Cypress CY8C28623-24LTXI User manual

CY3280-28XXX Universal CapSense®
Controller Development Kit Guide
Spec. # 001-57457 Rev. **
Cypress Semiconductor
198 Champion Court
San Jose, CA 95134-1709
Phone (USA): 800.858.1810
Phone (Intnl): 408.943.2600
http://www.cypress.com
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2 CY3280-28XXX Universal CapSense® Controller Development Kit Guide, Spec. # 001-57457 Rev. **
Copyrights
Copyrights
Copyright © 2010 Cypress Semiconductor Corporation. All rights reserved.
PSoC®and CapSense® are registered trademarks and CapSense Plus™ and PSoC Designer™ are trademarks of Cypress
Semiconductor Corporation (Cypress), along with Cypress®and Cypress Semiconductor™. All other trademarks or regis-
tered trademarks referenced herein are the property of their respective owners.
Purchase of I2C components from Cypress or one of its sublicensed Associated Companies conveys a license under the Phil-
ips I2C Patent Rights to use these components in an I2C system, provided that the system conforms to the I2C Specification
as defined by NXP.
The information in this document is subject to change without notice and should not be construed as a commitment by
Cypress. While reasonable precautions have been taken, Cypress assumes no responsibility for any errors that may appear
in this document. No part of this document may be copied, or reproduced for commercial use, in any form or by any means
without the prior written consent of Cypress. Made in the U.S.A.
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 PAR-
TICULAR 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 rea-
sonably be expected to result in significant injury to the user. The inclusion of Cypress’ product in a life-support systems appli-
cation implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges.
Flash Code Protection
Note the following details of the Flash code protection features on Cypress devices.
Cypress products meet the specifications contained in their particular Cypress Data Sheets. Cypress believes that its family of
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 that can breach the code protection features. Any of these methods, to our knowledge, would be dishonest and pos-
sibly illegal. Neither Cypress nor any other semiconductor manufacturer can guarantee the security of their code. Code pro-
tection 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.
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CY3280-28XXX Universal CapSense® Controller Development Kit Guide, Spec. # 001-57457 Rev. ** 3
Contents
1. Introduction 5
1.1 Kit Components ...........................................................................................................6
1.2 CD Directory Structure.................................................................................................6
1.3 Board Features............................................................................................................7
1.4 Documentation Conventions .......................................................................................7
1.5 Document Revision History ........................................................................................7
2. Quick Start 9
2.1 Getting Started.............................................................................................................9
2.1.1 Install PSoC Designer Development Software.................................................9
2.1.2 CapSense Best Practices ................................................................................9
2.2 Using the Board as Factory Programmed .................................................................11
2.2.1 Powering the Board........................................................................................11
2.2.2 Testing the Board...........................................................................................12
2.2.3 Resetting the Board to the Original Factory Programming ............................12
2.3 Creating a CapSense Project Using PSoC Designer 5.0 ..........................................13
2.3.1 Starting a New Project....................................................................................13
2.3.2 Adding CSD2X, LED, and EzI2Cs User Modules to Your Design..................13
2.3.3 Configuring LED and EzI2Cs User Modules..................................................14
2.3.4 Configuring the CSD2X User Module ............................................................15
2.3.5 Adding Code to main.c and Building the Project............................................16
2.3.6 Programming the CY3280-28XXX Board.......................................................17
2.3.7 Testing the Board...........................................................................................17
3. Hardware Design Notes 19
3.1 CY3280-28XXX Universal CapSense® Controller Board Features...........................19
3.1.1 PSoC Power Supplies....................................................................................19
3.1.2 Dual Channel CSD Scanning.........................................................................20
3.1.3 32.768 kHz External Crystal Oscillator...........................................................20
3.2 Hardware Interface and Description ..........................................................................21
3.2.1 Potentiometer in Parallel with Cmod Selection Jumper (JP1, JP2) ...............22
3.2.2 PSoC VCC Selection Jumper (JP3)...............................................................22
3.2.3 XRES/INT Selection Jumper (JP4)................................................................22
3.2.4 External 9V Battery Power Connector (BH1).................................................22
3.2.5 SPI/I2C Interface (J1).....................................................................................23
3.2.6 RS232 Interface (J2)......................................................................................23
3.2.7 ISSPI/I2CUSB Interface (J3)..........................................................................24
3.2.8 ICE Interface (J4)...........................................................................................24
3.2.9 External Power Supply Interface (J5).............................................................25
3.2.10 CY3280-SLM Board Connector (J6)..............................................................25
3.2.11 CY3280-CPM1 Board Connector (J7)............................................................27
3.3 Test Points.................................................................................................................28
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4 CY3280-28XXX Universal CapSense® Controller Development Kit Guide, Spec. # 001-57457 Rev. **
Contents
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CY3280-28XXX Universal CapSense® Controller Development Kit Guide, Spec. # 001-57457 Rev. ** 5
1. Introduction
Welcome to the CY3280-28XXX Universal CapSense®Controller Board. This kit is designed to
show the features of CY8C28XXX. The CY8C28XXX family of PSoC®1 devices includes the follow-
ing parts: CY8C28403-24PVXI, CY8C28413-24PVXI, CY8C28513-24AXI, CY8C28623-24LTXI,
CY8C28433-24PVXI, CY8C28533-24AXI, CY8C28243-24PVXI, CY8C28643-24LTXI, CY8C28445-
24PVXI, CY8C28545-24AXI, and CY8C28645-24LTXI. The CY3280-28XXX Universal CapSense
Controller Board contains the 56-pin OCD part. The 56-pin OCD part is only used for in-circuit
debugging.
Note OCD parts are NOT available for production.
The CapSense feature of CY8C28XXX can be implemented with the CY3280-SLM Universal
CapSense Linear Slider Module. The two boards are connected by a 44-pin connector. The other
features of CY3280-28XXX can be implemented with the CY3280-CPM1 Universal CapSense
Plus™ Controller Module. The two boards are connected by a 40-pin connector. The CY3280-SLM
Universal CapSense Linear Slider Module and the CY3280-CPM1 Universal CapSense Plus Con-
troller Module can be connected to the CY3280-28XXX Universal CapSense Controller Board at the
same time.
Figure 1-1. CY3280-28XXX Universal CapSense Controller Board
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Introduction
6 CY3280-28XXX Universal CapSense® Controller Development Kit Guide, Spec. # 001-57457 Rev. **
1.1 Kit Components
The following items are included in the kit:
■CY3280-28XXX Universal CapSense Controller Board
■CY3280-28XXX Universal CapSense Controller Board CD
■CY3240-I2CUSB Board
■CY3210-MiniProg1 Programmer
■PSoC Designer 5.0 SP6 CD
■Printed Documents
These tools are not included in CY3280-28XXX Universal CapSense Controller Board Kit, but may
be needed to use it. They can be found in other Cypress kits. These kits are available at
www.cypress.com. To demonstrate CapSense functions, the kit requires a CY3280-SLM to work. To
demonstrate CapSense Plus functions, the kit requires a CY3280-CPM1
■CY3280-SLM Universal CapSense Linear Slider Module Board
■CY3280-CPM1 CapSense Plus Module for CY8C28XXX
■CY3215-ICE
■CY3250-28XXX POD
1.2 CD Directory Structure
This list describes the higher level directory structures in the CD-ROM and does not explore the
lower level directories.
|---Docs 'Docs' contains the kit documentation in PDF form
|
|---Hardware 'Hardware ' contains the design files used in the
development of the Kit
| |---Schematic
| |---BOM
| |---SilkScreen
| |---Gerber
|
|---Firmware 'Firmware' contains the firmware related files
| |-- CapSense Example Project
| |-- CapSense Plus Example Projects
|
|---Software Software' contains PC software tools
| |---PSoC Tools
| |---I2CUSB Command
|
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CY3280-28XXX Universal CapSense® Controller Development Kit Guide, Spec. # 001-57457 Rev. ** 7
Introduction
1.3 Board Features
■Supports CY3280-SLM Universal CapSense Linear Slider Module
■Supports CY3280-CPM1 CapSense Plus Module
■External 12V power supply or 9V battery input
■Fixed 5V or adjustable voltage for PSoC
■ICE interface for in-circuit debugging
■MiniProg programmer interface
■RS232 interface
■LEDs indicate power status
■32.768 kHz external OSC option
■Multiple test points
1.4 Documentation Conventions
1.5 Document Revision History
Table 1-1. Document Conventions for Guides
Convention Usage
Courier New Displays file locations, user entered text, and source code:
C:\ ...cd\icc\
Italics Displays file names and reference documentation:
Read about the sourcefile.hex file in the PSoC Designer User Guide.
[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.
Table 1-2. Revision History
Revision PDF
Creation
Date
Origin of
Change Description of Change
** 01/18/10 JPLU Initial Release
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Introduction
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CY3280-28XXX Universal CapSense® Controller Development Kit Guide, Spec. # 001-57457 Rev. ** 9
2. Quick Start
In this chapter you will learn to get started with the CY3280-28XXX Universal CapSense®Controller
Development Kit, use the board as programmed by the factory, and create a CapSense project using
PSoC®Designer™.
2.1 Getting Started
This section contains instructions for installing PSoC Designer software and a discussion of
CapSense best practices.
2.1.1 Install PSoC Designer Development Software
1. Insert the PSoC Designer Development Software 5.0 Installation CD.
2. Install PSoC Designer Development Software 5.0.
3. Install .NET Framework 2.0.
4. Install PSoC Programmer.
5. A C Compiler license is required to build PSoC Designer C Language projects.
2.1.2 CapSense Best Practices
The Universal CapSense Controller was created using the best practices for CapSense layout. To
enable universality and development of the kit and its projects, certain design elements have been
changed from what is recommended for final products. Table 2-1 is a list of the design features in the
Universal CapSense Controller and what to change for final products.
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Table 2-1. Design Features in Universal CapSense Controller
Design Features Reason for Feature Impact Recommended Change
Sensing traces are routed
through a connector to
sensors.
Buttons, sliders, and
LEDs are placed on the
module board for greater
flexibility with custom
modules for development
and subsequent releases.
Connectors increase the
parasitic capacitance of
the sensors, effectively
reducing their sensitivity.
Connectors also create
another path for noise to
enter the system.
Sensors and control cir-
cuitry should be located
on the same printed circuit
board. Lower parasitic
capacitance by reducing
trace lengths.
Sensing traces are routed
to other schematic ele-
ments.
Universalityoftheboardis
enabled by population/
depopulation of 0Ωresis-
tors
Solder pads of 0Ωresis-
tors increase parasitic
capacitance.
Route traces directly to
sensing elements. Use as
few 0Ωresistors as possi-
ble.
Sensing traces are
located on the top layer.
Using vias to route traces
to bottom of board and
back to connector
increases parasitic capac-
itance.
Possible noise sensitivity
to stimulus on top side of
board. Finger presses on
routing of control board
can lead to sensor activa-
tion.
Route sensing traces on
non-user side of printed
circuit board. Route sens-
ing traces as far from
noise sources as possible.
Several regulators are
used, including a variable
regulator.
To demonstrate
CapSense at several volt-
ages.
Global and User Module
parameters may need to
be verified with changing
power supply.
Supply one regulated volt-
age to PSoC.
Test point on CMOD. Accessibility of charge/
discharge waveforms
A test point increases
noise sensitivity by acting
as an antenna.
Solder-pad test points for
leads offer better noise
immunity if test points are
required.
dGND spacing is general-
ized for noise immunity
and sensitivity.
Universality of kit required
middle-ground on many
parameters.
Designisnotoptimizedfor
high noise or very thick
overlays
Increase spacing for
thickeroverlaysand better
sensitivity. Decrease
spacing for greater noise
immunity.
Connection to shield elec-
trode is through a jumper
(module -J2)
Flexibility of module
boards for both CSD and
CSA control boards.
Higher resistance paths
can impair performance of
shield electrode in CSD
projects.
Dedicated trace for shield
electrode. Remove jump-
ers wherever possible.
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Quick Start
2.2 Using the Board as Factory Programmed
The CY3280-28XXX board is preprogrammed with demonstration firmware. When powered by a
PSoC MiniProg, a CY3240-I2USB Bridge, or an optional external power supply, the LEDs light up
when a finger touches one of the buttons.
These instructions assume that your board has not been reprogrammed from the factory settings. If
it has, and you would like to follow along with this demonstration, follow the instructions in section
2.2.3 Resetting the Board to the Original Factory Programming on page 12. Start this example with
2.2.1 Powering the Board.
2.2.1 Powering the Board
1. Connect CY3280-SLM Universal CapSense Linear Slider Module Board.
ESD protection circuitry is
not included.
Development/evaluation
platform without consis-
tent overlay is inherently
vulnerable to ESD events
Direct or air-separated
ESD testing may impair
operation or damage cir-
cuitry. ±2 kV limit on PSoC
pins (see data sheet).
Include an overlay and
ESD protection circuitry.
User Module Parameters
set to supplied overlay
thicknesses.
Projects optimized for
supplied hardware.
Sensitivity may not be
high enough for very thick
overlays.
Thicker overlays may
require verification of
parameters to ensure
proper operation.
Unused pins are not
routed directly to GND.
Pins brought out to con-
nector for subsequent
modules or custom
designs.
Possible noise path. Tie unused sensing traces
directly to ground.
0Ωresistors populated
throughout.
Universality of the board
enabled by population/
depopulation of 0Ωresis-
tors
Solder pads of 0Ωresis-
tors increase parasitic
capacitance.
Route traces directly to
sensing elements. Use as
few 0Ωresistors as possi-
ble
Table 2-1. Design Features in Universal CapSense Controller (continued)
Design Features Reason for Feature Impact Recommended Change
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12 CY3280-28XXX Universal CapSense® Controller Development Kit Guide, Spec. # 001-57457 Rev. **
2. Place shunts on pin2 and 3 of JP3 (Default Setting).
3. Connect your computer to the CapSense test board ISSP Connector (J3) using the PSoC
MiniProg and a USB cable. If this is your first time using the MiniProg, you will need to install the
driver using these steps before proceeding:
a. When the Found New Hardware Wizard opens, select Install the software automatically
(Recommended) option and click Next.
b. A warning message may tell you that the software you are trying to install has not passed Win-
dows Logo testing. Click Continue Anyway each time it appears.
c. When the installation is complete, click Finish.
4. Open PSoC Programmer by going to the Windows Start menu and selecting All Programs >
Cypress > PSoC Programming 3.10 > PSoC Programmer.
5. From the Port menu, select MiniProg1/<Identification Code>
6. Click Toggle Device Power. The D1 and D2 LEDs on the CY3280-28XXX board light red.
2.2.2 Testing the Board
Touch one or more buttons with your finger. The LEDs light up corresponding to the buttons being
pressed.
Figure 2-1. CapSense Buttons
2.2.3 Resetting the Board to the Original Factory Programming
Follow these steps to reset the board to the original factory installed programming:
1. Place shunts on pins 2 and 3 of JP1 and pins 1 and 2 of JP4. (Default Setting)
2. To reset the board to the factory conditions, connect your computer to the CY3280-28XXX board
ISSP Connector (J3) using the PSoC MiniProg and a USB cable.
3. Open PSoC Programmer by going to the Windows Start menu All Programs > Cypress > PSoC
Programming 3.10 > PSoC Programmer.
4. Click File Load, navigate to, and open the CY3280_28XXX_slm.hex file on the CD at:
..\Firmware\Capsense Example Project\CY3280_28XXX_SLM\
5. From the Device Family menu, select CY8C28XXX.
6. From the Device menu, select CY8C28645-24LTXI.
7. Click Program. "Programming Succeeded..." appears in the Actions pane when programming is
complete.
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Quick Start
2.3 Creating a CapSense Project Using PSoC Designer 5.0
This section walks you through the steps of creating a PSoC Designer project from scratch. At the
end of the project, you will be able to touch a button on the board and see the corresponding LED
light up.
2.3.1 Starting a New Project
1. Open PSoC Designer 5.0.
2. Select File > New Project.
3. Name the project MyProject.
4. If needed, click Browse to save the project in a different location.
5. Click OK.
6. Click View button, and select CY8C28645-24LTXI and click Select button.
7. Select C language for 'Main' file generation. Click OK.
Figure 2-2. Select Project Type Window
2.3.2 Adding CSD2X, LED, and EzI2Cs User Modules to Your Design
1. In the User Module window, expand Cap Sensors folder. Double click CSD2X or right click
CSD2X and select Place.
2. Place CSD2X UM with default configuration.
3. Expand Misc Digital folder. Double click LED or right click LED and select Place.
4. Repeat until there are five LEDs in your design.
5. Expand Digital Comm. Double click EzI2Cs or right click EzI2Cs and select Place.
6. All seven selected user modules should show in the Workspace Explorer window.
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14 CY3280-28XXX Universal CapSense® Controller Development Kit Guide, Spec. # 001-57457 Rev. **
Figure 2-3. Workspace Explorer
2.3.3 Configuring LED and EzI2Cs User Modules
1. Select LED_1 user module in the Workspace Explorer window.
2. Set the port to Port_1, the pin to Port_1_2, and Drive to Active Low in the Properties - LED_1
window.
3. Select LED_2 user module in the Workspace Explorer window.
4. Set the port to Port_0, the pin to Port_0_3, and Drive to Active Low in the Properties - LED_2
window.
5. Select LED_3 user module in the Workspace Explorer window.
6. Set the port to Port_0, the pin to Port_0_1, and Drive to Active Low in the Properties - LED_3
window.
7. Select LED_4 user module in the Workspace Explorer window.
8. Set the port to Port_2, the pin to Port_2_7, and Drive to Active Low in the Properties - LED_4
window.
9. Select LED_5 user module in the Workspace Explorer window.
10.Set the port to Port_2, the pin to Port_2_5, and Drive to Active Low in the Properties - LED_5
window.
11. Select EzI2Cs_1 user module in the Workspace Explorer window.
12.Set the Slave Addr to 67, and Address_Type to Statics.
13.Set ROM_Registers to Disable.
14.Set Auto_Addr_Check to Enable.
15.Set the I2C Clock to 100K Standard.
16.Set the I2C Pin to P1[0]-P1[1].
User Module Port Pin Drive
LED_1 Port_1 Port_1_2 Active Low
LED_2 Port_0 Port_0_3 Active Low
LED_3 Port_0 Port_0_1 Active Low
LED_4 Port_2 Port_2_7 Active Low
LED_5 Port_2 Port_2_5 Active Low
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Quick Start
2.3.4 Configuring the CSD2X User Module
1. Right click the CSD2X_1 user module, and select CSDADC Wizard.
2. Set the Switches to 5.
3. Assign the Switches to Pin Number., as in the following table.
4. Click OK. The Wizard will close.
5. In the Properties Windows of CSD2X, set the values as shown in Figure 2-4.
Figure 2-4. CSD2X User Module Configuration
Switch
Number Pin Number
SW0 P2[3]
SW1 P2[1]
SW2 P3[3]
SW3 P1[3[
SW4 P3[1]
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Quick Start
2.3.5 Adding Code to main.c and Building the Project
1. In the Workspace Explorer window, double click main.c under MyProject > Source Files folder.
2. Select all text in main.c and delete it.
3. Add the following code:
#include <m8c.h> /* part specific constants and macros */
#include "PSoCAPI.h" /* PSoC API definitions for all User Modules */
WORD I2C_Buf[15]; /* buffer for EzI2C */
void main(void)
{
BYTE i;
EzI2Cs_1_SetRamBuffer(sizeof(I2C_Buf),sizeof(I2C_Buf),(BYTE *)I2C_Buf); /*
setup I2C buffer */
EzI2Cs_1_Start(); /* I2C start */
M8C_EnableGInt ; /* enable global interrupt */
CSD2X_1_Start(); /* CSD2X start */
CSD2X_1_InitializeBaselines(); /* initialize the baseline */
CSD2X_1_SetDefaultFingerThresholds(); /* set default finger threshold
*/
while(1)
{
CSD2X_1_ScanAllSensors(); /* scan all sensors */
CSD2X_1_UpdateAllBaselines(); /* update all baseline */
if( CSD2X_1_bIsSensorActive(0)) /* check the state of button0 */
LED_1_On(); /* turn on LED0 */
else
LED_1_Off(); /* turn off LED0 */
if( CSD2X_1_bIsSensorActive(1)) /* check the state of button1 */
LED_2_On(); /* turn on LED1 */
else
LED_2_Off(); /* turn off LED1 */
if( CSD2X_1_bIsSensorActive(2)) /* check the state of button2 */
LED_3_On(); /* turn on LED2 */
else
LED_3_Off(); /* turn off LED2 */
if( CSD2X_1_bIsSensorActive(3)) /* check the state of button3 */
LED_4_On(); /* turn on LED3 */
else
LED_4_Off(); /* turn off LED3 */
if( CSD2X_1_bIsSensorActive(4)) /* check the state of button4 */
LED_5_On(); /* turn on LED4 */
else
LED_5_Off(); /* turn off LED4 */
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Quick Start
M8C_DisableGInt; /* disable global interrupt */
for(i=0;i<15;i++)
I2C_Buf[i] = CSD2X_1_waSnsDiff[i]; /* set the buffer */
M8C_EnableGInt; /* enable global interrupt */
}
}
4. Select Build > Generate/Build 'MyProject' Project and verify the compile finishes with no errors.
2.3.6 Programming the CY3280-28XXX Board
1. Connect your computer to the CapSense test board ISSP Connector (J3) using the PSoC
MiniProg and a USB cable. If this is your first time using the MiniProg, you will need to install the
driver before proceeding. Follow the instructions in 2.2.1 Powering the Board on page 11.
2. In PSoC Designer, select Program > Program Part. The PSoC Programmer application opens
3. From the Port menu, select MiniProg1/<Identification Code>.
4. Click Program. "Programming Succeeded..." appears in the Actions pane when programming is
complete
2.3.7 Testing the Board
1. Click Toggle Device Power.
2. Touch one or more buttons with your finger. The associated LEDs light up corresponding to the
buttons being pressed.
3. When you are done, click Toggle Device Power, and close PSoC Programmer.
4. Return to PSoC Designer and select File > Save Project.
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CY3280-28XXX Universal CapSense® Controller Development Kit Guide, Spec. # 001-57457 Rev. ** 19
3. Hardware Design Notes
3.1 CY3280-28XXX Universal CapSense®Controller Board Features
The CY3280-28XXX Universal CapSense Controller Board is used to demonstrate the features of
the CY8C28XXX family of PSoC®devices. To demonstrate some features of the CY8C28XXX fam-
ily, a special circuit is needed.
3.1.1 PSoC Power Supplies
There are two kinds of power supplies for PSoC VCC, fixed 5V or variable Vadj. The JP3 is used to
select the power supply. If pin 2 is shorted to pin 3, the fixed 5V is selected for the PSoC VCC. If
pin 2 is shorted to pin 1, the variable Vadj is selected for the PSoC VCC.
Figure 3-1. Schematics
Vadj is the output of the regulator (LP3875ES-ADJ). According to the schematics, the output can be
calculated from the following formula.
RV1 varies from 0Ωto 10 kΩ, so the maximum voltage and minimum voltage of Vadj can be calcu-
lated individually.
Vadj 1.216 1 R58
R23 R57+RV1
||
------------------------------------------+
⎝⎠
⎛⎞
×=
Vadjmax 1.216 1 R58
R23 R57 RV1min
||
+
--------------------------------------------------+
⎝⎠
⎛⎞
×1.216 1 3.9k
1.5k
----------+
⎝⎠
⎛⎞
×4.38V===
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20 CY3280-28XXX Universal CapSense® Controller Development Kit Guide, Spec. # 001-57457 Rev. **
If you want more information about the LP3875ES-ADJ, refer to the part’s data sheet at http://
www.national.com/mpf/LP/LP3875-ADJ.html.
If the fixed 5V power supply is selected for the PSoC VCC, follow the steps below.
1. Unplug the external 12V power supply and 9V battery power.
2. Place shunts on pin 2 and pin 3 of JP3.
3. Plug in the external 12V power supply or 9V battery power.
If Vadj is selected for the PSoC power supply, follow the steps below.
1. Remove any shunts on JP3.
2. Plug in the external 12V power supply or 9V battery power.
3. Measure the voltage of pin 1 of JP3 with a multimeter, tuning the potentiometer RV1 until the
desired voltage is acquired.
4. Unplug the external 12V power supply and 9V battery power.
5. Place shunts on pin 1 and pin 2 of JP3.
6. Plug in the external 12V power supply or 9V battery power.
3.1.2 Dual Channel CSD Scanning
The most significant improvement of CY8C28XXX over previous parts is the Dual-Channel CSD
scanning feature. Demonstrating this new feature requires two external capacitors. According to the
CY8C28xxx PSoC Programmable System-on-Chip Technical Reference Manual, pin 5 and pin 7 of
port 0 are dedicated for the external capacitors’ connections. The capacitor Cmod assigned to pin 5
of port 0 is connected to the internal left analog bus. The capacitor Cmod assigned to pin7 of port 0
is connected to the internal right analog bus. You can also use a potentiometer in parallel to Cmod,
but this is optional. If the potentiometer RV2 is needed for the left channel, put shunts on J6. If the
potentiometer RV3 is needed for the right channel, put shunts on J7. By default, resistors of R55 and
R56 are not populated.
Figure 3-2. Schematics
3.1.3 32.768 kHz External Crystal Oscillator
The CY8C28XXX has multiple clock sources. These include the phase locked loop (PLL), internal
main oscillator (IMO), internal low speed oscillator (ILO), and 32.768 kHz external crystal oscillator
(ECO) for precision, programmable clocking. The clocks, together with programmable clock dividers
(as a System Resource), provide the flexibility to integrate almost any timing requirement into the
PSoC device.
Vadjmin 1.216 1 R58
R23 R57 RV1max
||
+
--------------------------------------------------+
⎝⎠
⎛⎞
×1.216 1 3.9k
1.5k5.1k10k
||
+
-----------------------------------------+
⎝⎠
⎛⎞
×2.19V===
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