go/support, or contact our customer
support at +1 (800) 541-4736 Ext. 8 (in the USA), or +1 (408) 943-2600 Ext. 8 (International).
1.5
1.6
Document History
Revision
PDF Creation
Date
Origin of
Change
**
09/03/2013
MVTA
Description of Change
Initial version of kit guide
Documentation Conventions
Table 1-1. Document Conventions for Guides
Convention
1.7
Usage
Courier New
Displays file locations, user entered text, and source code:
C:\ ...cd\icc\
Italics
Displays file names and reference documentation.
For example, CYUSBS232UART.cyusb.
[Bracketed, Bold]
Displays keyboard commands in procedures:
[Enter] or [Ctrl] [C]
File > Open
Represents menu paths:
File > Open > New Project
Bold
Displays commands, menu paths, and icon names in procedures:
Click the File icon and then click Open.
Times New Roman
Displays an equation:
2+2=4
Text in gray boxes
Describes cautions or unique functionality of the product.
Abbreviations
The following table lists the abbreviations used in this kit guide: Abbreviation
Definition
CDC
communications device class
CTS
clear to send
DCD
data carrier detect
DSR
data set ready
DTR
data terminal ready
PID
product ID
RDK
reference design kit
RI
ring indicator
RTS
request to send
UART
universal asynchronous receiver transmitter
USB
universal serial bus
VID
vendor ID
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2.
2.1
Software Installation
CYUSBS232 RDK Software
Follow these steps to install the CYUSBS232 RDK software:
1. Download and install the CYUSBS232 RDK software from www.cypress.com/go/CYUSBS232.
The CYUSBS232 RDK software is available in two different formats for download:
a. CYUSBS232 Kit ISO: This file is a complete package, stored in a CD-ROM image format that
can be used to create a CD, or extract using ISO extraction programs, such as WinZip or
WinRAR. This file includes all the required software, utilities, drivers, hardware files, and user
documents.
b. CYUSBS232 Kit Setup: This installation package contains the files related to the kit. It does
not include the Windows installer, Microsoft .NET Framework, and Visual C++ redistributable
packages. If these packages are not on your computer, the installer automatically downloads
and installs them from the Internet.
2. Run cyautorun.exe to start the installation process.
3. Click Install CYUSBS232 RDK to start the installation, as shown in Figure 2-1.
Figure 2-1. Kit Installer Startup Screen
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Software Installation
4. Select the folder to install the CYUSBS232 RDK-related files. Choose the directory and click
Next.
Figure 2-2. Default Path for RDK Installation
5. The CYUSBS232 Kit ISO installer automatically installs the required software, if it is not present
on your computer. The CYUSBS232 Kit Setup installer directs you to download the required
software from the Internet.
6. Select the installation type. The drop-down menu has two options: Typical (installs all the
required features) and Custom. Click Next after you select the installation type.
Figure 2-3. Installation Type Options
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Software Installation
7. Read the Cypress License Agreement and make a selection based on the terms of the license
agreement. Click Next to continue the installation.
Figure 2-4. Cypress License Agreement
8. When the installation begins, a list of packages appears on the installation page. A green check
mark appears against every package after successful installation. If a message from Windows
Security appears, accept the Always trust software from Cypress Semiconductor option and
click Install.
Figure 2-5. Installation Page
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Software Installation
9. Enter your contact information or select the Continue Without Contact Information check box.
Click Finish to complete the CYUSBS232 RDK installation.
Figure 2-6. CYUSBS232 RDK Installation Complete
10.After the installation is complete, the kit contents are available at the following location:
<Install directory>\Cypress\CYUSBS232 RDK\1.0\
2.2
Install Hardware
This kit does not require any additional hardware installation.
2.3
Uninstall Software
You can uninstall the CYUSBS232 RDK software using one of the following methods:
■
Go to Start > All Programs > Cypress > Cypress Update Manager; click the Uninstall button.
■
Go to Start > Control Panel > Programs and Features. Select the CYUSBS232 RDK 1.0 Rev**
program from the list and click the Uninstall/Change button.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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3.
Kit Operation
The CYUSBS232 RDK helps you evaluate the CY7C65213 USB-UART LP bridge controller. The
CYUSBS232 RDK board is designed to work in USB bus-powered mode. Figure 3-1 shows an
image of the board with references to the onboard components.
Figure 3-1. CYUSBS232 RDK Board: Top and Bottom View
Top View
Bottom View
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3.1
USB-UART LP Bridge Controller Enumeration
Connect the CYUSBS232 RDK board to the PC using a USB standard-A to micro-B cable. The
board enumerates as a composite USB device.
Follow these steps for device enumeration:
1. Use the USB standard-A to micro-B cable to connect to the micro-B connector on the board.
2. The PC detects the board and the software driver is automatically bound to the USB device.
Note If the driver installation is unsuccessful, run setup.exe from the following folders with
administrative privileges:
<Install directory>\Cypress\CYUSBS232 RDK\1.0\driver\cyusb3
<Install directory>\Cypress\CYUSBS232 RDK\1.0\driver\cyusbserial
For more information, refer to the Cypress USB-Serial Driver Installation Guide at the following
location: <Install directory>\Cypress\CYUSBS232 RDK\1.0\documentation\
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Kit Operation
Figure 3-2. Install Location for cyusb3 Driver
Figure 3-3. Install Location for cyusbserial Driver
Note If a "Welcome to the Found New Hardware Wizard" message appears, select the Yes, this
time only option and click Next to continue the installation.
4. When the software drivers are successfully bound, the board enumeration is complete. The
board appears as a composite device in the Windows OS device manager. (To launch the device
manager in Win7, go to Start > Control Panel > Device Manager.), as shown in Figure 3-4.
■
USB-Serial Adapter under CypressUSBConsoleWindowsDriver
■
USB Serial Port (COM#) under Ports (COM & LPT)
■
USB-UART LP Vendor MFG under Universal Serial Bus controllers
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Kit Operation
Figure 3-4. CYUSBS232 RDK Board Enumeration as Single UART in Device Manager
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Kit Operation
3.2
USB-UART LP Bridge Controller Configuration on Windows OS
The CY7C65213 USB-UART LP bridge controller on the CYUSBS232 RDK board can be configured
for various USB, UART, and system parameters by using the Cypress USB-Serial Configuration
Utility. The following sections provide detailed descriptions of the device features and configurations.
3.2.1
Connecting CYUSBS232 RDK to Cypress USB-Serial Configuration Utility
Follow these steps to connect the device using the Cypress USB-Serial Configuration Utility:
1. Connect the USB standard-A to micro-B cable to your PC and the micro-B connector on the
board.
2. Run the configuration utility from Start > All Programs > Cypress > CYUSBS232 RDK > USB
Serial Configuration Utility.
For a detailed description about the configuration utility, refer to the USB-Serial Configuration
Utility User Guide at the following location:
<Install directory>\Cypress\CYUSBS232 RDK\1.0\documentation
3. The following figure shows the startup screen of the Cypress USB-Serial Configuration Utility.
Figure 3-5. Configuration Utility Startup Screen
4. Click the Select Target tab. Select the device from the drop-down menu and click Connect.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Kit Operation
Figure 3-6. Configuration Utility Select Target Tab
Note The version number displayed in Figure 3-6 may vary depending on the latest firmware
version on the USB-UART LP bridge controller.
5. A new tab with the connected device's default parameters appears (see Figure 3-7). This tab
allows you to modify the device configuration settings, which you can program into the device.
Figure 3-7. Configuration Utility USB Tab
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Kit Operation
3.2.2
USB Configuration
The USB tab shows the default values of the board’s configurable USB and system parameters.
Follow these steps to view and modify the parameters for the USB configuration:
1. Follow steps 1 to 5 in section 3.2.1 Connecting CYUSBS232 RDK to Cypress USB-Serial
Configuration Utility to connect the board to the Cypress USB-Serial Configuration Utility.
2. Click the USB tab.
Figure 3-8. USB-Serial Configuration Utility USB Tab
3. You can configure these USB parameters using the Cypress USB-Serial Configuration Utility:
a. Vendor identification number (VID)
b. Product identification number (PID)
c. Power mode (bus powered or self powered)
d. bMaxPower
e. RI# and Sleep# (Remote Wake-up and Suspend)
f. Manufacturer string
g. Product string
h. Serial number
■
Vendor ID (VID) and Product ID (PID)
Default value: 0x04B4 and 0x0003
The 2-byte VID and PID must be set in hexadecimal format. The VID and PID fields cannot be
zero or empty. The Cypress VID/PID is programmed by default; to change the VID and PID,
uncheck the Use Cypress VID/PID option. Enter the specific VID and press the [Tab] or [Enter]
key to enable the PID field.
■
Power Mode
Default value: Bus powered
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Kit Operation
The USB power mode can be set either to self-powered or bus-powered mode.
■
bMaxPower
Default Value: 100 mA
The USB device current requirement value can be set from 1 mA to 500 mA in steps of 2 mA
units in bus-powered mode and 0 mA to 500 mA in steps of 2 mA units in self-powered mode.
■
RI# and Sleep#
Default value for RI#: Checked
Default value for Sleep#: GPIO 04
Default value for Power enable: GPIO 03
Note ‘#’ indicates an active-low pin.
Click the Configure button to configure RI#, Sleep#, and Power enable parameters.
Figure 3-9. RI# and Sleep# Configuration Window
The configurable options are:
■
❐
RI#: Ring indicator is an input signal to the device, which is used to wake up the USB host
from suspend state. This signal acts as a wake up source for the USB host. By enabling this
option the device can be used to wake up the USB host from suspend. By checking the Invert
Polarity box, the polarity of the RI# pin can be inverted. On this board, the J7.4 (GPIO
header) is the RI# pin.
❐
Sleep#: The Sleep function is enabled by assigning a GPIO from the drop down menu. When
the USB bus enters the Suspend state, this GPIO gets asserted. For this board, the default
value for the Sleep# pin is GPIO 04. By checking the Invert Polarity box, the polarity of the
assigned GPIO pin can be inverted.
❐
Power enable: The Power enable function is enabled by assigning a GPIO from the dropdown menu. When the USB-UART bridge is configured by the host, this GPIO is asserted. In
bus-powered embedded systems, to meet the USB 2.0 Specification requirements during
unconfigured and suspend state, this pin can be used as a notification to control the power to
the system. For this board, the default value for the Power enable pin is GPIO 03.
Manufacturer string
Default value: Cypress Semiconductor
You can enter the manufacturer string (up to 32 characters) in the text box field.
■
Product string
Default value: USB-UART LP
You can enter the product string (up to 32 characters) in the text box field.
■
Serial number string
Default value: NULL (No serial number string)
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Kit Operation
You can enter the serial number string (up to 32 characters) in the text box field by checking the
check box. If no serial number is required, uncheck the checkbox.
System
The configurable options are:
a. VCC voltage is 3.3 V
b. VCCIO voltage is less than 2 V
c. Enable manufacturing interface
d. I/O Level
e. I/O Mode
f. Program button
g. Disconnect button
■
VCC voltage is 3.3 V
Default status: Unchecked
The RDK is designed only for USB bus-powered operation. This option must always be
unchecked for the RDK. The CY7C65213 device supports VCC voltage range from 3.15 V to
5.25 V.
■
VCCIO voltage is less than 2 V
Default status: Unchecked
The RDK is designed only for 5-V operation. This option must always be unchecked for the
RDK. The CY7C65213 device supports VCCIO voltage range from 1.71 V to 5.5 V.
■
Enable manufacturing interface
Default status: Checked
This option enables an additional vendor class manufacturing mode interface to reprogram
the device.
■
I/O Level
Default value: CMOS
You can set the GPIO logic levels of the device to either CMOS or LVTTL.
■
I/O Mode
Default value: Fast
You can set the GPIO edge transitions of the device to either fast or slow for EMI
considerations. Refer to the GPIO AC Specifications table in the datasheet for additional
details.
■
Program button
After configuring all the device parameters, the updated configuration settings must be
programmed to the device. To program the device, click the Program button.
■
Disconnect button
Click this button to disconnect the RDK from the Configuration utility.
4. After configuring the USB and system parameters, click the Program button to save the changed
USB parameters onto the controller. On successful programming, the "Program Succeeded"
message appears.
5. Click the Disconnect button to disconnect the board from the Configuration Utility.
6. Disconnect and reconnect the USB micro-B cable to the micro-B connector of the RDK to initiate
a power-on-reset of the controller. The controller is reinitialized with the new parameters and the
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Kit Operation
board re-enumerates, as shown in Figure 3-4.
3.2.3
UART Configuration
The RDK board can act as a USB-UART bridge to transfer and receive data between the device and
the PC via terminal communication software, such as Hyperterminal or Tera Term.
Follow these steps to view and modify the parameters for the UART configuration:
1. Follow steps 1 to 5 of section 3.2.1 Connecting CYUSBS232 RDK to Cypress USB-Serial
Configuration Utility to connect the board to the Cypress USB-Serial Configuration Utility.
2. Click the UART tab.
Figure 3-10. Configuration Utility UART Configuration Tab
3. Click the Configure button, as shown in Figure 3-10, to configure the UART parameters.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
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Kit Operation
Figure 3-11. Configuration Utility UART Settings
You can configure the following UART parameters by using the Cypress USB-Serial Configuration
Utility:
a. Baud Rate
b. Type
c. Data Width
d. Stop Bits
e. Parity
f. Invert RTS
g. Invert CTS
h. Invert DTR
i. Invert DSR
j. Invert DCD
k. Invert RI
l. Drop packets on RX error
m. Disable CTS and DSR pull-up during suspend
■
Baud Rate
Default value: 115200
You can set the baud rate for the UART in an editable drop-down combo box that lists the
predefined, standard baud rates. You can also enter a specific baud rate in the combo box. The
minimum and maximum baud rates supported by this board are 300 bps and 3 Mbps,
respectively.
■
Type
Default value: 8 pin
You can set the UART type to:
a. 2 pin (RXD and TXD pins)
b. 4 pin (RXD, TXD, RTS#, and CTS# pins)
c. 6 pin (RXD, TXD, RTS#, CTS#, DSR#, and DTR# pins)
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Kit Operation
d. 8 pin (RXD, TXD, RTS#, CTS#, DSR#, DTR#, RI#, and DCD#)
■
Data Width
Default value: 8 bits
You can set the UART Data width to either 7 bits or 8 bits.
■
Stop Bits
Default value: 1 bit
You can set the number of UART stop bits to either 1 bit or 2 bits.
■
Parity
Default value: None
You can set the parity for the UART data transfer to either None, Odd, Even, Mark, or Space.
■
Invert RTS
Default value: Unchecked
By checking this option, the polarity of the RTS line can be inverted.
■
Invert CTS
Default value: Unchecked
By checking this option, the polarity of the CTS line can be inverted.
■
Invert DTR
Default value: Unchecked
By checking this option, the polarity of the DTR line can be inverted.
■
Invert DSR
Default value: Unchecked
By checking this option, the polarity of the DSR line can be inverted.
■
Invert DCD
Default value: Unchecked
By checking this option, the polarity of the DCD line can be inverted.
■
Invert RI
Default value: Unchecked
By checking this option, the polarity of the RI line can be inverted.
■
Drop packets on RX error
Default value: Unchecked
This parameter defines the behavior of the UART when an error is detected in the packet
received (RX packet/byte). When this option is selected, the data packet/byte in the RX buffer is
discarded.
■
Disable CTS and DSR pull-up during suspend
Default value: Checked
In an embedded system, this parameter can be checked to reduce system current consumption
during Suspend state. This parameter disables the CTS and DSR pull-up resistors in the
Suspend state to meet USB 2.0 Specification current requirements.
4. After the UART configuration is complete, click OK to close the Configure UART Settings
window and return to the UART tab.
5. Select CDC as the protocol in the drop-down menu.
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24
Kit Operation
6. After configuring the UART interface, click the Program button to save the changed UART
settings onto the controller. On successful programming, the "Program Succeeded" message
appears.
7. Click the Disconnect button to disconnect the board from the Configuration Utility.
8. Disconnect and reconnect the USB micro-B cable to the micro-B connector on the RDK to initiate
a power-on-reset of the controller. The controller is reinitialized with the new parameters and the
board re-enumerates, as shown in Figure 3-12.
Figure 3-12. CYUSBS232 RDK Enumeration as USB-UART in Device Manager
9. The Cypress USB-Serial Configuration Utility is displayed, as shown in Figure 3-6.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
25
Kit Operation
3.2.3.1
Test Procedure for CYUSBS232 RDK Configured as USB-UART
1. To test the functionality of the UART interface, you can perform a quick loopback test by
connecting the jumper wires as follows:
❐
J7.8 - J7.5 (TXD to RXD)
❐
J7.6 - J7.1 (RTS# to CTS#)
❐
J7.7 - J7.3 (DTR# to DSR#)
Figure 3-13. Connection for Loopback Test
2. Open an instance of a serial emulation terminal, such as Tera Term, which can be installed from
the following location:
<Install directory>/cypress/CYUSBS232 RDK/1.0/teraterm
3. In the Tera Term: New Connection window, click Serial and select USB-Serial Port (COM#), as
shown in Figure 3-14. Click OK. The screen appears, as shown in Figure 3-15.
Note To change the UART parameters, go to Setup > Serial port in the Tera Term terminal.
Figure 3-14. Tera Term Connection
4. Connecting TXD and RXD enables the data to flow from UART transmitter to receiver, which gets
displayed on the same terminal, as shown in Figure 3-15. This test procedure validates the
functioning of USB-UART bridge. If the local echo option is enabled, then the typed in data
appears twice on the terminal.
Note To enable the local echo option, go to Setup > Terminal. In the Tera Term: Terminal Setup
window, check the local echo box.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
26
Kit Operation
Figure 3-15. Tera Term Application: Loopback Test Output (local echo enabled)
3.2.3.2
Throughput Determination
Throughput is the average rate of successful data transfer over the UART channel. It is measured in
bits/second. A PC application can be used to determine the throughput of an USB-UART LP bridge
controller. The CY7C65213 device supports 3 Mbps, but the actual reported throughput on a PC
application (Tera Term) will be less than 3 Mbps, usually around 1 Mbps, due to protocol overhead
and PC application latency.
Follow these steps to determine the throughput of the USB-UART LP bridge controller:
1. In the Tera Term window, go to Setup > Serial Port:
a. Enter ‘3000000’ in the Baud rate drop-down combo box.
b. Select Hardware in the Flow control drop-down menu.
c. Click OK
2. Go to Setup > Terminal > Receive and select CR+LF. Click OK to continue.
3. Go to File menu. Select Send File from the drop-down menu, as shown in Figure 3-16.
Figure 3-16. Sending the File
4. Select a file to be sent through USB Serial Port (COM#). After the file is selected, the data transfer starts and the window is displayed, as shown in Figure 3-17.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
27
Kit Operation
5. Number of bytes transferred per second determines throughput. The "Tera Term :Send File" window shows effective data throughput in Bytes/sec; multiply this value by 8 to get the throughput in
bits/sec. Again, multiply this value by 2 to get the unidirectional throughput.
Figure 3-17. Throughput Determination
3.2.4
CYUSBS232 RDK Restore Default Configuration Settings
The CYUSBS232 RDK board features the CY7C65213 USB-UART LP bridge controller, which is
factory-programmed with default UART parameters. You can reconfigure the device using the
Cypress USB-Serial Configuration Utility to meet specific requirements that overwrites the factory
configuration.
To restore the board to the default factory settings, follow these steps:
1. Follow steps 1 to 5 in section 3.2.1 Connecting CYUSBS232 RDK to Cypress USB-Serial
Configuration Utility to connect the board to the Cypress USB-Serial Configuration Utility.
2. Click File > Open Configuration from > Disk, as shown in Figure 3-18.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
28
Kit Operation
Figure 3-18. Select Configuration Window
3. Select the default configuration file from the following location:
<Install directory>\Cypress\CYUSBS232 RDK\1.0\default factory
settings\CYUSBS232UART.cyusb
Figure 3-19. Select Default Configuration File Window
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
29
Kit Operation
4. After successfully loading the default configuration file, the message “Configuration settings were
successfully loaded from the file” appears. Click OK to continue.
Figure 3-20. Load Configuration
5. Click Program to update the configuration settings. On successful programming, the "Program
Succeeded” message appears.
Disconnect and reconnect the USB micro-B cable to the micro-B connector on the RDK to initiate
a power-on-reset of the controller.
6. The Cypress USB-Serial Configuration Utility is displayed as shown in Figure 3-6, and the board
enumerates as shown in Figure 3-4.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
30
4.
4.1
Hardware
Board Details
The CYUSBS232 RDK board consists of the following components:
■
CY7C65213 USB-UART LP bridge controller
■
Power-supply system
■
USB connector
■
Headers
■
LEDs
Figure 4-1. CYUSBS232 RDK Board
Top View
Bottom View
.JDSP#
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64#6"35-1
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7#64
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(1*0
354
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59%
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CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
31
Hardware
4.2
Theory of Operation
This section provides the block-level description of the CYUSBS232 RDK board.
Figure 4-2. Hardware Block Diagram
Power
LED
R e g u la to r
J7
3 .3 V
CON1
VBUS
D+
USB
C o n n e cto r
UART
S ig n a ls
V C C IO
VCC
USB
UART LP
TX and RX
a ctivity L E D s
DGND
G P IO s
J6
The CYUSBS232 RDK board features the CY7C65213 full-speed USB-UART LP bridge controller
that offers a configurable UART interface. This device is a fixed-function controller, which does not
require any firmware development. The USB, UART, and system parameters of the controller can be
modified using the easy-to-use Cypress USB-Serial Configuration Utility.
The CYUSBS232 RDK board is powered from the USB by a USB standard-A to micro-B cable. This
input voltage is regulated by an LDO regulator to 3.3 V and connected to the USB-UART LP bridge
controller. All the UART pins and GPIO signals from the USB-UART LP bridge are brought out to the
headers (J6 and J7) to allow connecting and testing the functionality easily. You can also interface
any type of UART legacy device to these headers to convert it to an USB device.
The CYUSBS232 RDK board has a power LED, TX activity LED, and RX activity LED. LED
functions are explained in section 4.3.5 LEDs.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
32
Hardware
4.3
Functional Description
This RDK uses the CY7C65213 USB-UART LP bridge controller, which is a full-speed USB
controller that enables seamless PC connectivity by upgrading UART-based legacy devices to the
USB with a minimum number of components. This device includes a UART, an internal regulator, an
internal oscillator, and 512 bytes of flash in a 32-pin QFN package. For more information, refer to the
USB-Serial web page at www.cypress.com/go/usbserial and the USB-Serial datasheet.
4.3.1
Features
■
■
USB 2.0-certified, full-speed (12 Mbps)
❐
Supports communication driver class (CDC), personal health care device class (PHDC), and
vendor-specific drivers
❐
BCD compliant with USB Battery Charging Specification, Rev. 1.2 (Peripheral Detect only)
❐
Integrated USB termination resistors
Single-channel configurable UART interface
❐
Data rates up to 3 Mbps
❐
256 bytes for each transmit and receive buffer
❐
Data format:
7 to 8 data bits
1 to 2 stop bits
4.3.2
❐
No parity, even, odd, mark, or space parity
❐
Supports parity, overrun, and framing errors
❐
Supports flow control using Clear To Send (CTS), Request To Send (RTS), Data Terminal
Ready (DTR), and Data Set Ready (DSR)
Power-Supply System
The CYUSBS232 RDK board is designed to operate in USB bus-powered mode. The onboard low
drop-out regulator (LDO) provides the 3.3 V required for the bridge controller.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
33
Hardware
4.3.3
USB Connector
A USB standard micro-B connector is used in the board. The shield of this connector is connected to
the ground. Two inductors (L1 and L2) are placed on the VBUS and GND pins to reduce noise from
the power supply lines.
Figure 4-3. USB to UART Schematic
VBUS
CON1
VBUS
DM
DP
GND
SHIELD1
SHIELD2
1
2
L1
USB_DM
3
USB_DP
4
5
6
+
C4
1uF
L2
USB - MICRO B
DX4R005J91R1500
JAE Electronics
4.3.4
Headers
All the device signals (UART and GPIO) are available for external connectivity via the headers J7
and J6. The following tables provide the header details.
Table 4-1. J7 (UART Signals)
Header Pin #
Name
J.7.1
CTS#
J.7.2
DCD#
J.7.3
DSR#
J.7.4
RI#
J.7.5
RXD
J.7.6
RTS#
J.7.7
DTR#
J.7.8
TXD
J.7.9
Not Connected
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
34
Hardware
Table 4-2. J6 (GPIO Header)
GPIO Header Pin #
4.3.5
Name
J.6.1
VBUS
J.6.2
GND
J.6.3
GND
J.6.4
VCCIO_OUT
J.6.5
GPIO2
J.6.6
GPIO4
J.6.7
GPIO3
J.6.8
GPIO1 (RXLED)
J.6.9
GPIO0 (TXLED)
LEDs
The CYUSBS232 RDK board has three LEDs:
■
D1: This LED will turn on to indicate that the board is powered.
■
D2: This LED is connected to GPIO0 of the device. It will turn on to indicate the data transfer on
the TXD pin of the UART.
■
D3: This LED is connected to GPIO1 of the device. It will turn on to indicate the data transfer on
the RXD pin of the UART.
Figure 4-4. D1 LED (VBUS Indication)
3
C3
U1
1
0.1uF
3 VBUS
VCCIO
R5
VBUS
1k
D1
C1
USB_DP
USB_DM
19
14
15
LED
VCC
USBDP
USBDM
25
26
27
28
29
NC0
NC1
NC2
NC3
NC
0.1uF
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
35
Hardware
Figure 4-5. D2 and D3 LEDs (TXD and RXD Activity Indication)
VCCIO_out
C2
RI#
DSR#
DCD#
CTS#
RESET#
DTR#
RTS#
TxD
RxD
CBUS
Serial UART
1uF
GPIO0
GPIO1
GPIO2
GPIO3
GPIO4
3
6
7
8
18
31
32
30
2
22
21
10
11
9
RI#
DSR#
DCD#
CTS#
RESET
DTR#
RTS#
TxD
RxD
R7
R6
1k
1k
D2
D3
LED
LED
GPIO0
GPIO1
GPIO2
GPIO3
GPIO4
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
36
5.
Additional Information
5.1
Using the CYUSBS232 RDK on a Mac OS
5.1.1
Using CYUSBS232 RDK Board in CDC Mode
The CY7C65213 USB-UART LP bridge controller automatically binds to the AppleUSBCDC driver,
which is the CDC class driver in Mac OS X.
Follow these steps to use the CDC mode for Cypress USB-UART LP bridge on a Mac OS:
1. Connect the CYUSBS232 RDK board to Mac. The Mac CDC class driver (AppleUSBCDC)
automatically binds to the device. After the driver successfully binds, a device node is created as
/dev/tty.usbmodem<number>.
2. Install a standard terminal emulator, such as SerialTools to test the UART functionality of the
device. SerialTools is a free application available in the Apple App Store.
3. Open the SerialTools application. In the Serial Port field, select the Cypress USB-UART LP
bridge device node created in step 1.
Figure 5-1. Connecting USB-UART Bridge in SerialTools
4. Configure the UART parameters, such as baud rate, stop bits, data width, and parity.
5. For simple loopback tests, short the RXD and TXD pins on the RDK.
6. Click Connect to start communicating with the device.
7. Type Cypress in the text field. Because the local echo is always enabled in the SerialTools
application, the entered characters will be displayed twice.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
37
Additional Information
Figure 5-2. SerialTools Application: Loopback Test Output
5.1.2
Using the CYUSBS232 RDK Board in Vendor Mode
Follow these steps to use the CYUSBS232 RDK board in the vendor mode on a Mac OS.
1. Download the latest USB-Serial SDK for Mac from www.cypress.com/go/usbserial.
2. Follow the steps listed in the README file provided in the software development kit (SDK) to
compile and install the library.
3. When the library is installed, execute the test utility (CyUSBSerialTestUtility) to verify
communication with the CYUSBS232 RDK board.
4. For a detailed API description, refer to CyUSBSerial API Documentation.pdf in the <install
directory>/common/doc folder of the SDK.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
38
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
A
B
C
4
5
6
3
1
2
1
BCD1
0.1uF
C1
VBUS
3 VBUS
2
TEST POINT
LED
D1
1k
R5
L1
L2
5
TEST POINT
BCD0
USB_DP
USB_DM
25
26
27
28
29
13
12
5
19
14
15
0.1uF
C3
NC0
NC1
NC2
NC3
NC4
BCD1
BCD0
VBD
VCC
USBDP
USBDM
U1
VCCIO_out
USB_DP
USB_DM
SW2
0 ohm 0603
DEFAULT_OPTION = 1&2
VCCIO
USB - MICRO B
DX4R005J91R1500
JAE Electronics
GND
SHIELD1
SHIELD2
1
2
3
D
DP
VBUS
DM
CON1
1
VBUS
+
C4
1uF
CY7C65213
4
4
GPIO0
GPIO1
GPIO2
GPIO3
GPIO4
RI#
DSR#
DCD#
CTS#
RESET#
DTR#
RTS#
TxD
RxD
1uF
C2
VCCD
Serial UART
5
1
1
VCCIO
NC
23
NC
16
VCCD
GND
AGND
17
24
GND
20
CBUS
GND
4
EPAD
33
22
21
10
11
9
3
6
7
8
18
31
32
30
2
GPIO0
GPIO1
GPIO2
GPIO3
GPIO4
RI#
DSR#
DCD#
CTS#
RESET
DTR#
RTS#
TxD
RxD
LED
LED
3
1k
D3
1k
R6
D2
R7
VCCIO_out
RESET
0.1uF
C6
3
2
1
VBUS
3
Date:
Size
A
Title
Vadj
Vout
4
5
1uF
C5 +
CTS#
DCD#
DSR#
RI#
RxD
RTS#
DTR#
TxD
3
SW3
3
VBUS
GND
GND
VCCIO_OUT
GPIO2
GPIO4
GPIO3
GPIO1
GPIO0
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
2
1
Sheet
2
1
of
CY7C65213 DEVICE CONNECTION
Wednesday, August 28, 2013
2
630-60096-01
CYUSBS232 USB-UART LP BOARD
2
1
CON9
J7
CON9
J6
0 ohm 0603
2
1M
R2
VCCIO
1
CYPRESS SEMICONDUCTOR © 2013
TC1070
GND
SHDn
Vin
U3
2
Document Number
2
3
1
SW1
0 ohm 0603
DEFAULT_OPTION =
NO LOAD
4.7k
R1
VBUS
1
2
Rev
03
562k
R3
A
B
C
D
A.1
3
A.
Appendix
Schematic
The CYUSBS232 RDK board schematic is available at www.cypress.com/go/CYUSBS232.
Figure A-1. CYUSBS232 Schematic
39
A.2
CY7C65213 USB-UART LP Bridge Controller Design Guidelines
This section explains the guidelines for a board design using the CY7C65213 USB-UART LP bridge
controller:
■
The CY7C65213 silicon can operate from 1.71 V to 5.5 V.
■
The VCCD pin should be shorted to the VCCIO pin when an operating voltage (VCCIO) is from
1.71 V to 1.89 V.
■
A 1-µF decoupling capacitor should be connected between the VCCD pin and ground when the
operating voltage is greater than 2 V.
■
Decoupling capacitors (decap) must be placed close to VCCIO pins. Place the C3 decap close to
VCCIO pin and C1 decap close to VCC pin; C10 is the 1-µF capacitor placed close to the VCCD
pin.
Figure A-2. Decoupling Capacitor Placement
■
Output current requirement of the LDO should be a minimum of 1 A.
■
Power traces should be routed with minimum of 20 mils trace width
■
The CY7C65213 USB-UART LP bridge controller has an exposed pad (EPad) in the bottom that
must be connected to the GND pad on the PCB.
■
An active low 1-µs pulse width is required to reset the CY7C65213 USB-UART LP bridge controller.
■
USB traces (DP/DM) should be routed with a 90- impedance.
■
USB differential traces (DP/DM) should be routed with a solid reference plane.
■
In the BCD interface, the bus-detect signal should be connected with a resistor divider network
from VBUS. Refer to the Application Examples section in the CY7C65213 datasheet for recommended values.
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
40
A.3
Troubleshooting Guide
Problem
Possible Cause
USB cable is not connected to
the PC.
Possible Solution
Connect the USB cable.
The CYUSBS232 RDK board
PC does not power up the USB
Connect on a different USB port.
does not power up in bus-pow- port.
ered mode. Power on LEDs, D2
Use a different USB cable. Or use the self(5 V) and D4 (3.3 V) do not light
USB cable is faulty
powered mode and connect the 5-V DC
up.
power supply provided with the kit.
Power on LED is faulty.
Check if the voltage on the D2 LED is 5 V.
Run setup.exe in the following location:
The CYUSBS232 RDK board
does not enumerate.
USB driver is not bound to the
RDK.
a.<Install_directory>\
Cypress\CYUSBS232
RDK\1.0\driver\cyusb3
b.<Install_directory>\
Cypress\CYUSBS232
RDK\1.0\driver\cyusbserial
UART does not work.
UART is not properly configured.
Load CYUSBS232UART.cyusb supplied
with the kit. See 3.2.4 CYUSBS232 RDK
Restore Default Configuration Settings on
page 28. Assert power-on-reset to the
RDK (remove and reconnect the USB
micro-B cable to the micro-B connector on
the RDK).
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
41
A.4
Bill of Materials (BoM)
No. Qty.
Reference
Description
Manufacturer
Manufacturer Part No.
1
1
600-60096-01
REV**
PCB, CYUSBS232 USB-Serial
Board
Cypress Semiconductor
600-60096-01 REV**
2
1
CON1
CONN RCPT 5POS R/A MICRO
USB
JAE Electronics
DX4R005J91R1500
3
3
C1,C3,C6
CAP CER 0.1UF 16V 10% X7R
0402
TDK Corporation
C1005X7R1C104K050BC
4
1
C2
CAP CER 1UF 16V 10% X5R
0402
TDK Corporation
C1005X5R1C105K050BC
5
2
C4,C5
CAP CER 1UF 10V 10% X7R
0603
TDK Corporation
C1608X7R1A105K080AC
6
3
D1,D2,D3
LED GREEN RECT CLEAR 0603 Lite-On Inc
LTST-C193KGKT-5A
7
2
J6,J7
CONN HEADER 9POS .100"
SGL GOLD
Samtec Inc
TSW-109-16-G-S
8
2
L1,L2
FERRITE CHIP 220 OHM 2A
0805
Murata Electronics
BLM21PG221SN1D
9
1
R1
RES 4.70K OHM 1/10W 1% 0402 Panasonic Electronic
SMD
Components
ERJ-2RKF4701X
10
1
R2
RES 1.00M OHM 1/10W 1% 0402 Panasonic Electronic
SMD
Components
ERJ-2RKF1004X
11
1
R3
RES 562K OHM 1/10W 1% 0402
SMD
Panasonic Electronic
Components
ERJ-2RKF5623X
12
3
R5,R6,R7
RES 1.00K OHM 1/10W 1% 0402 Panasonic Electronic
SMD
Components
ERJ-2RKF1001X
13
3
SW1,SW2,SW3
RES 0.0 OHM 1/10W JUMP 0603 Panasonic Electronic
SMD
Components
ERJ-3GEY0R00V
14
1
U1
USB-Serial
Cypress Semiconductor
CY7C65213-32LTXI
15
1
U3
IC REG LDO ADJ 50MA
SOT23A-5
Microchip
TC1070VCT713
CYUSBS232 USB-UART LP Reference Design Kit Guide, Doc. # 001-87891 Rev. **
42