lt1993-2 Linear Technology Corporation, lt1993-2 Datasheet
lt1993-2
Related parts for lt1993-2
lt1993-2 Summary of contents
Page 1
... It can be used as a differential ADC driver, a general-purpose differential gain block any other application requir- ing differential drive. The LT1993-2 can be used in data acquisition systems required to function at frequencies down to DC. The LT1993-2 operates supply and consumes 100mA. It comes in a compact 16-lead 3 × ...
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... LT1993 ABSOLUTE AXI U RATI GS (Note 1) Total Supply Voltage ( CCA CCB ...................................................5.5V EEA EEB EEC Input Current (+INA, –INA, +INB, –INB ENABLE) ................................................±10mA OCM Output Current (Continuous) (Note 6) +OUT, –OUT (DC) ..........................................±100mA (AC) ..........................................±100mA +OUTFILTERED, –OUTFILTERED (DC) .............±15mA Output Short Circuit Duration (Note 2) ............ Indefi nite Operating Temperature Range (Note 3) ... – ...
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... Differential (+OUT, –OUT) P-P 200mV Differential (+OUT, –OUT) P-P 3.2V Differential (+OUT, –OUT) P-P 1% Settling for a 1V Differential Step P-P (+OUT, –OUT) 0. Measured Single-Ended at +OUT P-P OCM and –OUT 1.3V to 3.4V Step at V OCM LT1993 0V, ENABLE = 0.8V, +INA EEA EEB EEC unless otherwise noted. LOAD MIN TYP MAX 0.3 0.8 0.9 1 1.1 ● 0.9 1.1 1.1 ● ...
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... LT1993-2 AC ELECTRICAL CHARACTERISTICS ENABLE = 0.8V, +INA shorted to +INB (+IN), –INA shorted to –INB (–IN), V unless otherwise noted. SYMBOL PARAMETER Noise/Harmonic Performance Input/output Characteristics 1kHz Signal Second/Third Harmonic Distortion Third-Order IMD OIP3 Output Third-Order Intercept 1k e Input Referred Noise Voltage Density n1k 1dB Compression Point ...
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... QA sampled at these temperatures. The LT1993I-2 is guaranteed to meet specifi ed performance from –40°C to 85°C. Note 5: This parameter is pulse tested. Note 6: This parameter is guaranteed to meet specifi ed performance through design and characterization. It has not been tested. LT1993 0V, EEA ...
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... LT1993 TYPICAL PERFOR A CE CHARACTERISTICS Frequency Response R = 400Ω LOAD 12 9 UNFILTERED OUTPUTS 6 FILTERED OUTPUTS 3 0 – 100mV IN P-P UNFILTERED 400Ω LOAD –6 FILTERED LOAD 350Ω (EXTERNAL) + –9 50Ω (INTERNAL, FILTERED OUTPUTS) – 100 1000 10000 FREQUENCY (MHz) ...
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... HD2 UNFILTERED OUTPUTS –65 –70 –75 –80 –85 HD2 FILTERED OUTPUTS –90 HD3 FILTERED OUTPUTS –95 –100 11 – OUTPUT AMPLITUDE (dBm) LT1993-2 Distortion (Filtered) vs Frequency Differential Input, R LOAD –10 FILTERED OUTPUTS –20 P-P OUT –30 –40 –50 –60 –70 –80 –90 – ...
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... LT1993 TYPICAL PERFOR A CE CHARACTERISTICS Distortion (Filtered) vs Frequency Single-Ended Input LOAD –10 FILTERED OUTPUTS –20 P-P OUT –30 –40 HD3 –50 –60 HD2 –70 –80 –90 –100 –110 1 10 100 1000 FREQUENCY (MHz) 19932 G19 Distortion (Unfi ltered) vs Frequency, Single-Ended Input, ...
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... Output Refl ection Coeffi cient vs Frequency 0 MEASURED USING DC800A DEMO BOARD –5 –10 –15 –20 –25 –30 –35 –40 –45 –50 1000 10 100 FREQUENCY (MHz) LT1993-2 Input Referred Noise Voltage vs Frequency 1000 10 100 FREQUENCY (MHz) 19932 G29 Differential Output Impedance vs Frequency 100 ...
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... R = 100Ω PER OUTPUT LOAD 2.26 2.24 2.22 2.20 2.18 2.16 2.14 2. TIME (ns) 19932 G37 Distortion vs Output Common Mode Voltage LT1993-2 Driving LTC2249 14-Bit ADC –64 FILTERED OUTPUTS LOAD V = 70MHz 2V OUT P-P –66 –68 –70 HD3 –72 HD2 –74 –76 1.2 1.4 1.6 1.8 2.0 2.2 2.4 OUTPUT COMMON MODE VOLTAGE (V) ...
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... FREQUENCY (MHz) 19932 G49 50MHz 8192 Point FFT, LT1993-2 Driving LTC2249 14-Bit ADC 0 8192 POINT FFT – 50MHz, –1dBFS IN FILTERED OUTPUTS –20 –30 –40 –50 –60 –70 –80 –90 –100 – ...
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... V pin. If low, the LT1993-2 is enabled and draws CC EEC typically 100mA of supply current. If high, the LT1993-2 is disabled and draws typically 250µA. +INA, +INB (Pins 15, 16): Positive Inputs. These pins are normally tied together. These inputs may be DC- or AC- coupled. If the inputs are AC-coupled, they will self-bias to the voltage applied to the V – ...
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... EEA V 200Ω CCC + C – V EEC 200Ω V CCB + B – V EEB 200Ω BIAS ENABLE V CCB CCC LT1993-2 V EEA 12pF +OUT 5 +OUTFILTERED 6 25Ω V OCM 2 12pF 25Ω –OUTFILTERED 7 –OUT 8 12pF V EEB 9 12 19932 EEA EEB EEC 19932fa ...
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... Low output impedance • Built-in, user adjustable output fi ltering • Requires minimal support circuitry Referring to the block diagram, the LT1993-2 uses a closed- loop topology which incorporates 3 internal amplifi ers. Two of the amplifi ers (A and B) are identical and drive the differential outputs. The third amplifi ...
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... ADC to limit input noise at the ADC, thereby improving system signal to noise ratio. Both the unfi ltered and fi ltered outputs of the LT1993-2 can easily drive the W U high impedance inputs of these differential ADCs. If the fi ...
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... FILTERED OUTPUT LT1993-2 (350MHz) 25Ω 19932 F07 25Ω Figure 9. LT1993-2 Output Filter Topology Modifi ed for Bandpass Filtering (1 External Inductor, 1 External Capacitor) 8 –OUT V EE 12pF 12pF 7 – ...
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... U U APPLICATIO S I FOR ATIO Output Common Mode Adjustment The LT1993-2’s output common mode voltage is set by the V pin high-impedance input, capable of setting OCM the output common mode voltage anywhere in a range from 1.1V to 3.6V. Bandwidth of the V 300MHz, so for applications where the bias voltage, a 0.1µ ...
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... LT1993-2 U TYPICAL APPLICATIO 18 19932fa ...
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... Plastic QFN (3mm × 3mm) (Reference LTC DWG # 05-08-1691) 0.70 ±0.05 PACKAGE OUTLINE 0.25 ±0.05 0.50 BSC 0.75 ± 0.05 3.00 ± 0.10 (4 SIDES) 1.45 ± 0.10 (4-SIDES) 0.200 REF 0.00 – 0.05 LT1993-2 BOTTOM VIEW—EXPOSED PAD PIN 1 NOTCH R = 0.20 TYP R = 0.115 OR 0.25 × 45° CHAMFER TYP 15 16 0.40 ± 0. (UD16) QFN 0904 0.25 ± 0.05 0.50 BSC ...
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... R10 V ENABLE V V EEC CCB EEB 24.9Ω –INB –OUT R8 [ –INA –OUTFILTERED L1 R7 LT1993-2 [1] [ +INB +OUTFILTERED R9 24.9Ω +INA +OUT CCC OCM CCA EEA ...