shm-950 miniature, high-speed 0.001% sample-hold amplifiers i n n o v a t i o n a n d e x c ell e n c e ? ? fea tures 18-bit accuracy small 8-pin dip package 800ns max. acquisition time to 0.001% 200ns max. sample-to-hold settling time to 0.001% 16mhz small signal bandwidth 90db feedthrough attenuation 25 picoseconds aperture uncertainty 415mw maximum power dissipation general description datel?s shm-950 is a high-speed, highly accurate sample/ hold designed for precision, high-speed analog signal processing applications. the shm-950 features excellent dynamic specifications including a maximum acquisition time of only 800 nanoseconds for a 10v step to 0.001%. sample-to-hold settling time, to 0.001% accuracy, is 200 nanoseconds maximum with an aperture uncertainty of 25 picoseconds. the shm-950 is a complete sample/hold circuit, containing a precision mos hold capacitor and a mosfet switching configuration which results in faster switching and better feedthrough attenuation. additionally, a fet input amplifier design allows faster acquisition and settling times while maintaining a considerably lower droop rate. input/output connections pin function 1 +5v suppl y 2 s/h control 3 analog input 4 analog return 5 ?15v suppl y 6 analog output 7 +15v suppl y 8 power ground figure 1. shm-950 functional block diagram ?15v supply +15v supply 3 2 power ground switch driver 6 analog output 2k w analog input s/h control 4 8 +5v supply analog return 5 1 7 2k w 100pf
shm-950 ? ? power requirements min. typ. max. units voltage range +15v supply +11.5 +15.0 +15.5 volts ?15v supply ?11.5 ?15.0 ?15.5 volts +5v supply +4.75 +5.0 +5.25 volts power supply rejection ratio ? 0.5 1 mv/v quiescent current drain +15v supply ? +8 +13.5 ma ?15v supply ? ?8 ?13.5 ma +5v supply ? +1 +1.5 ma power consumption ? 365 415 mw physical/environmental operating temp. range, case SHM-950MC 0 to +70c shm-950mm ?55 to +125c storage temperature range ?65 to +150c thermal impedance q jc 15c/w q ca 35c/w package type 8-pin ceramic dip absolute maximum ra tings 15v supply voltage 18v +5v supply voltage ?0.5v to +7v analog input 18v digital input ?0.5v to +5.5v output current 65 ma functional specifica tions (apply over the operating temperature range with 15v and +5v supplies unless otherwise specified.) model opera ting temp . range SHM-950MC 0 to +70c shm-950mm ?55 to +125c for availability of high-reliability versions of the shm-950, contact datel. ordering informa tion footnotes: full scale (fs) = 10v. full scale range (fsr) = 20v. sample-to-hold offset error (pedestal) is constant regardless of input/output level. technical notes 1. all ground pins should be tied together and connected to system analog ground as close to the package as possible. it is recommended to use a ground plane under the device and solder ground pins directly to it. take care to ensure that no ground potentials can exist between ground pins. 2. external 0.1f to 1f tantalum bypass capacitors are required in critical applications. 3. a logic 1 on s/h puts the unit in the sample mode. a logic 0 puts the unit in hold mode. 4. the maximum capacitive load to avoid oscillation is typically 250pf. recommended resistive load is 500 w , although values as low as 250 w may be used. acquisition and sample-to-hold settling times are relatively unaffected by resistive loads down to 250 w and capacitive loads up to 50pf. greater load capacitances will affect both acquisition and settling time. 5. gain and offset adjusting can be accomplished using the external circuitry shown in figure 2. adjust offset with a 0v input. adjust gain with a fs input. adjust so that the output in the hold mode matches the input. analog input/output min. typ. max. units input/output voltage range 15v nominal supplies 10 11.5 ? volts 12v nominal supplies 7 8.5 ? volts input impedance 1.75 2 ? k w output current ? ? 40 ma output impedance ? 0.1 ? w capacitive load 100 250 ? pf digital input input logic levels logic 1 +2.0 ? +5.0 volts logic 0 0 ? +0.8 volts loading logic 1 ? ? +5 a logic 0 ? ? ?5 a transfer characteristics gain ? ?1 ? v/v gain error, +25c ? 0.05 0.5 % linearity error ? 0.001 0.005 %fs sample mode offset , +25c ? 2 7 mv sample-to-hold offset (pedestal), +25c ? 2.5 25 mv gain drift ? 0.5 15 ppm/c sample mode offset drift ? 3 15 ppm of fsr/c sample-to-hold off. (pedestal) drift ? 5 20 ppm of fsr/c dynamic characteristics acquisition time 10v to 0.001%fs (0.1mv) +25c ? 160 800 ns ?55 to +125c ? ? 900 ns 10v to 0.1%fs (10 mv) +25c ? 100 400 ns ?55 to +125c ? ? 450 ns 10v to 1%fs (100 mv) ? 200 ? ns 1v to 1%fs (10 mv) ? 200 ? ns sample-to-hold settling time 10v to 0.01%fs (1 mv) ? 100 150 ns 10v to 0.1%fs (10 mv) ? 100 120 ns sample-to-hold transient ? 100 ? mvp-p aperture delay time ? 10 15 ns aperture uncertainty (jitter) ? 25 50 ps output slew rate 40 60 ? v/s output droop +25c ? 0.5 15 v/s 0 to +70c ? 15 30 v/s ?55 to +125c ? 1.2 2.4 mv/s feedthrough rejection ? ?84 ?78 db
shm-950 ? ? mechanical dimensions inches (mm ) figure 2. offset and gain adjustments 0.300 max. (7.62) dimension tolerances (unless otherwise indicated): 2 place decimal (.xx) 0.001 (0.25) 3 place decimal (.xxx) 0.005 (0.127) 0.405 max. (10.287) 0.140 max. (3.556) 0.300 0.015 (7.620) 0.300 0.005 (7.620) 0.054 (1.372) 0.010 0.002 (0.254) 0.100 typ. (2.540) 0.018 0.002 (0.457) 0.035 0.010 (0.89) 0.200 max. (5.08) shm-49 pin 1 indentifier 0.09 (2.23) ? ? innov a tion and ex cellence datel makes no representation that the use of its products in the circuits described herein, or the use of other technical information contained herein, will not infringe upon existing or future patent rights. the descriptions contained herein do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. specifications are subject to change without notice. the datel logo is a registered datel, inc. trademark. ds-0484 07/2000 datel, inc. 11 cabot boulevard, mansfield, ma 02048-1151 tel: (508) 339-3000 (800) 233-2765 fax: (508) 339-6356 internet: www.datel.com e-mail: sales@datel.com datel (uk) ltd. tadley, england tel: (01256)-880444 datel s.a.r.l. montigny le bretonneux, france tel: 01-34-60-01-01 datel gmbh mnchen, germany tel: 89-544334-0 datel kk tokyo, japan tel: 3-3779-1031, osaka tel: 6-6354-2025 note: with a precision source, adjust r1 and r2 so that the output of the shm-950 in the hold mode matches the source output. shm-950 ?15v +15v high-speed fast-settling amplifier analog input (offset adjust) r1 10k w , 0.1% 10k w , 0.1% 50 w 3m w 5.11k w r2 (gain adjust) to shm-950 pin 3 iso 9001 registered
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