LTC2205 Linear Technology, LTC2205 Datasheet
LTC2205
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LTC2205 Summary of contents
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... P-P Input Range) of the ADC can be optimized with the PGA front end. P-P The LTC2205/LTC2204 are perfect for demanding com- munications applications, with AC performance that in- cludes 79dB SNR and 100dB spurious free dynamic range (SFDR). Ultralow jitter of 90fs high input frequencies with excellent noise performance. ...
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... Analog Input Voltage (Note 3) ......–0. Digital Input Voltage .....................–0. Digital Output Voltage ................ –0.3V to (OV Power Dissipation .............................................2000mW Operating Temperature Range LTC2205C/LTC2204C ............................... 0°C to 70°C LTC2205I/LTC2204I .............................. –40°C to 85°C Storage Temperature Range .................. –65°C to 150°C Digital Output Supply Voltage (OV ORDER INFORMATION ...
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... Input (1.5V Range, PGA = 1) 140MHz Input (2.25V Range, PGA = 0) 140MHz Input (1.5V Range, PGA = 1) 170MHz Input (2.25V Range, PGA = 0) 170MHz Input (1.5V Range, PGA = 1) LTC2205/LTC2204 MIN TYP l 1 1.25 l –1 l –3 10 – 6.5 – 1.8 0 700 LTC2204 LTC2205 MIN TYP MAX MIN TYP 79.1 79.0 76.5 76.4 77.6 79.0 77.5 78.9 78 79.0 77.9 78.9 76.5 76.4 78.5 78.4 74.6 76.3 74.6 76 ...
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... Input (1.5V Range, PGA = 1) 70MHz Input (2.25V Range, PGA = 0) 70MHz Input (1.5V Range, PGA = 1) 140MHz Input (2.25V Range, PGA = 0) 140MHz Input (1.5V Range, PGA = 1) 170MHz Input (2.25V Range, PGA = 0) 170MHz Input (1.5V Range, PGA = 1) LTC2204 LTC2205 MIN TYP MAX MIN TYP 105 105 105 ...
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... 160µA 0. 1.6mA 0.10 O – –200µA 2. 1.60mA 0 –200µA 1. 1.60mA 0.1 O LTC2204 LTC2205 MIN TYP MAX MIN TYP 3.135 3.3 3.465 3.315 3.3 0.2 0.2 0.5V 3.6 0.5V 3.3 145 200 185 480 660 610 MAX UNITS 1.35 V ppm/°C mV/ V Ω MAX UNITS ...
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... Note 3: When these pin voltages are taken below GND or above V will be clamped by internal diodes. This product can handle input currents of greater than 100mA below GND or above V Note 3.3V 65MHz (LTC2205), 40MHz (LTC2204) DD SAMPLE + – differential ENC /ENC = 2V sine wave with 1 ...
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... IN PGA = 1, DITH = 0 0 –20 –40 –60 –80 –100 –120 –140 FREQUENCY (MHz) 22054 G04 LTC2205: 64K Point FFT 5.1MHz, –40dBFS, IN PGA = 0, DITH = 0 0 –20 –40 –60 –80 –100 –120 –140 FREQUENCY (MHz) ...
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... IN PGA = 0, DITH = 0 0 –20 –40 –60 –80 –100 –120 –140 FREQUENCY (MHz) 22054 G13 LTC2205: 64K Point FFT, 65Msps 70.1MHz, –1dBFS, IN PGA = 1, DITH = 0 0 –20 –40 –60 –80 –100 –120 –140 FREQUENCY (MHz) ...
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... IN –40dBFS, PGA = 0, DITH = 0 0 –20 –40 –60 –80 –100 –120 –140 FREQUENCY (MHz) 22054 G25 LTC2205/LTC2204 LTC2205: 64K Point FFT, 65Msps 70.1MHz, –40dBFS, IN PGA = 0, DITH = 1 0 –20 –40 –60 –80 –100 –120 –140 FREQUENCY (MHz) ...
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... IN1 f = 20.1MHz, –7dBFS, PGA = 0 IN2 0 –20 –40 –60 –80 –100 –120 –140 FREQUENCY (MHz) 22054 G28 LTC2205: SFDR vs Input Level 15.1MHz, IN DITH = 0, RAND = 1, PGA = 0 130 120 110 100 –80 –60 –50 –40 –30 0 – ...
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... G37 LTC2205: SFDR and SNR vs Supply Voltage 5.1MHz, IN 65Msps, PGA = 0 110 SFDR 100 90 80 SNR 70 2.4 2.6 2.8 3.0 3.2 110 SUPPLY VOLTAGE 22054 G40 LTC2205: Gain Drift with External Reference vs Temperature 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 –1.2 80 100 –60 –40 – TEMPERATURE (°C) ...
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... LTC2204: 64K Point FFT, 40Msps 5.1MHz, –40dBFS, IN PGA = 0, DITH = 0 0 –20 –40 –60 –80 –100 –120 –140 FREQUENCY (MHz) 12 LTC2205: SFDR and SNR vs Input Common Mode Voltage 5.1MHz IN 110 SFDR 100 90 80 SNR 70 80 0.50 0.75 1.00 1.25 1.50 INPUT COMMON MODE VOLTAGE (V) 22054 G46 ...
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... LTC2204: 64K Point FFT, 40Msps 70.1MHz, –25dBFS, IN PGA = 0, DITH = 0 0 –20 –40 –60 –80 –100 –120 –140 FREQUENCY (MHz) 22054 G60 LTC2205/LTC2204 LTC2204: 64K Point FFT, 40Msps 15.1MHz, –25dBFS, IN PGA = 0, DITH = 1 0 –20 –40 –60 –80 –100 –120 –140 ...
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... LTC2205/LTC2204 TYPICAL PERFORMANCE CHARACTERISTICS LTC2204: 64K Point FFT, 40Msps 70.1MHz, –40dBFS, IN PGA = 0, DITH = 0 www.datasheet4u.com 0 –20 –40 –60 –80 –100 –120 –140 FREQUENCY (MHz) LTC2204: 64K Point FFT, 40Msps 140.1MHz, –1dBFS, IN PGA = 1, DITH = 0 0 –20 –40 –60 –80 –100 –120 – ...
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... DITH = 0, RAND = 1 130 120 110 100 –80 –60 –50 –40 –30 –70 INPUT LEVEL (dBFS) 22054 G78 LTC2205/LTC2204 LTC2204: SFDR vs Input Level 5.1MHz, DITH = 1, RAND = 1 IN 130 120 110 100 –20 –10 0 –80 –70 – ...
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... LTC2205/LTC2204 TYPICAL PERFORMANCE CHARACTERISTICS LTC2204: SFDR vs Input Frequency, DITH = 0, RAND = 0 www.datasheet4u.com 110 100 90 PGA = 1 80 PGA = 100 150 200 INPUT FREQUENCY (MHz) LTC2204: SFDR and SNR vs Supply Voltage, DITH = 0, RAND = 0 110 SFDR 100 90 80 SNR 70 2.4 2.6 2.8 3.0 3.2 3.4 SUPPLY VOLTAGE (V) 16 LTC2204: SNR vs Input Frequency, ...
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... PGA (Pin 47): Programmable Gain Amplifi er Control Pin. Low selects a front-end gain of 1, input range of 2.25V selects a front-end gain of 1.5, input range of 1.5V GND (Exposed Pad, Pin 49): ADC Power Ground. The ex- posed pad on the bottom of the package must be soldered to ground. LTC2205/LTC2204 – (Pin 29): Data Valid Output. CLKOUT – (Pin 30): Inverted Data Valid Output ...
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... LTC2205/LTC2204 BLOCK DIAGRAM + A IN www.datasheet4u.com INPUT FIRST PIPELINED S/H ADC STAGE – DITHER SIGNAL GENERATOR RANGE SELECT SENSE V CM BUFFER VOLTAGE REFERENCE 18 SECOND PIPELINED THIRD PIPELINED ADC STAGE ADC STAGE ADC CLOCKS DIFFERENTIAL ADC INPUT PGA REFERENCE LOW JITTER CLOCK DRIVER + – ...
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... Aperture Delay Jitter The variation in the aperture delay time from conversion to conversion. This random variation will result in noise when sampling an AC input. The signal to noise ratio due to the jitter alone will be: SNR JITTER LTC2205/LTC2204 + – equals the ENC π = –20log (2 • f • ...
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... The encode input is also differential for improved common mode noise immunity. The LTC2205/LTC2204 have two phases of operation, determined by the state of the differential ENC put pins. For brevity, the text will refer to ENC – ...
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... CM tolerated—this will help suppress random noise as well as noise coupled from the digital circuitry. The LTC2205/ LTC2204 do not require any input fi lter to achieve data sheet specifi cations; however, no fi ltering will put more stringent noise requirements on the input drive circuitry. ...
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... LTC2205/LTC2204 APPLICATIONS INFORMATION Transformer Coupled Circuits Figure 3 shows the LTC2205/LTC2204 being driven by www.datasheet4u.com an RF transformer with a center-tapped secondary. The secondary center tap is DC biased with V ADC input signal at its optimum DC level. Figure 3 shows a 1:1 turns ratio transformer. Other turns ratios can be used; however, as the turns ratio increases so does the impedance seen by the ADC. Source impedance greater than 50Ω ...
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... Reference Operation Figure 6 shows the LTC2205/LTC2204 reference circuitry consisting of a 2.5V bandgap reference, a programmable gain amplifi er and control circuit. The LTC2205/LTC2204 have three modes of reference operation: Internal Refer- ence, 1.25V external reference or 2.5V external reference. To use the internal reference, tie the SENSE pin to V use an external reference, simply apply either a 1 ...
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... See the typical performance curves section. Driving the Encode Inputs The noise performance of the LTC2205/LTC2204 can depend on the encode signal quality as much as on the analog input. The encode inputs are intended to be driven differentially, primarily for noise immunity from common mode noise sources ...
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... Figure 9. Single-Ended ENC Drive, Not Recommended for Low Jitter Maximum and Minimum Encode Rates The maximum encode rate for the LTC2205 is 65Msps. The maximum encode rate for the LTC2204 is 40Msps. For the ADC to operate properly the encode signal should have a 50% (±2.5%) duty cycle. Achieving a precise 50% ...
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... As with all high speed/high resolution converters, the digi- tal output loading can affect the performance. The digital outputs of the LTC2205/LTC2204 should drive a minimum capacitive load to avoid possible interaction between the digital outputs and sensitive input circuitry. The output should be buffered with a device such as a ALVCH16373 CMOS latch ...
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... LSB and all other bits. The LSB, OF and CLKOUT output are not affected. The output Randomizer function is active when the RAND pin is high. LTC2205/LTC2204 CLKOUT OF D15 D14 D2 D1 RAND SCRAMBLE ENABLED D0 LTC2205/LTC2204 CLKOUT OF D15/D0 D14/D0 • • • D2/D0 D1/D0 D0 22054 F12 22054fb 27 ...
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... OV outputs will swing between OGND and OV Internal Dither The LTC2205/LTC2204 are 16-bit ADCs with very linear transfer functions; however, at low input levels even slight imperfections in the transfer function will result in unwanted tones. Small errors in the transfer function are 28 usually a result of ADC element mismatches ...
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... Heat Transfer Most of the heat generated by the LTC2205/LTC2204 is transferred from the die through the bottom-side exposed pad. For good electrical and thermal performance, the exposed pad must be soldered to a large grounded pad on the PC board critical that the exposed pad and all ground pins are connected to a ground plane of suffi ...
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... DC918C-D LTC2206CUK DC918C-E LTC2205CUK DC918C-F LTC2205CUK DC918C-G LTC2204CUK DC918C-H LTC2207CUK-14 DC918C-I LTC2207CUK-14 DC918C-J LTC2206CUK-14 DC918C-K LTC2206CUK-14 DC918C-L LTC2205CUK-14 See Web site for ordering details or contact local sales. 30 3.3V NOT PROVIDED 0V BY DC718 CLOCK POLARITY ) DITHER SHUTDOWN RESOLUTION 16-Bit 105Msps 16-Bit 105Msps 16-Bit ...
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... APPLICATIONS INFORMATION www.datasheet4u.com LTC2205/LTC2204 Silkscreen Top Top Side 22054fb 31 ...
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... LTC2205/LTC2204 APPLICATIONS INFORMATION www.datasheet4u.com Inner Layer 2 Inner Layer 4 32 Inner Layer 3 Inner Layer 5 22054fb ...
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... APPLICATIONS INFORMATION www.datasheet4u.com LTC2205/LTC2204 Bottom Side Silkscreen Bottom 22054fb 33 ...
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... LTC2205/LTC2204 APPLICATIONS INFORMATION www.datasheet4u.com OGND OGND 38 23 D12 D13 D14 D15 DITH 44 17 MODE SHDN 45 16 RAND GND PGA GND 22054fb ...
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... Plastic QFN (7mm × 7mm) (Reference LTC DWG # 05-08-1704) 0.70 ±0.05 5.50 REF 6.10 ±0.05 7.50 ±0.05 (4 SIDES) PACKAGE OUTLINE 0.25 ±0.05 0.50 BSC 0.75 ± 0. 0.10 TYP 5.50 REF (4-SIDES) 0.200 REF 0.00 – 0.05 LTC2205/LTC2204 R = 0.115 TYP 47 48 PIN 1 CHAMFER C = 0.35 5.15 ± 0.10 5.15 ± 0.10 (UK48) QFN 0406 REV C 0.25 ± 0.05 0.50 BSC BOTTOM VIEW—EXPOSED PAD 0.40 ± 0.10 1 ...
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... Low Noise, Low Distortion Fully Differential Input/ Output Amplifi er/Driver LTC2202 16-Bit, 10Msps, 3.3V ADC, Lowest Noise LTC2203 16-Bit, 25Msps, 3.3V ADC, Lowest Noise LTC2204 16-Bit, 40Msps, 3.3V ADC LTC2205 16-Bit, 65Msps, 3.3V ADC LTC2206 16-Bit, 80Msps, 3.3V ADC LTC2207 16-Bit, 105Msps, 3.3V ADC LTC2208 16-Bit, 130Msps, 3.3V ADC, LVDS Outputs LTC2220-1 12-Bit, 185Msps, 3 ...