TDC-GP2 acam messelectronic gmbh, TDC-GP2 Datasheet
TDC-GP2
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TDC-GP2 Summary of contents
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... 2007 TDC-GP2 1.1 System Overvi ew ...
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... Introduction 1.1 System Overview TDC-GP2 is the next generation of acam general- purpose TDCs. Higher resolution and smaller package size make it ideal for cost sensitive industrial applica- tions. With special functional blocks like a fire-pulse generator, stop-enable, temperature measurement, and clock control it is perfectly suited for ultrasonic flow-meter and heat-meter applications ...
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... Oscillator .................................................................................................................26 5.1.3 Calibrating a Ceramic High-speed Oscillator ...................................................................................26 5.1.4 How to use Clock Calibration ........................................................................................................27 5.2 Fire-pulse Generator...............................................................................................................................27 5.2.1 General Description.....................................................................................................................27 5.2.2 Configuration ..............................................................................................................................28 5.3 Temperature Measurement .....................................................................................................................29 5.4 SPI-interface .........................................................................................................................................30 OPCodes .............................................................................................................................................30 5.5 Fast Initialization....................................................................................................................................31 5.6 Noise Unit .............................................................................................................................................31 6. Applications 6.1 Ultrasonic Heatmeter.............................................................................................................................32 6.1.1 General Description.....................................................................................................................32 acam-messelectronic gmbh - Am Hasenbiel 27 - D-76297 Stutensee-Blankenloch - Germany - www.acam.de 3 TDC-GP2 1.2 Index ...
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... Configuration ..............................................................................................................................33 6.1.3 Measurement Flow......................................................................................................................34 6.1.4 Current consumption...................................................................................................................34 7 Bug Report 7.1 Quartz Oscillator Start Up time...............................................................................................................36 7.2 DIS_PHASENOISE ..................................................................................................................................36 Contact acam-messelectronic gmbh - Am Hasenbiel 27 - D-76297 Stutensee-Blankenloch - Germany - www.acam.de 4 TDC-GP2 36 37 ...
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... Structure of the datasheet This functional description is made of several main sections for easy implementation of the TDC-GP2. The main sections are: 2. Characteristics and Specification This section is for reference with all the important technical data in a brief. Pinning, operating conditions and timings are shown. Several tables give an overview about the read and write registers as well as a short de- scription of the various bits ...
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... ° tbd mA V =Min. Vio-0 tbd mA, V =Min ol io LVTTL Level Max. io LVTTL Level Min TDC-GP2 2.1 El ectri cal C h aracte ri sti °C 125 °C Typ Max Unit 1.8 3.6 V 1.8 5 -40 120 °C ...
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... V 35 Vio = Vcc = 2.5 V -40 °C 2. Vio=3.3 V, Vcc =3 25°C Condition Rated Value Min Vio = Vcc =3.3 V PT1000 150 nF Capacitance Min 2 2. TDC-GP2 2.2 Timings Rated Value Unit Typ Max t.b t.b.d - t.b.d - Rated Value Unit Typ Max ps 25 °C 85 °C 3 111 25 ° ...
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... Bit OP Code acam-messelectronic gmbh - Am Hasenbiel 27 - D-76297 Stutensee-Blankenloch - Germany - www.acam. TDC-GP2 2.2 Timings Max @ 1.8V 2 ...
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... Start_Cal_TDC STOP no pass pass t S-EN EN_Stop t Figure 3 Description Enable Setup Time Enable Hold Time t ph Reset (at pin RSTN) t rfs not Start/Stop accept acc. Figure 4 Description Reset pulse width fore hits are accepted 9 TDC-GP2 SH-EN Min (ns) Max (ns accept Min (ns) Max (ns 200 ns - ...
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... Buffer type Schmitt trigger Schmitt trigger Schmitt trigger 12 mA tristate Schmitt trigger Schmitt trigger TDC-GP2 2.3 Pin description 24 PT1 PT2 Vio GND PT3 PT4 LoadT 17 SenseT Value If not used GND GND LOW active LOW active LOW active n ...
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... Am Hasenbiel 27 - D-76297 Stutensee-Blankenloch - Germany - www.acam.de Schmitt trigger Schmitt trigger Schmitt trigger TDC-GP2 2.4 Package Drawings HIGH active Vio HIGH active Vio GND GND HIGH active Vio b ...
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... Power supply 2.5.1 Supply voltage Although the TDC-GP2 is a fully digital circuit, some analog measures affect the circuit. The reason is that the TDC is based on the internal analog measure 'propagation delay time' which is influenced by temperature and supply voltage. A good layout of the supply voltage is essential for good measurement results. It should be high capacitive and of low in- ductance ...
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... calibration use 32,768 kHz as cycle clock 1 = use 128 * CLKHS as period for cycle clock (32µs with 4 MHZ high speed clock signal ) 13 TDC-GP2 2.6 Regi ster setti ngs *def Reg4 *def Reg5 0 s. s.c. ...
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... Fast init mode disabled 1 = Fast init mode enabled 14 TDC-GP2 2.6 Regi ster setti ngs ...
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... Bit 23 = Timeout interrupt enable Bit 22 = End Hits interrupt enable Bit 21 = ALU interrupt enable DELVAL1 = 0 to 16383.96875 µ 256 µ 1024 µ 4096 µ MHz ClkHS 15 TDC-GP2 2.6 Regi ster setti ngs MRange2 Start MRange2 Stop Ch1 Stop Ch1 Stop Ch1 ...
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... Bit negate output Fire2 Bit disable output Fire2 Bit disable output Fire Error Error Timeout short open Precounter 16 TDC-GP2 2.6 Regi ster setti ngs Timeout # of hits # of hits TDC Ch2 Ch1 - Pointer result register ...
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... X c. Measurement range 2 In measurement range 2 the TDC-GP2 only supports calibrated measurement. The results are given in multiples of the internal reference clock (= external reference clock divided (DIV_CLKHS)). Calibrated data are 32 bit fixed point numbers with 16 integer bits and 16 fractional bits. Any calibrated result covers therefore 1 result register ...
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... Each input separately can be set to be sensitive to rising or falling edge or both edges. This is done in register 0, Bits (NEG_START, NEG_STOP1, NEG_STOP2) and register 2, Bit 19&20, RFEDGEx. Furthermore all Start/Stop-inputs support a high active enable pin. 1.8 µs 18 TDC-GP2 3.1 General Descri pti ...
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... Set the number of expected hits In register 1, Bits and 11 to 13, HITIN1 and HITIN2 the user has to define the number of hits the TDC-GP2 has to wait for. A maximum each acam-messelectronic gmbh - Am Hasenbiel 27 - D-76297 Stutensee-Blankenloch - Germany - www.acam.de channel is possible. The TDC-GP2 measures until the set number of hits is registered or a timeout occurs ...
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... There are further configuration options that will be described later in this chapter. After the configuration the user has to initialize the TDC-GP2 by sending opcode "Init" so that the TDC accepts Start and Stop hits. 3.2.2 Measurement After an initialization the TDC unit will start with the first pulse on the Start input ...
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... Now all Hit data are available from registers The load pointer value the end the TDC-GP2 has to be initialized again to be ready for the next measurement. This is done by send- ing the opcode "Init" so that the TDC accepts new Start and Stop hits ...
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... Further all Start/Stop-inputs support a high active enable pin. Note: In case the Start-Stop interval is less than the lower limit t the TDC will ignore more and more events the zz smaller it is case there will be wrong results. 22 TDC-GP2 ...
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... Set the number of expected hits In register 0, Bits 8 to 10, HITIN1 the user has to define the number of hits the TDC-GP2 has to wait for. A maximum channel 1 is possible. The number HITIN1 always has to be higher by 1 than the number of expected hits ...
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... There are further configuration options that will be described later in this chapter. After the configuration the user has to initialize the TDC-GP2 by sending opcode "Init" so that the TDC accepts Start and Stop hits. 4.1.2 Measurement After an initialization the TDC unit will start with the first pulse on the Start input ...
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... Now all hit data are available from registers The load pointer value the end the TDC-GP2 has to be initialized again to be ready for the next measurement. This is done by sending the opcode "Init" so that the TDC accepts new Start and Stop hits. ...
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... Details and Special Functions 5.1 Oscillator The TDC-GP2 uses clock signals depending on the operating mode: High-speed clock for calibration and as a predivider for the TDC measuring unit in measurement range 2 32 kHz clock signal used for internal timer functions. 5.1.1 High-Speed Oscillator Generally the TDC-GP2 needs MHz high-speed clock for calibration ...
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... TDC-GP2 allows to execute a calibration measurement that allows to compensate this behavior. This measurement is based on the very precise 32.768 kHz clock. The TDC-GP2 generates start/stop pulses from the 32.768 kHz and measures this time interval with its TDC unit. The result is stored in the result reg- ister and the interrupt flag is set ...
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... The fire- pulse generator allows to generate and send pulse sequences multiple times for use in a quasi “sing- around” method. Using this feature the received pulse sequence is fed into TDC-GP2 Fire_In input digitally amplified and directly forwarded to the output buffer for an immediate re-emittance without any clock delay. ...
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... Figure 18 The temperature sensor should have a minimum resis- tance of 500 Ohm. The TDC-GP2 measures the dis- acam-messelectronic gmbh - Am Hasenbiel 27 - D-76297 Stutensee-Blankenloch - Germany - www.acam.de charge times of the RC-networks made of each resistor and the capacitor. The precision of the temperature measurement is about 0.004° ...
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... Short circuit: equivalent to a very short time interval (< Tref = 2 µ MHz). The TDC-GP2 writes a 0x0 to the output register of the shorted sensor. 2. Broken sensor: equivalent to no stop signal or timeout. The TDC-GP2 writes a 0xFFFFFFFF into the output register of the open sensor ...
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... SO output. Each positive edge transfers the next lower Bit to the output. 5.5 Fast Initialization In measurement range 1 the TDC-GP2 offers the possibility of a fast initialization. Activated by setting register 1, Bit 15, EN_FAST_INIT = "1" the interrupt flag automatically initializes the TDC. So the TDC is already prepared for the next measurement while the data can be read out ...
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... The measurement is fairly automated by the TDC-GP2. The microprocessor just sends a start command. The TDC then fires the transducers and measures the time of flight. It calibrates the results and provides them to the microprocessor ...
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... Start off DELVAL1 TDC-GP2 6.1 Ul trasoni c He atm Register 3 0x083300 x h Description Value 1 s.c. 1 s.c. E ALU 1 EN_ERR_VAL off 0 SEL_TIMO_MB2 1024µ ...
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... The average current then is about 0.085 µA. This is about 50 times less than with solutions without a TDC. c. Quiescent current Thanks to the current optimized 0.35µ technology the quiescent current is less than 150 nA typ. 34 TDC-GP2 6.1 Ul trasoni c He atm RES_0/RES_1 ref /R = RES_3/RES_2 ref are provided by the µ ...
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... It is possible to operate the system from a lithium- thionylchloride AA cell for 10 years without changing the battery years runtime it maybe even possible to work with a low-cost 3V CR2450 coin cell battery. acam-messelectronic gmbh - Am Hasenbiel 27 - D-76297 Stutensee-Blankenloch - Germany - www.acam.de 6.1 Ul trasoni c He atm TDC-GP2 ...
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... Ceramic Resonator With a ceramic resonator the oscillation start up time is about 200 µs. There is no problem with TDC-GP2's internal delays. We recommend the use of ceramic resonators in all applications targeting ratio measurements (like ultrasonic flow metering). ...
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... Kyungwon building, 416-6 Jakjeon-dong GYEYANG-GU, INCHEON 407-060 Neunbrunnenstr. 55 8050 Zürich 264 Center Street Miamiville, Ohio 45147 100, Prospekt Mira, Moscow, 129626, Russia 37 TDC-GP2 7.2 DIS_ PHASENOISE Tel: +49-7244-7419-0 Fax: +49-7244-7419-29 email: support@acam.de www.acam.de Té Fax : + commercial@microel.fr www.microel.fr Tel ...