NXP UM10370 User Manual
UM10370
User Manual for the PCF8883 Evaluation Kit OM11055
Rev. 02 — 2 December 2009 User manual
Document information
Info Content
Keywords Capacitive switch, sensor, proximity switch, PCF8883, OM11055,
PCF8883 evaluation board
Abstract The OM11055 is a PCF8883 evaluation board which can be used to
demonstrate and evaluate the PCF8883 capacitive proximity switch. The
PCB is designed to make it easy to adjust the switch’s sensitivity. The
board can be powered using a Mini USB cable or a 9V battery.
NXP Semiconductors
PCF8883 Evaluation Kit OM11055
Revision history
Rev Date Description
02 20091202 Fully updated version to reflect the change of the evaluation kit. Revision 1 was written for
the preliminary evaluation board which was marked “MA142_EVALBOARD.BRD”.
Revision 2 is valid for the new evaluation kit OM11055 (not marked as such on the board).
01 20090731 Initial release
UM10370
Contact information
For additional information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: salesaddresses@nxp.com
UM10370_2 © NXP B.V. 2009. All rights reserved.
User manual Rev. 02 — 2 December 2009 2 of 11
NXP Semiconductors
PCF8883 Evaluation Kit OM11055
UM10370
1. Introduction
This user manual describes the OM11055 evaluation kit. This board was developed in
order to provide a tool for application engineers and development engineers wishing to
try and evaluate the single channel PCF8883 capacitive proximity switch. A LED displays
the status of the switch; test points facilitate measurements of important signals.
The desired capacitive sensor area can vary in terms of material, form, size and
switching distance. Each particular switch configuration demands a suitable electrical
circuit for the input signal. This board allows to easily change the input circuit and the two
capacitors which define the sensitivity and reaction speed of the sensor in a typical
application. This offers the opportunity to rapidly evaluate many possible switching
configurations.
Features
• Simple demo nstratio n of the single channel PCF8883 capacitive proximity switch
• Jump er to select one of the three possible switch modes of the PCF8883
• Evaluate different se nsor sizes (four different sensor plates included on the board) or
• Two po wer supply options: via USB cable or a 9V battery
• Provisio ns for through-hole components allowing them to be easily changed
• Conte nts of the kit
• All documentation is available from the NXP website:
:
off board user defined sensors
:
− One PCF8883 evaluation board
− One 3 ft USB A-B Mini Cable
http://www.standardics.nxp.com/support/boards/pcf8883
2. Quick start
The OM11055 is an evaluation board for the single channel PCF8883 capacitive
proximity switch.
1. Apply power to the board by connecting the supplied mini USB cable to the PCF8883
board and the other end into a PC or a USB power adapter. Alternatively a 9V
battery can be used. The capacitive proximity sensor is now active.
2. With no jumpers on J9 (timed mode), touching the sense plate CP1 will turn on the
green output LED (LD1) for about two seconds.
Please read this manual completely for configuration options and modes.
UM10370_2 © NXP B.V. 2009. All rights reserved.
User manual Rev. 02 — 2 December 2009 3 of 11
NXP Semiconductors
UM10370
PCF8883 Evaluation Kit OM11055
3. Board description and layout
Below the top view of the board is shown.
Option to connect an
external sense plate
High impedance op-amp
Sensor output connections
PCF8883
Output LED, LD1
Setting of output time
Mini USB connector for power
Setting of switch mode
(Push-button, toggle or pulse)
Connection for 9V battery
Optional header to select sense plate
(defaults to CP1)
Four sense plates (selected by J6)
Fig 1. Top view of the PCF8883 evaluation board
The lower halve is dominated by four sensor areas of different size. The actual circuit is
on the upper halve of the board. Arrows indicate the parts of interest which are described
more in detail in subsequent sections.
3.1 Setting the PCF8883 operation modes
The OM11055 allows the user to set one of three output switching behaviour modes,
using jumper J9. Refer to
a) With no jumper on J9, the PCF8883 will operate in pulse mode. The output is
activated for a defined time at each capacitive event. This defined time is
determined by C5.
b) With the jumper across the “TOG” and “TIM” pins, the PCF8883 will operate in
toggle mode (touch on, touch off).
c) With the jumper across the “SW” and “TIM” pins, the PCF8883 will operate in
momentary switch mode (push-button). The output is active as long as the
capacitive event lasts.
UM10370_2 © NXP B.V. 2009. All rights reserved.
User manual Rev. 02 — 2 December 2009 4 of 11
Fig 2:
Loading...