LT6402-6 Linear Technology Corporation, LT6402-6 Datasheet
LT6402-6
Related parts for LT6402-6
LT6402-6 Summary of contents
Page 1
... It can be used as a differential ADC driver, a general-purpose differential gain block other applications requir- ing differential drive. The LT6402-6 can be used in data acquisition systems required to function at frequencies down to DC. The LT6402-6 operates supply and consumes 30mA. ...
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... LT6402-6 ABSOLUTE MAXIMUM RATINGS (Note 1) Total Supply Voltage ( CCA CCB ...................................................5.5V EEA EEB EEC Input Current (+INA, –INA, +INB, –INB, , ENABLE) ................................................±10mA V OCM Output Current (Continuous) +OUT, –OUT ...................................................±100mA +OUTFILTERED, –OUTFILTERED ......................±30mA Output Short-Circuit Duration (Note 2) ............ Indefi nite Operating Temperature Range (Note 3).... –40°C to 85°C Specifi ...
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... Single-Ended Differential (+OUT, –OUT 1.2V to 3.6V OCM Differential (+OUT, –OUT 1.4V to 3.4V OCM Single-Ended Measured from V to Average of +OUT and –OUT OCM ENABLE = 0.8V ENABLE = 2V ENABLE = 0.8V ENABLE = 5.5V LT6402-6 = 0V, ENABLE = 0.8V, +INA = EEA EEB EEC unless otherwise noted. LOAD MIN TYP MAX l 2.5 l –0 ...
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... LT6402-6 AC ELECTRICAL CHARACTERISTICS ⎯ E ⎯ N ⎯ A ⎯ B ⎯ L ⎯ 0.8V, +INA shorted to +INB (+IN), –INA shorted to –INB (–IN), V unless otherwise noted. SYMBOL PARAMETER Input/Output Characteristics –3dBBW –3dB Bandwidth 0.1dBBW Bandwidth for 0.1dB Flatness 0.5dBBW Bandwidth for 0.5dB Flatness SR Slew Rate t 1% Settling s1% ...
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... The LT6402I is guaranteed to meet specifi ed performance from –40°C to 85°C. Note 5: Since the LT6402 feedback amplifi er with low output impedance, a resistive load is not required when driving an ADC. Therefore, typical output power is very small. In order to compare the ...
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... LT6402-6 TYPICAL PERFORMANCE CHARACTERISTICS Third Order Intermodulation Distortion vs Frequency, Differential Input LOAD –45 2 TONES 2V COMPOSITE P-P –55 1MHz TONE SPACING UNFILTERED –65 OUTPUTS –75 FILTERED –85 OUTPUTS –95 –105 FREQUENCY (MHz) 64026 G04 Output Third Order Intercept vs Frequency, Differential Input 400Ω ...
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... PSRR 90 80 CMRR 100 1000 FREQUENCY (MHz) 64026 G20 LT6402-6 Reverse Isolation vs Frequency 0 UNFILTERED OUTPUTS –20 –40 –60 –80 –100 –120 1 10 100 1000 FREQUENCY (MHz) 64026 G15 Input Refl ection Coeffi cient vs Frequency 0 ...
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... OUT P-P –70 –75 –80 HD2 –85 HD3 –90 –95 –100 1.0 1.2 1.4 1.6 1.8 2.0 2.2 OUTPUT COMMON MODE VOLTAGE (V) 10MHz 8192 Point FFT, LT6402-6 Driving an LTC2249 14-Bit ADC 0 8192 POINT FFT – 10MHz, –1dBFS IN –20 FILTERED OUTPUTS –30 –40 –50 –60 –70 –80 –90 –100 –110 – ...
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... V pin. If low, the LT6402-6 is enabled and draws CC EEC typically 30mA of supply current. If high, the LT6402-6 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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... V CCB CCC EEA Referring to the block diagram, the LT6402-6 uses a closed-loop topology which incorporates 3 internal am- plifi ers. Two of the amplifi ers (A and B) are identical and drive the differential outputs. The third amplifi used to set the output common mode voltage. Gain and input impedance are set by the 200Ω ...
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... In addition, there is generally some form of lowpass or bandpass fi ltering just prior to the 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 LT6402-6 can easily drive the SINGLE-ENDED 133Ω – ...
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... Figure 4. Adding Small Series R at LT6402-6 Output Filtered Applications (Using the +OUTFILTERED and –OUTFILTERED Pins) Filtering at the output of the LT6402-6 is often desired to provide either anti-aliasing or improved signal to noise ratio. To simplify this fi ltering, the LT6402-6 includes an additional pair of differential outputs (+OUTFILTERED and – ...
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... F08 Figure 8. LT6402-6 Output Filter Modifi ed for Bandpass Filtering (1 External Inductor, 1 External Capacitor) Output Common Mode Adjustment The LT6402-6’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 ...
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... LTC1748 family of 14-bit low-noise ADCs. This additional output swing improves system SNR 4dB. Input Bias Voltage and Bias Current The input pins of the LT6402-6 are internally biased to the voltage applied to the V pin. No external biasing OCM resistors are needed, even for AC-coupled operation. The ...
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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 (4 SIDES) 1.45 ± 0.10 (4-SIDES) 0.200 REF 0.00 – 0.05 LT6402-6 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 ...
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... R10 ENABLE EEC CCB EEB 24.9Ω –INB –OUT R8 [ –INA –OUTFILTERED L1 R7 LT6402-6 [1] [ +INB +OUTFILTERED R9 24.9Ω +INA +OUT CCC OCM CCA EEA ...