LTC6420-20 Linear Technology, LTC6420-20 Datasheet
LTC6420-20
Related parts for LTC6420-20
LTC6420-20 Summary of contents
Page 1
... ADCs with low noise and low distortion, but can also be used as a general-purpose broadband gain block. P-P The LTC6420-20 is easy to use, with minimal support circuitry required. The output common mode voltage is set using an external pin, independent of the inputs, which eliminates the need for transformers or AC-coupling capacitors in many applications. The gain is internally fi ...
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... Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: SELECTOR GUIDE PART NUMBER SINGLE DUAL LTC6400-8 LTC6400-14 LTC6400-20 LTC6420-20 LTC6400-26 LTC6401-8 LTC6401-14 LTC6401-20 LTC6421-20 LTC6401-26 2 PIN CONFIGURATION PART MARKING* PACKAGE DESCRIPTION 20-Lead (3mm × ...
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... Differential, Includes Parasitic Differential Input Common Mode Voltage 1.1V to 1.6V OCM V = 1.25V to 1.5V OCM ENABLEx ≤ 0.8V ENABLEx ≥ 2.4V ENABLEx ≤ 0.8V; per Amplifi er ENABLEx ≥ 2.4V; per Amplifi er. Inputs Floating + V = 2.85V to 3.5V LTC6420-20 = 1.25V, ENABLE = 0V unless OCM L MIN TYP MAX UNITS l 19.6 20 20.4 l ±0.1 ±0. ...
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... OUT P-P Note 6: Measured using Test Circuit B. R Note 7: Since the LTC6420- feedback amplifi er with low output impedance, a resistive load is not required when driving an AD converter. Therefore, typical output power is very small. In order to compare the LTC6420-20 with amplifi ers that require 50Ω output load, the output voltage swing driving a given R driving a 50Ω ...
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... G04 250 200 S11 150 S22 100 S12 50 0 100 1000 3000 642020 G06 LTC6420-20 Channel to Channel Phase Match vs Frequency 0.5 0.4 0.3 0.2 0.1 0.0 –0.1 –0.2 –0.3 –0.4 –0.5 1000 2000 10 100 FREQUENCY (MHz) 642020 G02 S21 Phase and Group Delay vs Frequency 1 ...
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... LTC6420-20 www.DataSheet4U.com TYPICAL PERFORMANCE CHARACTERISTICS Noise Figure and Input Referred Noise Voltage vs Frequency NOISE FIGURE 100 FREQUENCY (MHz) 642020 G08 Harmonic Distortion vs Frequency –40 DIFFERENTIAL INPUT OUT P-P –50 –60 –70 –80 – ...
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... 12.5Ω 100Ω – 1000Ω ENABLEB OCMB LTC6420- (Pins 15, 20 Positive Power Supply , V (Pins 19, 8): These pins set the output OCMB – . The Exposed Pad must be +OUTA 17 OUT 16 –OUTA OUT + – – ...
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... Small output resistors of 12.5Ω improve the circuit stability over various load conditions. The LTC6420-20 is very fl exible in terms of I/O coupling. It can be AC- or DC-coupled at the inputs, the outputs or both. If the inputs are AC-coupled, the input common mode voltage is automatically biased close to V circuitry is needed for bias ...
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... CM T level of 1.5V. Both ICs are powered from the same 3V supply voltage. The inputs to the LTC6420-20 can be confi gured in various ways, as described in the Input Impedance and Matching section of this data sheet. The outputs of the LTC6420-20 R may be connected directly to the analog inputs of an ADC simple lowpass or bandpass fi ...
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... R5 C25 1% [2] 0.1μ ENB +OUTA OPT OCMA +INA –OUTA [ –INA – LTC6420-20 4 – –INB R10 C34 6 +INB –OUTB [2] 0.1μF 2 R11 – + ENA +OUTB OCMB OPT R12 ...
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... R5 49.9Ω 1/2 R6 LTC6420- 49.9Ω 12pF 10Ω 12pF 10Ω 49.9Ω C3 1/2 12pF R8 LTC6420-20 49.9Ω V –3dB FILTER BANDWIDTH = 120MHz OCM C6 2.2μF PIN 1 NOTCH R = 0.20 OR 0.25 0.75 ± 0.05 × 45° CHAMFER 1.50 REF R = 0.05 TYP 19 20 0.40 ± 0. 2.65 ± 0.10 2.50 REF 1.65 ± 0.10 (UDC20) QFN 1106 REV Ø 0.200 REF 0.25 ± ...
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... Dual ADC Driver for Wideband Direct-Conversion Receivers 3V C1 0.1μ 40.2Ω 10Ω 12pF – IN LTC6420-20 40.2Ω 10Ω C3 12pF –3dB FILTER BANDWIDTH = 140MHz COMMENTS A = 2V/V, OIP3 = 38dBm at 70MHz 4V/V, OIP3 = 40dBm at 70MHz 10V/V, OIP3 = 40dBm at 70MHz V 16-Bit SNR and SFDR at 1MHz, Rail-to-Rail Outputs OIP3 = 47dBm at 100MHz, Gain Control Range 10 ...