LTC6400-8 Linear Technology, LTC6400-8 Datasheet
LTC6400-8
Related parts for LTC6400-8
LTC6400-8 Summary of contents
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... ADCs with low noise and low distortion, but can also be used as a general-purpose broadband gain block. The LTC6400-8 is easy to use, with minimal support cir- cuitry 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 ca- pacitors in many applications. The gain is internally fi ...
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... PART NUMBER LTC6401-8 LTC6401-14 LTC6401-20 LTC6401-26 LTC6400-8 LTC6400-14 LTC6400-20 LTC6400-26 In addition to the LTC6400 family of amplifi ers, a lower power LTC6401 family is available. The LTC6401 is pin compatible to the LTC6400, and has the same low noise performance. The lower power consumption of the LTC6401 comes at the expense of slightly higher non-linearity, especially at input frequencies above 140MHz ...
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... Differential Differential Differential, Includes Parasitic Input Common Mode Voltage 1.1V~1. 1.6V OCM V = 1.1V to 1.5V OCM ENABLE = 0.8V ENABLE = 2.4V ENABLE = 0.8V, Input and Output Floating ENABLE = 2.4V, Input and Output Floating + V = 2.85V to 3.5V LTC6400-8 = 1.25V, ENABLE = 0V unless L MIN TYP MAX UNITS l 7 –0.13 mdB/° ...
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... LTC6400-8 www.DataSheet4U.com AC ELECTRICAL CHARACTERISTICS ENABLE = 0V unless otherwise noted. L SYMBOL PARAMETER –3dBBW –3dB Bandwidth 0.5dBBW Bandwidth for 0.5dB Flatness 0.1dBBW Bandwidth for 0.1dB Flatness 1/f 1/f Noise Corner SR Slew Rate t 1% Settling Time S1% t Overdrive Recovery Time OVDR t Turn-On Time ON t Turn-Off Time OFF – ...
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... Note 5: Input and output baluns used. See Test Circuit A. Note 6: Measured using Test Circuit B. R Note 7: Since the LTC6400 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 LTC6400-8 with amplifi ...
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... LTC6400-8 www.DataSheet4U.com TYPICAL PERFORMANCE CHARACTERISTICS Frequency Response 14 TEST CIRCUIT –2 –4 10 100 1000 FREQUENCY (MHz) Input and Output Refl ection and Reverse Isolation vs Frequency 0 TEST CIRCUIT B –10 S11 –20 –30 –40 S22 –50 S12 –60 –70 –80 ...
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... Intercept Point vs Frequency 200Ω DIFFERENTIAL INPUT (NOTE 100 150 200 300 FREQUENCY (MHz) 64008 G16 LTC6400-8 Harmonic Distortion vs Frequency –40 DIFFERENTIAL INPUT OUT P-P –50 –60 –70 –80 –90 –100 –110 100 150 ...
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... LTC6400-8 www.DataSheet4U.com TYPICAL PERFORMANCE CHARACTERISTICS Turn-On Time 3.5 3.0 2.5 2.0 1.5 1.0 0 87.5Ω PER OUTPUT L –0.5 – TIME (ns) PIN FUNCTIONS + V (Pins 1, 3, 10): Positive Power Supply (Normally tied 3.3V). All three pins must be tied to the same voltage. Bypass each pin with 1000pF and 0.1μF capacitors as close to the pins as possible ...
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... OCM The LTC6400-8 is very fl exible in terms of I/O coupling. It can be AC- or DC-coupled at the inputs, the outputs or both. Due to the internal connection between input and output, users are advised to keep input common mode voltage between 1V and 1.8V for proper operation. If the inputs are AC-coupled, the input common mode voltage is automatically biased approximately 450mV above V and thus no external circuitry is needed for bias ...
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... Using a Balun order to minimize the refl ection due to input mismatch. Alternatively, one could apply a narrowband impedance match at the inputs of the LTC6400-8 for frequency selec- tion and/or noise reduction. Referring to Figure 3, LTC6400-8 can be easily confi gured for single-ended input and differential output without a balun ...
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... Figure 5. LTC6400-8 Internal Filter Topology Modifi ed for Low Filter Bandwidth (Three External Capacitors) only a few components as shown in Figure 6. Three 39pF capacitors and a 16nH inductor create a bandpass fi lter with 165MHz center frequency, –3dB frequencies at 138MHz and 200MHz ...
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... FREQUENCY (MHz) Figure 8. IMD3 for the Combination of LTC6400-8 and LTC2208 Test Circuits Due to the fully-differential design of the LTC6400 and its usefulness in applications with differing characteristic specifi cations, two test circuits are used to generate the information in this datasheet. Test Circuit A is DC987B, a two-port demonstration circuit for the LTC6400 family ...
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... R19 1.5k R20 C7 0.1μF 1k C23 C5 C19 0.1μF 0.1μF 0.1μF R21 (1) C24 C6 0.1μF 0.1μF (2) VERSION LTC6400CUD-8 200Ω MINI-CIRCUITS TCM4-19 (1: SIGNAL LEVEL LTC6400-8 C17 C18 1000pF 0.1μF 9 R10 86.6Ω TCM 4:19 3 (1) 0.1μF 7 1:4 2 SL2 R7 (2) ( 0.1μF 86.6Ω ...
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... LTC6400-8 www.DataSheet4U.com TYPICAL APPLICATIONS PORT 1 (50Ω) 1/2 AGILENT 133Ω E5O71A PORT 2 (50Ω) 14 Test Circuit B, 4-Port Analysis + V 1000pF 0.1μF V – ENABLE + BIAS CONTROL OUT +IN 500Ω 200Ω 12.5Ω 0.1μF FILT 50Ω +IN IN+ OUT– ...
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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) PIN 1 TOP MARK (NOTE 6) 1.45 0.10 (4-SIDES) 0.200 REF 0.00 – 0.05 LTC6400-8 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 64008f 15 ...
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... LTC6400-8 www.DataSheet4U.com RELATED PARTS PART NUMBER DESCRIPTION High-Speed Differential Amplifi ers/Differential Op Amps ® LT 1993-2 800MHz Differential Amplifi er/ADC Driver LT1993-4 900MHz Differential Amplifi er/ADC Driver LT1993-10 700MHz Differential Amplifi er/ADC Driver LT1994 Low Noise, Low Distortion Differential Op Amp LT5514 Ultralow Distortion IF Amplifi ...