LTC2245 Linear Technology, LTC2245 Datasheet
LTC2245
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LTC2245 Summary of contents
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... CONTROL CLK DESCRIPTIO The LTC converter designed for digitizing high frequency, wide dynamic range signals. The LTC2245 is perfect for de- manding imaging and communications applications with AC performance that includes 74.4dB SNR and 90dB SFDR for signals well beyond the Nyquist frequency. Range DC specs include ± ...
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... Analog Input Voltage (Note 3) ..... –0. Digital Input Voltage .................... –0. Digital Output Voltage ................ –0.3V to (OV Power Dissipation ............................................ 1500mW Operating Temperature Range LTC2245C ............................................... 0°C to 70°C LTC2245I .............................................–40°C to 85°C Storage Temperature Range ..................–65°C to 125° VERTER CHARACTERISTICS ...
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... Input 5MHz Input 70MHz Input 5MHz Input 70MHz Input 5MHz Input 70MHz Input f = 4.3MHz, f IN1 IN2 CONDITIONS OUT 2.7V < V < 3.4V DD –1mA < I < 1mA OUT LTC2245 MIN TYP ±0.5V to ±1V ● ● 1 1.5 ● 0.5 1.5 ● –1 DD ● –3 ● –3 0 0.2 80 ...
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... LTC2245 U U DIGITAL I PUTS A D DIGITAL OUTPUTS full operating temperature range, otherwise specifications are at T SYMBOL PARAMETER LOGIC INPUTS (CLK, OE, SHDN) www.datasheet4u.com V High Level Input Voltage IH V Low Level Input Voltage IL I Input Current IN C Input Capacitance IN LOGIC OUTPUTS Hi-Z Output Capacitance ...
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... DD with differential Note 9: Recommended operating conditions. P-P U Typical DNL, 2V Range 1.0 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 16384 0 4096 8192 12288 CODE 2245 G01 LTC2245 MIN TYP ● 1 ● ● ● ● ● 1.4 2.7 ● 4.3 ● 3 3V, f ...
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... LTC2245 W TYPICAL PERFOR A CE CHARACTERISTICS 8192 Point FFT 70.1MHz, IN www.datasheet4u.com –1dB, 2V Range 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 FREQUENCY (MHz) SNR vs Input Frequency, –1dB, 2V Range ...
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... V and turns the clock duty cycle stabilizer on. 2/3 V 2’s complement output format and turns the clock duty cycle stabilizer on. V format and turns the clock duty cycle stabilizer off. LTC2245 I vs Sample Rate, 5MHz Sine OVDD Wave Input, –1dB ...
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... LTC2245 CTIO S SENSE (Pin 30): Reference Programming Pin. Connecting selects the internal reference and a ±0.5V SENSE selects the internal reference and a ±1V input range. V www.datasheet4u.com DD input range. An external reference greater than 0.5V and less than 1V applied to SENSE selects an input range of ± ...
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... RMS value of a full scale input signal )/V1) Input Bandwidth The input bandwidth is that input frequency at which the amplitude of the reconstructed fundamental is reduced by 3dB for a full scale input signal. LTC2245 – – 2245 TD01 2245fa 9 ...
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... JITTER IN CONVERTER OPERATION As shown in Figure 1, the LTC2245 is a CMOS pipelined multistep converter. The converter has six pipelined ADC stages; a sampled analog input will result in a digitized value five cycles later (see the Timing Diagram section). For optimal AC performance the analog inputs should be driven differentially ...
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... Poor matching will result in higher even order harmonics, especially the second. Input Drive Circuits + IN Figure 3 shows the LTC2245 being driven – should be IN transformer with a center tapped secondary. The second- ary center tap is DC biased with V signal at its optimum DC level ...
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... A IN 2245 F05 Reference Operation Figure 6 shows the LTC2245 reference circuitry consisting of a 1.5V bandgap reference, a difference amplifier and switching and control circuit. The internal voltage refer- ence can be configured for two pin selectable input ranges of 2V (±1V differential (±0.5V differential). Tying the ...
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... Figure 7. 1.5V Range ADC W U The noise performance of the LTC2245 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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... Data Format 11 1111 1111 1110 Using the MODE pin, the LTC2245 parallel digital output 10 0000 0000 0001 10 0000 0000 0000 can be selected for offset binary or 2’s complement 10 0000 0000 0000 format. Connecting MODE to GND or 1/3V binary output format ...
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... Hi-Z state Grounding and Bypassing The LTC2245 requires a printed circuit board with a clean, unbroken ground plane. A multilayer board with an inter- , should be tied nal ground plane is recommended. Layout for the printed DD circuit board should ensure that digital and analog signal lines are separated as much as possible ...
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... LTC2245 U U APPLICATIO S I FOR ATIO 2245fa ...
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... U U APPLICATIO S I FOR ATIO Silkscreen Top www.datasheet4u.com W U Inner Layer 2 GND LTC2245 Topside 2245fa 17 ...
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... LTC2245 U U APPLICATIO S I FOR ATIO Inner Layer 3 Power www.datasheet4u.com Silkscreen Bottom Bottomside 2245fa ...
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... DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.20mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE LTC2245 BOTTOM VIEW—EXPOSED PAD 0.23 TYP R = 0.115 (4 SIDES) ...
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