LTC1562-2 Linear Technology, LTC1562-2 Datasheet
LTC1562-2
Related parts for LTC1562-2
LTC1562-2 Summary of contents
Page 1
... dual 4th order Butterworth lowpass filter with 90dB signal-to-noise ratio from a single 5V power supply. Low level signals can exploit the built-in gain capability of the LTC1562-2. Varying the gain of a section can achieve a dynamic range as high as 114dB with a 5V supply. ...
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... LTC1562 ABSOLUTE MAXIMUM (Note 1) + – Total Supply Voltage ( .............................. 11V Maximum Input Voltage – at Any Pin ....................(V – 0.3V Storage Temperature Range ................. – 150 C Operating Temperature Range LTC1562C-2 ............................................ LTC1562I-2 ........................................ – Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL CHARACTERISTICS ...
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... 2.0 1.5 1.0 0 – 0.5 –1 2.5 –1.5 –2 –2.5 –3.0 120 140 160 180 200 220 240 280 NOMINAL f (kHz) O LTC1562-2 = 175kHz. O MIN TYP MAX – 100 – 82 1.5 1.0 2.5 – 100 5 Q Error vs Nominal ...
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... LTC1562 TYPICAL PERFOR A CE CHARACTERISTICS Q Error vs Nominal 2.5V 2 – 5 100 120 140 160 180 200 220 240 260 280 300 NOMINAL f (kHz) O 1562-2 G04 LP Noise vs Nominal f ...
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... V A small pull-up current source at the SHDN input defaults 0.1 F the LTC1562-2 to the shutdown state if the SHDN pin is left floating . Therefore, the user must connect the SHDN pin to a logic “low” (0V for 5V supplies, V supply) for normal operation of the LTC1562-2. (This convention permits true “ ...
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... LTC1562 PIN FUNCTIONS INV A, INV B, INV C, INV D: Each of the INV pins is a virtual- ground summing point for the corresponding 2nd order section. For each section, all three external components Z , R2, R connect to the INV pin as shown in Figure 3 and IN Q described further in the Applications Information. Note ...
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... External resistors R2 and R as follows: will be 200kHz 0. 7958 and C = 100pF are internal to the LTC1562-2 (whose IN while R2 and R A typical design procedure proceeds from the desired f and Q as follows, using finite-tolerance fixed resistors. First find the ideal R2 value for the desired f ...
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... THD and other effects. At the other extreme, a lower f limit of 20kHz reflects an arbitrary O upper resistor limit The LTC1562-2’s MOS input circuitry can accommodate higher resistor values than this, but junction leakage current from the input protection circuitry may cause DC errors. ...
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... The LTC1562-2 can C IN still be used with high performance in such situations as long as this constraint is followed For an LTC1562-2 section as in Figure 3, the magnitudes OUT INV the two outputs V2 and V1 frequency = 2 f, have 2nd ORDER the ratio, 1/4 LTC1562-2 ...
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... The LTC1562-2 fundamentally responds to input current and the external voltage V across the external impedance Z To accept beyond-the-supply input voltages impor- tant to keep the LTC1562-2 powered on, not in shutdown mode, and to avoid saturating the output of the above O 2nd order section that receives the input. If any of these ...
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... R R INA INB INV V1 2nd ORDER 1/4 LTC1562-2 Figure 9. Lowpass “T” Input Circuit The procedure therefore is to begin with the target extra pole frequency f . Determine the series value R P gain requirement. Select a capacitor value C = 1/( greater than ...
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... Further circuit techniques appear in the LTC1562 final data sheet under the heading “Notches and Elliptic Re- sponses.” These techniques are directly applicable to the LTC1562-2 with the substitution of the different values for the internal components R1 and C. In the LTC1562- 7958 and C is 100pF. C 82pF ...
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... INV D R 15k IN4 C *GROUND ALSO AT PINS & 17 Amplitude Response 10 0 – 10 – 20 – 30 – 40 – 50 – 60 – 70 – 80 – 90 10k 100k FREQUENCY (Hz) 1562-2 TA05b LTC1562-2 V OUT1 R 7.68k Q2 R22 6.34k * R24 6.34k R 7.68k Q4 V OUT2 220pF IN4 1562-2 TA05a 1M 13 ...
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... IN2 1 20 INV B INV C R 78. R21 31.6k R22 30. – V LTC1562 SHDN AGND R23 35.7k R24 28. 142k INV A INV D C IN3 R 221k 10pF IN4 – ...
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... U TYPICAL APPLICATIONS LTC1562-2 9th Order 200kHz Lowpass Elliptic Filter R IN2 R R IN1A IN1B 4.02k 4.02k 1 V INVB IN R 6.04k Q1 2 180pF V1B R21 8.06k 3 V2B LTC1562-2 0 SHDN 8 V2A R23 12.4k 9 V1A R 5.36k R 10.2k Q3 IN3 10 INVA C PINS 4, 7, 14, 17 (NOT SHOWN) ALSO CONNECT TO V ...
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... V OUT 1562-2 TA04a Group Delay Response 100 150 200 250 300 350 400 FREQUENCY (kHz) 1562-2 TA04c COMMENTS Clock Tuned No External Components, SO8 Same Pinout as LTC1562-2 15622f LT/TP 0599 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1998 ...