LT1256 Linear Technology Corporation, LT1256 Datasheet

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... This is ideal for fader applications because it eliminates off-channel feedthrough due to offset or gain errors in the control signals. The LT1256 does not have this on/off feature and operates linearly over the complete control range. The LT1256 is recommended for applications requiring more than 20dB of linear control range ...

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... TOP VIEW NUMBER IN2 – – FB2 13 CONTROL LT1251CN LT1251CS C FS – – LT1256CN FS R LT1256CS (Note OUT S PACKAGE 14-LEAD PLASTIC SO = 150 ( 150 C, = 100 2.5V NULL = Open, Pins 5,10 = GND ...

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... – 5V 3V – 5V 3V 15V 15V 15V S LT1251/LT1256 = 2.5V NULL = Open, Pins 5,10 = GND MIN TYP MAX 0.03 0. 150 300 2 0.02 0.90 0.02 0.55 0.002 0.015 ...

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... are available on special request. Consult factory. Note calculated from the ambient temperature T J dissipation P according to the following formulas: D LT1251CN/LT1256CN • LT1251CS/LT1256CS • 100 C/ 2.5V NULL = Open, Pins 5,10 = GND, unless otherwise noted CONDITIONS V = – ...

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... P 2. –40 –50 3RD 2ND –60 – 100 FREQUENCY (MHz) 1251/56 G09 LT1251/LT1256 Spot Input Noise Voltage and Current vs Frequency 100 – 100 1k 10k FREQUENCY (Hz) 1251/56 G06 Undistorted Output Voltage vs Frequency ...

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... LT1251/LT1256 W U TYPICAL PERFORMANCE CHARACTERISTICS Bandwidth vs Feedback Resistance 100 PEAKING 0.5dB PEAKING 5.0dB ±15V ± 0.6 0.8 1.0 1.2 1.4 1.6 1.8 FEEDBACK RESISTANCE (k ) 1251/56 G11 Bandwidth vs Feedback Resistance 10 100 PEAKING 0.5dB PEAKING 5.0dB ±15V ± ...

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... Voltage vs Load Current 3 ± 25°C 2 –55° 125°C 1.5 A 1.0 0.5 0 –10 –20 –30 –40 LOAD CURRENT (mA) 1251/56 G27 LT1251/LT1256 Input Common Mode Range vs Temperature + – – 2 – – – V –50 – 100 ...

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... LT1251/LT1256 W U TYPICAL PERFORMANCE CHARACTERISTICS Slew Rate vs Full-Scale Reference Voltage 350 300 V = 15V S 250 200 150 100 0.5 1.0 1.5 2.0 2.5 FULL-SCALE REFERENCE VOLTAGE (V) 1251/56 G29 Settling Time to 10mV vs Output Step ±15V 1. INVERTING, 2 NONINVERTING 0 –2 INVERTING –4 –6 NONINVERTING – ...

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... FS Q14 Q31 Q30 Q32 Q38 Q36 Q37 Q41 Q40 Q44 FB1 IN2 Q42 Q46 Q43 Q48 Q49 Q50 Q33 Q34 Q35 LT1251/LT1256 V CC Q19 Q20 + I 5 Q16 Q17 Q13 Q18 R3 R4 250 250 I Q15 ...

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... These components must be within an inch of the IC in order to be effective. All of the inputs to the LT1251/LT1256 have ESD protec- tion circuits. During normal operation these circuits have no effect. If the voltage between the noninverting and inverting inputs exceeds 6V, the protection circuits will trigger and attempt to short the inputs together ...

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... The curves show the details. Distortion When only one input is contributing to the output (V or 100%) the LT1251/LT1256 have very low distortion. As the control reduces the output, the distortion will increase. The amount of increase is a function of the current that flowing FS flows in the inverting input ...

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... Figure 2 is the basic block diagram of the LT1251/LT1256 signal path with external resistors R Both input stages are operating as noninverting amplifiers with two input signals V and Each input stage has a unity-gain buffer from the nonin- verting input to the inverting input. Therefore, the inverting input is at the same voltage as the noninverting input ...

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... G 2 Again set R error at low frequencies) the above equation simplifies to: ) and Pin where A The 4-resistor difference amplifier yields the same result as the inverting amplifier case, and the common mode rejection is independent of K. LT1251/LT1256 1 and get ...

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... The collector current is essentially C the same as the emitter current and it is the ratio of the two collector currents that sets the gain. The LT1251/LT1256 are tested with Pins 5 and 10 grounded and a full-scale voltage of 2.5V applied to V sets I at approximately 500 A; the control voltage V FS applied to Pin 3 ...

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... FS FS – 1.5k 1. OUT 220k + V – + 1251/56 TA03 – V Single Supply Noninverting AC Amplifier with Digital Gain Control 1.5k 1.5k LT1251/LT1256 2 – – – 10k 10k 20k ...

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... INPUT VOLTAGE OUTPUT RESISTANCE DEPENDS OUT MATCHING OF RESISTORS Variable Lowpass, Highpass and Allpass Filter BASIC VARIABLE INTEGRATOR R C 1.5k LT1256 2 – – 1. ...

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... V FS –15 0 1.25 2.5 CONTROL VOLTAGE (V) 1251/56 TA07b 2. <1dB ERROR 24dB – 0 –15 0 1.25 2.5 CONTROL VOLTAGE (V) 1251/56 TA08b Basic Variable Integrator 1.5k LT1256 2 – – 1. –1 R 10k ...

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... 2. 100pF 1251/56 TA14a ' ' 430 430 ' 50pF 150 910 100pF LT1256 – – 2. 100pF ' R 12, 10k ' OUT 1.00 ...

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... 1. 2.0 2.5 1251/56 TA15b LT1251/LT1256 OUT 500pF 1k 1.5k LT1256 2 – – 1. 500pF 1251/56 TA15a 2. Control Voltage 2. ...

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... LT1251/LT1256 W W ACRO ODEL TM For PSpice * * Linear Technology LT1251/LT1256 VIDEO FADER MACROMODEL * Written: 3-11-1994 BY WILLIAM H. GROSS. * Corrected: 7-15-1996 * Connections: as per datasheet pinout *1=first noninverting input *2=first inverting input *3=control voltage input *4=control current input *5=control resistor, RC *6=null input *7=negative supply *8=output ...

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... RFS C10 10 0 1PF * *generating K *** the next two lines are for the LT1251 TABLE {I(VOSC)/I(VOSFS)}= (–100,0) + *** the next two lines are for the LT1256 * TABLE {I(VOSC)/I(VOSFS)}= (–100,0) *+ RDUMMY K 0 1MEG RNOISE1 EN 0 200K RNOISE2 EN 0 200K *generates 40 ...

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... OUTPUT STAGE AND VOLTAGE SWING/CURRENT LIMIT 1. 3.4pF LT1251/LT1256 Macro Model for PSpice 1pF C13 13B 1pF OSC 1pF 1pF ...

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... MIN 0.100 0.010 (2.540 0.254) S Package 14-Lead Plastic Small Outline (Narrow 0.150) (LTC DWG # 05-08-1610) 0.004 – 0.010 (0.101 – 0.254) 0.228 – 0.244 (5.791 – 6.197) 0.050 (1.270) TYP LT1251/LT1256 0.770* (19.558) MAX 0.255 0.015* (6.477 0.381) 1 ...

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... Low Cost Video Amplifier LT1253/LT1254 Low Cost Dual and Quad Video Amplifiers LT1259/LT1260 Low Cost Dual and Triple 130MHz Current Feedback Amplifiers with Shutdown Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 : (408) 434-0507 FAX TELEX LT1256 – CONTROL – ...