™ DAC488HR ® 16-bit D/A Converter with Digital I/O & IEEE 488 the smart approach to instrumentation™ Features • • • • • • • • • • • • Two or four isolated 16-bit outputs 100-kHz/channel update rate 480 Ksamples/channel max buffer ±1, ±2, ±5, & ±10 VFS programmable unipolar & bi-polar output ranges One-shot, step, burst, waveform, & continuous output modes GET, external TTL, IEEE command, & time event trigger sources ASCII, binary, integer decimal, & hexadecimal data formats Standard sine, square, & triangle waveform generation 500 VDC channel-to-channel isolation Eight digital inputs & eight digital outputs 100 mA high-current outputs LabVIEW® drivers The versatile DAC488HR functions as a voltage source, function generator, and an arbitrary waveform generator Up to 13 IEEE 488 devices SCSI488/S IEEE 488 Data Acquisition Instruments DAC488HR/2 The DAC488HR™ is an IEEE 488 programmable 16-bit D/A converter. It can be configured with either two or four output channels, which are optically isolated from each other and from IEEE 488 common by up to 500 VDC. Each channel is independently programmable for 1, 2, 5, or 10 VFS unipolar or bipolar output, specified as either bits or volts in ASCII, integer, hexadecimal, or binary format. Multiple output modes, multiple clock and trigger sources, and buffer management enable the DAC488HR to function as a precision voltage source, a function generator, or an arbitrary waveform generator. Waveforms captured by IOtech’s 16-bit, 100-kHz ADC488A series (see p. 243) digitizers can be edited and transferred to the DAC488HR for output. The ADC488A™ series and DAC488HR in combination form a powerful waveform I/O system. Typical applications include transducer simulation, disk drive testing, vibration analysis, and materials testing. Filter488 DAC488HR IEEE IEEE 488 controller Trigger Modes The DAC488HR’s five trigger modes support a wide variety of applications. Bus Control Mode. Each port is programmed to output a specified value under direct control from the IEEE 488 bus. This mode is useful for maintaining an initial value until a specified condition occurs. Step Mode. When a specified trigger is detected, a value is output from the buffer, and the DAC488HR is automatically re-armed until the specified buffer count is reached. The last specified buffer value is held as the output. Q U I C K tel: 440-439-4091 fax: 440-439-4093 248 DAC488HR +- +- +- +CH1 CH2 CH3 CH4 2- or 4-channel 16-bit, isolated 100-kHz analog outputs 8 digital 8 digital outputs inputs Burst Mode. Functionally identical to step mode, except that waveforms rather than single values are output. Waveform Mode. Based on recognition of a trigger, the waveform buffer is output for a specified number of cycles. Continuous Mode. Data is continuously input from the IEEE 488 bus and output to an analog channel at rates up to 200 Kbytes/s upon the detection of a specified trigger. This mode is ideally suited for audio, speech, and other applications that require long duration waveforms. F I N D [email protected] www.iotech.com ™ DAC488HR ® General Information the smart approach to instrumentation™ DAC488HR Design Four independent analog output modules are optically isolated from the IEEE 488 bus, digital circuitry, earth ground, and chassis common by up to 500 VDC. Each module consists of a microcontroller and expandable data buffer. A common update clock is shared by all ports, ensuring synchronization. Four internal clock sources are available to meet a wide variety of applications including CD and DAT testing. An external clock source (up to 10 MHz) allows synchronization to an external frequency reference and can be used to synchronize the DAC488HR to the ADC488A series (see p. 243) digitizers for stimulus/response applications. Isolated Nonisolated Power source 1 Isolated analog output D/A channel 1 Power source 2 D/A channel 2 Multiple Trigger Sources Power source 3 All DAC488HR ports share a common trigger source, ensuring multi-channel synchronization for applications with critical time and phase relationships. Trigger sources for the DAC488HR include trigger command, IEEE 488 Group Execute Trigger (GET), and external TTL (rising or falling edge) signal input. Triggers can also be initiated on periodic intervals from 2 ms to 65,535 ms, specified in 1 ms increments. The DAC488HR provides a delayed TTL-level trigger output for stimulus/response applications in which the device under test (DUT) must attain a steady state prior to measurement. This function allows users to specify a time delay, in update clock counts from 1 to 65,535, between the DAC488HR’s output and the trigger signal’s output. D/A channel 3 Power source 4 D/A channel 4 PS main Multiple Clock Sources The DAC488HR features four internal clock sources and accommodates an external clock source (up to 10 MHz) for updating the output ports. A 16-bit counter is used to provide update rates to meet application requirements. For example, the 200-kHz clock and the 5-MHz clock can be divided down to any rate between 3 Hz and 100 kHz for general purpose applications; the 5.6448-MHz clock can simulate 44.1-kHz audio CD signals; and the 6.144-MHz can simulate 48-kHz audio DAT signals. For synchronizing external circuitry to DAC488HR output, an update clock signal is also provided. Buffer Management The DAC488HR’s step, burst, waveform, and continuous trigger output modes can be used with flexible buffer management functions to output stepped voltages, any one of five standard waveforms, or user-defined arbitrary waveforms. Waveforms are loaded from the IEEE 488 bus into the DAC488HR’s resident 8 Ksample buffer at rates up to 500 Kbytes/s. To output standard predefined sine, square, and triangle waveforms, the user specifies the starting memory location, number of samples, max/min values, duty cycle, and the number of times the cycle is to be repeated or “looped.” The “looping” fax: 440-439-4093 Internal peripheral interface bus IEEE 488 interface Each DAC488HR output port features a separate microprocessor and buffer memory for independent waveform management function outputs specified buffer segments up to the full available buffered size for repetition up to 65,535 times. This conserves memory space by allowing long periodic waveforms to be defined in a single cycle. Additionally, for applications that exceed the DAC488HR’s internal buffer capacity, waveforms can be output continuously from an IEEE 488 controller at up to 200 Kbytes/s via the IEEE 488 bus. Nonvolatile Storage The DAC488HR uses resident nonvolatile random access memory (NVRAM) to store the calibration constants determined during digital calibration, and to store its power-up default configuration. Q U I C K tel: 440-439-4091 Main processor digital circuitry 249 F I N D [email protected] www.iotech.com IEEE 488 Data Acquisition Instruments Non-isolated digital I/O ™ DAC488HR ® General Information the smart approach to instrumentation™ Functional Requirement Waveform(s) Typical Application Continuously output a standard wave function under program control Standard function generator outputs for general purpose applications Output a series of voltage values based on TTL triggers Sequenced V out for controlling power supplies or other analog programmable instruments T1 T2 T3 T4 Analog output signal Initiate a trigger delay from 1 to 65,535 update clock pulses IEEE 488 Data Acquisition Instruments trigger event trigger delay Allows a device under test (DUT) to attain a steady state prior to measurement Synchronously output multiple waveforms under program control Ideal for stimulus/response applications with critical time and phase relationships Output a standard waveform acquired by the ADC488A series digitizer Ideal for simulating complex signals such as EKGs and contact bounce Continuously output a large arbitrary waveform from the IEEE 488 bus at up to 200 Kbytes/s For audio system testing, speech research, and other tests requiring long-time waveform generation Stimulus/Response System When configured with an ADC488A series A/D converter, the DAC488HR is wellsuited for stimulus/response testing. For synchronous operation in which acquisition must begin simultaneously with the stimulus output, the DAC488HR’s TTL trigger output is connected directly with the ADC488A’s TTL trigger input; for nonsynchronous operation in which acquisition must begin at a specified time after the stimulus output, the DAC488HR’s trigger output can be “delayed” up to 65,535 update clock counts. Multi-DAC488HR Synchronization Multiple DAC488HRs can be configured in master/slave mode to synchronously output data either from their internal buffers, or continuously from the IEEE 488 bus. When daisy-chained together using the CA-112 master-slave cable, the number of DAC488HRs in a system is limited only by the number of available IEEE 488 addresses, and the trigger “latency” between each unit is 60 ns*. For applications that require non-additive trigger latencies, the DAC488HRs can be configured in parallel, limiting total system trigger latency to 60 ns. Support Software The DAC488HR series is shipped with QuickBasic® and C sample programs. Free VIs (Virtual Instruments) are available from IOtech that enable the immediate integration of the DAC488HR series into existing LabVIEW® applications. Each of these ready-to-use VIs provide immediate access to common DAC488HR functions, and both include source code that can be modified to meet specific application requirements. * A system with one master and three slave units will have a total system trigger latency of 180 ns Q U I C K tel: 440-439-4091 fax: 440-439-4093 250 F I N D [email protected] www.iotech.com ™ DAC488HR ® Specifications & Ordering Information the smart approach to instrumentation™ Data Storage and Output Analog Output Number of Channels: 2 or 4 DC Output Voltage/Resolution 1V Range: ±1V, 30.5 µV/bit 2V Range: ±2V, 61 µV/bit 5V Range: ±5V, 152 µV/bit 10V Range: ±10V, 305 µV/bit DC Output Current: ±10 mA max Accuracy (25 ±5˚C) 1V Range: ±0.02% ±50 µV 2V Range: ±0.02% ±100 µV 5V Range: ±0.02% ±250 µV 10V Range: ±0.02% ±500 µV Polarity: Unipolar or bipolar (software selectable) Output Impedance: 10 Ohm Zero Offset: 50 to 500 µV Linearity: 0.005% Differential Linearity: 0.001% Update Rate: 100 Ksamples/s (max per channel); all signals from the data buffer are 100 Ksamples/s max; any single channel from the IEEE 488 bus to output is 100 Ksamples/s max; any two channels from the IEEE 488 bus to output are 50 Ksamples/s max; any two channels from the IEEE 488 bus to multiple DAC488HR’s are 20 Ksample/s Settling Time: 6 µs to 0.003% FSR Temperature Coefficient: (±0.002% ±100 µV)/˚C; 0˚ to 20˚C, 20˚ to 30˚C, and 30˚ to 50˚C Channel-to-Channel Isolation: 500V max Channel-to-Digital Common and Chassis Isolation: 500V max Connectors: DB9 (female) per channel; mating connector supplied Digital I/O Digital Inputs: 8 TTL level compatible, external TTL trigger, external TTL clock input Digital Outputs: 8 TTL level compatible, also configurable as open collector with 100 mA drive, and delayed trigger output signal, update clock output. Connectors: DB15 (female) per input and output port; mating connector supplied Data Buffer: 8 Ksamples standard (per channel); 128 Ksample option or 480 Ksample option (per channel) Data Format: ASCII, integer decimal, hexadecimal, and binary Output Modes: Direct, step, burst, waveform, and continuous Trigger Sources: GET, periodic time interval, external (TTL level), and command Trigger Latency: Daisy chain mode; 60 ns (additive per unit) Parallel mode; 60 ns (non-additive system maximum) General Power: 90 to 125 or 210 to 250 VAC, 50/60 Hz; 20 VA max Environment: 0˚ to 50˚C; 0 to 95% RH, non-condensing Controls: Power switch, external dip switch for IEEE address Dimensions: 425 mm W x 305 mm D x 45 mm H (16.75” x 12” x 1.75”) Weight: 3.6 kg (7.9 lbs) Supplied Accessories: Analog output connector, digital I/O port connector Ordering Information Description Isolated 2-channel converter with 8 Ksample memory per channel; includes analog output connector; digital I/O port connector; and rack-mount kit Isolated 4-channel converter with 8 Ksample memory per channel; includes analog output connector; digital I/O port connector; and rack-mount kit 128 Ksample memory expansion for one channel 480 Ksample memory expansion for one channel Shielded cable with male DB9 connector for analog output, 6 ft. Shielded cable with male DB15 connector for digital I/O, 6 ft. DAC488HR master/slave cable, 3 ft. Shielded IEEE 488 cable, 6 ft. LabVIEW® driver Part No. DAC488HR/2 DAC488HR/4 MEMX3* MEMX4* CA-89 CA-90 CA-112 CA-7-3 LBV/DAI Related Products Hardware ADC488/16A ADC488/8SA DAC488 Personal488 series Serial Communication Boards IEEE 488 Specifications Interface Subsets: SH1, AH1, T6, TE6, L4, LE4, SR1, PP0, RL0, DC1, DT2, C0, and E2 Connector: Standard IEEE 488 connector with metric studs p. 243 p. 246 p. 252 p. 263 p. 297 Q U I C K F I N D For up-to-date information on products, and to order online, visit the IOtech Web site and enter the corresponding page number in the QUICK FIND field. SHOP ON LINE CA-89, Shielded cable with male DB9 connectors for DAC488HR analog output, 6 ft. CA-90, Ribbon cable with male DB15 connector for DAC488HR digital I/O, 6 ft. * Memory expansion modules are ordered on a per channel basis. They must be installed and calibrated at the factory. Contact factory for details. Q U I C K tel: 440-439-4091 fax: 440-439-4093 251 F I N D [email protected] www.iotech.com IEEE 488 Data Acquisition Instruments Specifications