LTC2226 LINER [Linear Technology], LTC2226 Datasheet
LTC2226
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LTC2226 Summary of contents
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... A/D converters designed for digitizing high frequency, wide dynamic range signals. The LTC2228/LTC2227/LTC2226 are perfect for demand- ing imaging and communications applications with AC performance that includes 71.3dB SNR and 90dB SFDR for signals at the Nyquist frequency. ...
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... Digital Input Voltage ......................–0. Digital Output Voltage ................ –0.3V to (OV Power Dissipation .............................................1500mW Operating Temperature Range LTC2228C, LTC2227C, LTC2226C............. 0°C to 70°C LTC2228I, LTC2227I, LTC2226I ............ –40°C to 85°C Storage Temperature Range ................... –65°C to 125°C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL ...
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... MIN TYP MAX l ±0.5V to ± 1.5 1.9 l 0.5 1 – – – 0.2 80 575 LTC2227 LTC2226 MIN TYP MAX MIN TYP 71.4 71.4 70.2 71.2 70.1 71.3 71.1 70.9 70.7 70 MAX UNITS Bits 1 LSB 0.7 LSB 12 mV 2.5 %FS μV/°C ppm/° ...
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... OUT OUT I = –10μ –200μ 10μ 1.6mA –200μ 1.6mA –200μ 1.6mA O LTC2227 LTC2226 TYP MAX MIN TYP MAX 71.4 71.4 69.8 71.2 71.2 70.9 70.8 69.9 69 MIN TYP MAX 1.475 1.500 1.525 ± ...
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... This product can handle input currents of greater than 100mA below GND or above V Note 3V 65MHz (LTC2228), 40MHz (LTC2227 SAMPLE 25MHz (LTC2226), input range = 2V with differential drive, unless P-P otherwise noted. LTC2228/LTC2227/LTC2226 l The denotes the specifi cations which apply over the full operating temperature = 25° ...
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... LTC2228/LTC2227/LTC2226 TYPICAL PERFORMANCE CHARACTERISTICS LTC2228: Typical INL, 2V Range, 65Msps 1.00 0.75 0.50 0.25 0 –0.25 –0.50 –0.75 –1.00 0 1024 2048 3072 CODE 2228 G01 LTC2228: 8192 Point FFT 30MHz, –1dB, 2V Range, IN 65Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 ...
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... INPUT LEVEL (dBFS) LTC2228 Sample Rate, VDD 5mHz Sine Wave Input, –1dB RANGE 65 1V RANGE SAMPLE RATE (Msps) LTC2228/LTC2227/LTC2226 LTC2228: SNR and SFDR vs Sample Rate, 2V Range,f = 5MHz, –1dB IN 110 100 SFDR 90 80 SNR 70 60 200 ...
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... LTC2228/LTC2227/LTC2226 TYPICAL PERFORMANCE CHARACTERISTICS LTC2227: Typical INL, 2V Range, 40Msps 1.00 0.75 0.50 0.25 0 –0.25 –0.50 –0.75 –1.00 0 1024 2048 3072 4096 CODE 2227 G01 LTC2228: 8192 Point FFT 30MHz, –1dB, 2V Range, IN 40Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 ...
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... SFDR 50 REFERENCE LINE –60 –50 –40 –30 –20 –10 INPUT LEVEL (dBFS) 2227 G13 LTC2228/LTC2227/LTC2226 LTC2227: SNR and SFDR vs Sample Rate, 2V Range,f = 5MHz, –1dB IN 110 SFDR 100 90 80 SNR 200 SAMPLE RATE (Msps) ...
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... Range, IN 25Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 FREQUENCY (MHz) 2226 G06 LTC2226: SNR vs Input Frequency, –1dB, 2V Range, 25Msps 100 150 0 50 200 INPUT FREQUENCY (MHz) 2226 G09 222876fb ...
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... SFDR 50 REFERENCE LINE –10 –60 –50 –40 –30 –20 INPUT LEVEL (dBFS) 2226 G13 LTC2228/LTC2227/LTC2226 LTC2226: SNR and SFDR vs Sample Rate, 2V Range,f = 5MHz, –1dB IN 110 SFDR 100 90 80 SNR 70 60 200 SAMPLE RATE (Msps) LTC2226: I ...
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... LTC2228/LTC2227/LTC2226 PIN FUNCTIONS + A (Pin 1): Positive Differential Analog Input. IN – A (Pin 2): Negative Differential Analog Input. IN REFH (Pins 3, 4): ADC High Reference. Short together and bypass to Pins 5, 6 with a 0.1μF ceramic chip capacitor as close to the pin as possible. Also bypass to Pins 5, 6 with an additional 2.2μF ceramic chip capacitor and to ground with a 1μ ...
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... INPUT FIRST PIPELINED S/H ADC STAGE – 1.5V REFERENCE 2.2μF RANGE SELECT REF SENSE BUF LTC2228/LTC2227/LTC2226 SECOND PIPELINED THIRD PIPELINED FOURTH PIPELINED ADC STAGE ADC STAGE ADC STAGE REFH REFL INTERNAL CLOCK SIGNALS CLOCK/DUTY DIFF REF CYCLE CONTROL AMP REFH 0.1μF ...
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... LTC2228/LTC2227/LTC2226 TIMING DIAGRAM t AP ANALOG N INPUT t H CLK – 5 D0-D11 Timing Diagram – – – – 222876 TD01 222876fb ...
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... THD. IMD is the change in one sinusoidal input caused by the presence of another sinusoidal input at a different frequency. LTC2228/LTC2227/LTC2226 If two pure sine waves of frequencies fa and fb are ap- plied to the ADC input, nonlinearities in the ADC transfer function can create distortion products at the sum and difference frequencies of mfa ± ...
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... LTC2228/LTC2227/LTC2226 APPLICATIONS INFORMATION CONVERTER OPERATION As shown in Figure 1, the LTC2228/LTC2227/LTC2226 is a CMOS pipelined multi-step converter. The converter has six pipelined ADC stages; a sampled analog input will result in a digitized value fi ve cycles later (see the Timing Diagram section). For optimal AC performance the analog inputs should be driven differentially ...
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... ADC with a 2.2μF or greater capacitor. Input Drive Impedance As with all high performance, high speed ADCs, the dy- namic performance of the LTC2228/LTC2227/LTC2226 can be infl uenced by the input drive circuitry, particularly the second and third harmonics. Source impedance and input reactance can infl uence SFDR. At the falling edge of CLK, the sample-and-hold circuit will connect the 4pF sampling capacitor to the input pin and start the sampling period ...
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... LTC2228/LTC2227/LTC2226 APPLICATIONS INFORMATION 2.2μF HIGH SPEED DIFFERENTIAL 25Ω AMPLIFIER ANALOG + + INPUT CM 12pF – – 25Ω Figure 4. Differential Drive with an Amplifi er Figure 5 shows a single-ended input circuit. The impedance seen by the analog inputs should be matched. This circuit is not recommended if low distortion is required. ...
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... TYPICAL APPLICATIONS Reference Operation Figure 9 shows the LTC2228/LTC2227/LTC2226 refer- ence circuitry consisting of a 1.5V bandgap reference, a difference amplifi er and switching and control circuit. The internal voltage reference can be confi gured for two pin selectable input ranges of 2V (±1V differential (± ...
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... TTL level signal. A sinusoidal clock can also be used along with a low jitter squaring circuit before the CLK pin (Figure 11). The noise performance of the LTC2228/LTC2227/LTC2226 can depend on the clock signal quality as much as on the analog input. Any noise present on the clock signal will result in additional aperture jitter that will be RMS summed with the inherent ADC aperture jitter ...
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... Maximum and Minimum Conversion Rates The maximum conversion rate for the LTC2228/LTC2227/ LTC2226 is 65Msps (LTC2228), 40Msps (LTC2227), and 25Msps (LTC2226). For the ADC to operate properly, the CLK signal should have a 50% (±5%) duty cycle. Each half cycle must have at least 7.3ns (LTC2228), 11.8ns (LTC2227), and 18 ...
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... Hi-Z state Grounding and Bypassing Off The LTC2228/LTC2227/LTC2226 require a printed circuit board with a clean, unbroken ground plane. A multilayer board with an internal ground plane is recommended. Layout for the printed circuit board should ensure that digital and analog signal lines are separated as much as possible ...
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... Heat Transfer Most of the heat generated by the LTC2228/LTC2227/ LTC2226 is transferred from the die through the bottom- side Exposed Pad and package leads onto the printed circuit board. For good electrical and thermal performance, the exposed pad should be soldered to a large grounded pad on the PC board critical that all ground pins are connected to a ground plane of suffi ...
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... LTC2228/LTC2227/LTC2226 APPLICATIONS INFORMATION 24 222876fb ...
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... APPLICATIONS INFORMATION Silkscreen Top LTC2228/LTC2227/LTC2226 Inner Layer 2 GND Topside 222876fb 25 ...
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... LTC2228/LTC2227/LTC2226 APPLICATIONS INFORMATION Inner Layer 3 Power 26 Bottomside Silkscreen Bottom 222876fb ...
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... Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC2228/LTC2227/LTC2226 UH Package 32-Lead Plastic QFN (5mm × 5mm) (Reference LTC DWG # 05-08-1693 Rev D) 0 ...
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... ADC, LVDS Outputs LTC2220-1 12-Bit, 185Msps, 3V ADC, LVDS Outputs LTC2224 12-Bit, 135Msps, 3V ADC, High IF Sampling LTC2225 12-Bit, 10Msps, 3V ADC, Lowest Power LTC2226 12-Bit, 25Msps, 3V ADC, Lowest Power LTC2227 12-Bit, 40Msps, 3V ADC, Lowest Power LTC2228 12-Bit, 65Msps, 3V ADC, Lowest Power LTC2229 ...