E297S USER'S GUIDE. Overview. Fast Start. Quantum Research Group Ltd.

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1 Overview Fast Start The E97s board is designed for rapid development and programming of the QTM000 module for capacitancebased sensing systems. It includes all the circuitry required to make a fully functiing sensor system and to allow programming of the QTM000. This board has a full-duplex serial interface that allows cnecti to a PC for functi ctrol and data viewing. This board is fully compatible with QTWinview software. The QTM000 module uses the QT970B IC as its basis; a datasheet for this part is available from Quantum s web site. USER'S GUIDE To begin using the board right away:. Insert a QTM000 module into the ZIF socket, being certain to align the module so that the pin notch in the module faces the ZIF lever arm.. Cnect a switchable source of + to +0VDC to the screw terminal block. This may be a 9V alkaline battery or a bench supply. D't turn the power just yet. 3. Cnect the RS3 serial cnector to a PC using a 'straight-through' extender type DB9 serial cable. 4. Plug in the thin coax cable to the cnector labeled 'SIGNAL' the board; cnect the center cductor of the other end of this cable to a piece of metal foil or other floating metal object.. Run QTWinview the PC. Click FILE LOAD GRID and open the file 'QT970B.qdf'. 6. Click COMM SETUP and make sure the PC serial port matches the e you are using. Make sure the Baud Rate is set at Apply power to the board. One or both LEDs will illuminate or flash.. Click 'GO ONLINE' at the bottom of the QTWinView window. 9. Click 'GRAB CURRENT' at the bottom of the QTWinView window. Cells in the Setup table will highlight to reflect the settings loaded in the QTM Click 'POLL QPRO' at the bottom of the QTWinView window to view the actual signals coming from the board.. Push the BG butt the to calibrate the QTM000 and bring the signal into view the screen. If the board will not communicate with the PC, check the Baud rate and Comm port settings, your cable cnectis, and the power to the E97s. If the board will still not communicate, see the Trouble Shooting secti of this document. As your hand approaches the electrode, the Signal level will rise to reflect the increase in capacitance. Quantum Research Group Ltd. techsupport@qprox.com US: + (4) UK: +44 (0) QProx is a trademark of QRG Ltd. R.0 030

2 Board Details Power Cnector This screw terminal strip can be used to power the board. The voltage should be between + and +0 volts DC. Power should be free from switching noise and short-term fluctuatis for best performance. Sense Cnector This -pin polarized header provides the interface to the sensing electrode. One pin is board ground and should be cnected to the shield of the cable (if shielded). The other is the signal line which should be directly cnected to the sense electrode. RS3 Cnector This cnector provides bi-directial communicatis between the E97s and an external host, like a PC. It allows full ctrol over the device including calibrati and Setups. It also allows for real-time downloading of signal and reference informati. QTWinview software makes use of this cnector. Gain Jumper This -positi jumper ctrols the gain of the opamp circuit. The 'Hi' positi has 6x higher gain than the 'Lo' positi. Refer to the schematic diagram and the QT970B datasheet for further details. Sampled Analog Output This -pin header cnector labeled 'ANA OUT provides the sampled analog output signal from the QTM000 module. This signal can be fed into an ADC for further processing. Note that lg wire lengths this cnecti can cause the opamp of the QTM000 to break into high frequency oscillati, and sometimes ly at certain output voltage levels. If this happens, add additial series-r inline with ANA to the wiring from this cnecti. Cle Cnectors There are two cle cnectors: Cle in and cle out. These are for use with the QTM00CA cling adaptor which can take setting from the QTM000 module and copy them into additial modules or, copy in from another, E97S, or ESR board. The cling mechanism provides for stand-ale duplicati of Setup parameters stored in the eeprom (but not calibrati data). The cle out cnector is compatible with the QTM00CA s cling cable, while the cle-in port is compatible with the QTM00CA s pogo pins. Inbound cling is accomplished during power up; when the power to the QTM000 comes up it checks for the presence of a cling adaptor and if present, absorbs the informati from it. Inbound cling can also take place after the OBJ butt is momentarily pressed while the cling source is present. Outbound cling from the can take place ly when the OBJ butts is held down while powered. SPI Port This output-ly port allows transfers of data, such as signal levels and module status, to -board peripherals which can take clocked data. Possible targets include shift registers and SPI peripherals like DACs. The signals available are the same as those available the Analog port cnector, but in clocked-digital form. Refer to the QT970B datasheet for data format and clocking details. The pinout of this cnector is shown in the schematic. BG Butt This butt ctrols the recalibrati of the Background level of the sensor. It is the primary ctrol for setting the reference point and recalibrating the device. Pushing this butt will normally act to recenter the signal and its reference level at the desired reference set according to Setup, Reference Offset, in the Setups table in this guide. A great deal more is written about the BG and OBJ functis in Secti 3 of the QT970B datasheet.

3 Board Details OBJ Butt This butt ctrols the 'Object Learn' point of the sensor. It sets the trip point at which an object will be detected when the device is in the BG/OBJ or OBJ modes (see QT970B datasheet for details). If this butt is not pushed, the detecti point is set to a level determined by Setups 0, Threshold. RT/CT Transfer Timing Optis The RT and CT sockets (located mid-board) can be used to narrow the QT sampling time for systems where cductive films (like water) are a problem. RT and CT allow enhanced water suppressi by restricting the amount of time stored charge in the water film has to return to the sampling capacitor. The 'normal' transfer time (that with RT/CT unused) mirrors the charge time, and can extend down to 00ns (See Setups Table in QTWinView or the QT970B datasheet). These 'normal' times are accessed by removing RT and placing a jumper in the socket pins for CT (factory default). By inserting a 470 to 4.7K resistor at RT and inserting a 0pF to 00pF capacitor for CT, a variety of transfer times can be obtained. These transfer times must be adjusted with the aid of an oscilloscope test pin FR (located near the -pin Signal cnector). Transfer times well below 0ns are possible with this circuit. STAT LED This LED acts as a multipurpose indicator that shows output state, error cditis, and input feedback. STAT will output as follows depending sensor state: Running and not detecting: LED flickers at a 0% duty cycle. Running and detecting: LED flickers at a 90% duty cycle (bright flicker). When either BG or OBJ are pushed: LED is forced for the durati of the push. If BG or OBJ are pushed for >secs: (Change of cal mode requested) After butt release, the LED will go 'solid ' (no flicker) for ¾ secd before it enters the new calibrati mode. While calibrating: LED will be ; this usually takes under a secd. If a Sense line short-circuit is detected while running: LED will go 'solid ' for the durati of the short. On a calibrati error: LED will output a repeating error code, provided that Output Error Code functi [E.a] is set : Single repeating pulse: CHG shorted to ground Double repeating pulse: Excess capacitive load Triple repeating pulse: Unstable signal, cannot calibrate The device will repeatedly try to calibrate between each set of flashing signals. If [E.a] is, the recalibrati attempts will be much quicker, since the STAT codes are not output to the LED. OUT LED This LED reflects the state of the OUT line. If 'On', the OUT line is high. Note that the OUT line can be inverted in polarity using Setup 'J'. If set to 'Active Low', the LED will be if a detecti is sensed. The OUT signal can be stretched by cfiguring Setup 'L'.

4 Fresh Defaults The E97s' factory defaults are shown in the accompanying Setups Table. These defaults are for a forgiving operati mode that requires ly the press of the BG butt for recalibrati, and for a simple, low Baud rate cnecti to a PC. Factory defaults can be restored to those shown by the following procedure:. Unpower the board. Hold down both the BG and OBJ butts together 3. While holding the butts down, apply power and ctinue to hold the butts for 3 more secds. 4. Release the two butts. The board will now be in the factory default state, and will communicate at 9600 Baud with a host PC. General Hints Use QTWinView to observe signals and set up the sensor -! Double-click items in the 'grid' to quickly alter the Setups the board.! Be sure to load in the Grid for the 'QT970B' device before double-clicking matrix cells.! Change Setups by simply double-clicking cells. Use the 'Save Grid' feature to save your own settings to a setup file disk, and to even create a new butt the top butt bar.! Observe the relatiship between the signal, the reference level, and the threshold points. This is the key to understanding the behavior of the sensor during detecti, drift compensati, and calibrati.! D't be afraid to change Setups to wild combinatis. You can't break it.! If you make a mistake that causes the board to stop communicating with the PC, use the 'Fresh Defaults' method above to restore the board s default settings. Use rubber feet under the board, or mount it something -! Mechanical stability is important even the board itself. A loose board can cause small signal variatis that you might find hard to explain.! Keep the electrode stable for the same reass. Refer to the QT970B datasheet -! The datasheet has loads of informati that will help you understand the product, including circuit operati details. Only an extract of that informati appears here.

5 Trouble- Shooting Will not communicate with the PC! Bad serial cnectis " Check/replace serial cable! Bad or cflicting Comm port PC " Shut down other tasks that may also be using the same comm port, IRQ or I/O Address the PC. " Use a different PC.! Baud rate setting changed inadvertently " Restore factory defaults into QTM000 (see 'Fresh Defaults' secti)! Dead battery or power supply out of usable range " Restore power to within correct range LEDs not working as expected! Wrg Setups mode " Check or restore Setups, and / or, " Hold down BG for 3 secds! Eeprom wrg type or eeprom not inserted! Shorted sense line " Restore power to within correct range Board will not calibrate! Excess capacitive load " Reduce burst length, or, " Reduce Cx loading! Shorted sense line! Low power supply voltage! Unstable capacitance load due to electrode or wiring Noisy signal! Noise power supply " Add supply filtering capacitors " Use a local supply regulator! Electrode too close to power wiring! Noisy load cnected OUT line! Ground loop interference! RFI from a transmitter or adjacent digital product " Add some series-r to the electrode lead " Shield the board in a metal box! Insufficient signal filtering " Increase amount of median and/or boxcar filtering

6 QTM000 Setups Bold Boxes Denote Factory Default settings SELECT DESCRIPTION 0 3 SETTING A B C D E F G H J L N P U D.a D.b D.c D.d E.a E.b F.a F.b Detect Threshold, counts Hysteresis, % of Threshold Reference Offset (hex / decimal) unused Pulse Width - ns Burst Length, pulses Burst Spacing Randomize Bursts, % Drift Rate, secds/bit Median Filter, length Boxcar Average, length Detect Integrator, counts Max On-Durati, secds Detecti Mode Output positive signals Output negative signals Max On-Durati engages crossing Drift compensati during detect Calibrati ctrol output error code if cal error recal if ref drifts into boundary Drift Store / Data Locking / Moti Drift store interval, minutes between saves Data locking Serial Modes / UART Rate Verbose Data Polarities OUT pin: Active = FR pin: Drive = Output Stretch, secds unused SPI Format Mode / SPI Data Output 6 0 0x0 / µs infinite + * * Off synth High High 0 bits Mode_ 40 0x0 / µs.% P synth-ref Low High 0. 6 bits Raw 0 0x60 / ms 0% P set Low Low 0. +Synth 3. 0x40 / ms % P ref High Low 0. Synth 9 0x70 /,000 3 ms P canceltn -Synth 4 0x0 /, ms V DI Synth 0xA0 / 60, ms VS from U 3 Ref 0xC0 / 9 6 0ms V status DI 6 0xE0 / ms V err code 7 Status 4 0xF0 / moti V 0

7 Schematic

8 Quantum Research Group Ltd. Capstan House, High Street Hamble, Hants SO3 4HA United Kingdom US: + (4) UK: +44 (0) fax: +44 (0) QProx is a trademark of QRG Ltd.