for additional information regarding custom microelectronic products and services, please contact micro networks at: models md3902/3905/3910 are high- performance, precision 2/5/10mhz full- scale voltage-to-frequency converters, intended for those applications that require maximum performance at the most economical cost. these converters feature >126/134/142-db dynamic range, 0.01/0.02/0.05% linearity, and 5% overrange capability. the md3902/3905/ 3910 devices feature overall performance and stability virtually identical to that of similar units costing 40% or more. all models accept a -100 m v to -10v full-scale single-ended analog input signal that is converted to an output signal whose frequency is proportional to the full-scale frequency, within 0.01/0.02/ 0.05% linearity, using the long-proven charge-balance technique. the devices offer 5% overrange capability, and buffered complimentary ttl-compatible frequency outputs that will drive capaci- tive loads as high as 50 pf. stability of the md3902/3905/3910 series is excellent for v/f converters in the respective price ranges, with 10 m v/ c typical, 30 m v/ c maximum offset and 60 ppm/ c typical, 100 ppm/ c maxi- mum gain temperature coefficients. warm-up time to specified accuracy is less than two minutes. in applications where overall system throughput must be maintained at a specific rate, or where fixed offset or different scale voltages would be more convenient, custom frequencies and/or custom trimming can be easily accommo- dated. by increasing the full-scale output frequency by 10 to 20%, for example, additional time would be available for the system microprocessor to access the results of each conversion. please contact the factory to discuss your specific timing requirements. all models are packaged in a 1.31" x 0.69" x 0.22" 24-pin ceramic dil package. power dissipation is lower than 0.65/0.80/0.85 watts, and operation to specified accuracy is guaranteed over the 0 c to +70 c temperature range. n outstanding price/ performance ratio n guaranteed minimum/ maximum specifications n wide dynamic range >2,000,000/5,000,000/ 10,000,000:1 >126/134/142 db n excellent linearity 0.01/0.02/0.05% fsr 0.01/0.02/0.05% of input n excellent stability 10 m v/ c offset 60 ppm/ c gain n voltage or current inputs n offset and gain error trimmable to zero n complementary frequency outputs-ttl/cmos compatible n small 24-pin dip n low power <0.65/0.80/0.85w features: 324 clark st., worcester, ma 01606 tel. (508) 852-5400 ? fax (508) 853-8296 e-mail C sales@mnc.com web site C http://www.mnc.com n precision integration n digital data transmission n frequency synthesis n analytical instrumentation n medical instrumentation n telemetry n data recording n weighing systems n tachometers n accelerometers n flow meters n robotics applications: md3902/3905/3910 2/5/10mhz v/f converters free datasheet http://www.ndatasheet.com
ordering information part number md3902 MD3905 md3910 2mhz full-scale 5mhz full-scale 10mhz full-scale 15 6 6 7 absolute maximum ratings operating temperature range 0 c to +70 c storage temperature range -65 c to +150 c +15v supply (pin 1) +15.45 volts -15v supply (pin 5) -15.45 volts +5v supply (pin 20) +5.25 volts analog input (pin 11) -15 volts to +15 volts analog inputs input voltage range nonsaturating overrange configuration input impedance md3902 MD3905 md3910 offset voltage (trimmable to zero) transfer characteristics full-scale output md3902 MD3905 md3910 transfer function md3902 MD3905 md3910 gain error (trimmable to zero) nonlinearity (max.) md3902 (not specified under MD3905 overrange conditions) md3910 full-scale step response md3902 (maximum; to 0.01%) MD3905 md3910 overload recovery md3902 MD3905 md3910 stability gain temperature coefficient offset temperature coefficient power supply rejection gain offset warm-up time (to specified accuracy) output pulse width md3902 MD3905 md3910 logic levels: logic 1 logic 0 (3 ma sink) power supply requirements 15v supplies +5v supply +15v current drain md3902 MD3905 md3910 -15v current drain +5v current drain md3902 MD3905 md3910 power dissipation md3902 MD3905 md3910 specifications @ t a = +25 c, supplies = 15v and +5v, unless otherwise indicated specifications min. typ. max. units 5 2 5 10 200 80 35 +3.5 14.55 +4.75 volts % k w k w k w mv mhz mhz mhz % ppm of fsr/ c ppm of fsr/ c ppm of fsr/%vs m v/%vs minutes nsec nsec nsec volts volts volts volts ma ma ma ma ma ma ma mw mw mw specifications subject to change without notification as micro networks reser ves the right to make improvements and changes in its products. 324 clark st., worcester, ma 01606 tel. (508) 852-5400 ? fax (508) 853-8296 e-mail C sales@mnc.com web site C http://www.mnc.com 60 10 250 100 50 +4.0 0.01%fs 0.01%v in 0.02%fs 0.02%v in 0.05%fs 0.05%v in 2 cycles of new f out + 20 m sec 2 cycles of new f out + 10 m sec 2 cycles of new f out + 5 m sec 8 cycles of new f out 10 cycles of new f out 12 cycles of new f out 0 to -10 2mhz?(v in / 10v) 5mhz?(v in / 10v) 10mhz?(v in / 10v) single-ended 10 1 100 30 200 10 2 300 120 65 +4.5 0.4 15.45 5.25 20 30 30 10 40 40 50 650 800 850 md3902/3905/3910 2/5/10mhz v/f converters free datasheet http://www.ndatasheet.com
324 clark st., worcester, ma 01606 tel. (508) 852-5400 ? fax (508) 853-8296 e-mail C sales@mnc.com web site C http://www.mnc.com using the md39xx general considerations C figure 2 depicts a typical circuit configuration for the md39xx. the layout should be clean, with output pulses routed as far away from the input analog signals as possible. to obtain maximum performance, bypass capacitors, as shown in figure 2, should be mounted right at the appropriate pins of the md39xx. figure 2. typical circuit configuration. offset and gain trimming C the offset adjustment potentiometer should be a 20k w , 10-turn unit. to ensure that the temperature coefficient of the potentiometer does not become significant relative to the overall offset tempco specification, a 100ppm or better potentiometer is recommended. with this pot in the circuit, initial offsets of up to 10mv may be trimmed to zero. the gain adjustment potentiometer should be a 200 w , 10-turn unit with a recommended tempera- ture coefficient of 100ppm or better. with this pot in the circuit, initial gain errors of up to 2% may be trimmed to zero. grounding C the analog and digital grounds are internally separated in the md39xx. the use of ground plane is not necessary for proper operation of the md39xx. however, a ground plane is recommended with any analog signal conditioning circuitry that may be used in front of the v/f, especially if this circuitry involves high gains. any amplifiers used ahead of the md39xx should be decoupled to eliminate potential problems with the high-frequency output of the v/f. block diagram offset tr i m i in v in integrator (8) (10) (11) (1) +15v (2,3,4) agnd (5) -15v (20) +5v (22) dgnd (23,24) output (21) output buffers schmidt trigger + - charge pump 24 23 21 20 22 1 2 3 4 8 11 20k 10-turn <100 ppm/ 200k 10-turn <100 ppm/ analog ground offset tr i m gain adjust f out +5v digital ground +15v -15v 6.8 f 6.8 f 6.8 f 5 f out md3902/3905/3910 2/5/10mhz v/f converters free datasheet http://www.ndatasheet.com
13 24 12 pin 1 324 clark st., worcester, ma 01606 tel. (508) 852-5400 ? fax (508) 853-8296 e-mail C sales@mnc.com web site C http://www.mnc.com revision 1 5/98 - 5m ? copyright 1998 1 +15v supply 2 analog ground 3 analog ground 4 analog ground 5 -15v supply 6 no connect 7 no connect 8 offset trim 9 no connect 10 i in 11 v in 12 no connect 24 output 23 output 22 digital ground 21 output 20 +5v supply 19 no connect 18 no connect 17 no connect 16 no connect 15 no connect 14 no connect 13 no connect pin designations offset and gain calibra tion offset calibration C offset calibration should be performed prior to gain calibration. with a -10mv analog input signal at pin 11 of the md39xx, adjust the offset potentiometer until a frequency of 2.000/5.000/10.000khz is observed on output pins 21, 23 or 24. gain calibration C with a full scale analog input voltage of -10.00v on pin 11, adjust the gain potentiometer until a full-scale frequency of 2.000/5.000/10.000mhz is observed on output pin 21, 23 or 24. n/c pins C pins marked as no connect have no electrical connection to the internal circuitry of the md39xx. output pins C pins 23 and 24 are tied together internally. either or both may be used as the source of the frequency output of the md39xx, as long as the load specifications are not exceeded. pin 21 provides a complementary signal relative to pins 23 and 24 with similar loading limits. md3902/3905/3910 2/5/10mhz v/f converters free datasheet http://www.ndatasheet.com
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