LTC2297 LINER [Linear Technology], LTC2297 Datasheet
LTC2297
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LTC2297 Summary of contents
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... A/D converters de- signed for digitizing high frequency, wide dynamic range signals. The LTC2298/LTC2297/LTC2296 are perfect for demanding imaging and communications applications with AC performance that includes 74dB SNR and 85dB SFDR for signals well beyond the Nyquist frequency. ...
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... Digital Input Voltage .................... –0. Digital Output Voltage ................ –0.3V to (OV Power Dissipation ............................................ 1500mW Operating Temperature Range LTC2298C, LTC2297C, LTC2296C ........... 0°C to 70°C LTC2298I, LTC2297I, LTC2296I ..........–40°C to 85°C Storage Temperature Range ..................–65°C to 125°C Lead Temperature (Soldering, 10 sec).................. 300°C ...
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... MIN TYP MAX ● ● 1 1.5 1.9 ● –1 ● –3 ● –3 0 0.2 80 575 LTC2297 LTC2296 MIN TYP MAX MIN TYP MAX 74.4 74.5 72.7 74.2 72.4 74.4 73.9 73.4 73 ...
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... LTC2298/LTC2297/LTC2296 TER AL REFERE CE CHARACTERISTICS PARAMETER V Output Voltage CM V Output Tempco CM V Line Regulation CM V Output Resistance DIGITAL I PUTS A D DIGITAL OUTPUTS full operating temperature range, otherwise specifications are at T SYMBOL PARAMETER LOGIC INPUTS (CLK, OE, SHDN, MUX) V High Level Input Voltage ...
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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 3V 65MHz (LTC2298), 40MHz (LTC2297 SAMPLE 25MHz (LTC2296), input range = 2V with differential drive, unless P-P otherwise noted ...
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... LTC2298/LTC2297/LTC2296 W U TYPICAL PERFOR A CE CHARACTERISTICS LTC2298/LTC2297/LTC2296: Crosstalk vs Input Frequency –100 –105 –110 –115 –120 –125 –130 100 INPUT FREQUENCY (MHz) 229876 G01 LTC2298: 8192 Point FFT 5MHz, –1dB, 2V Range, IN 65Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 – ...
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... VDD 5MHz Sine Wave Input, –1dB 155 145 135 125 2V RANGE 115 105 SAMPLE RATE (Msps) LTC2298/LTC2297/LTC2296 LTC2298: SFDR vs Input Frequency, –1dB, 2V Range, 65Msps 100 100 0 150 INPUT FREQUENCY (MHz) LTC2298: SNR vs Input Level, ...
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... FREQUENCY (MHz) 2297 G04 LTC2297: 8192 Point 2-Tone FFT 21.6MHz and 23.6MHz, IN –1dB, 2V Range, 40Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 0 ...
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... SAMPLE RATE (Msps) LTC2296: Typical DNL, 2V Range, 25Msps 1.00 0.75 0.50 0.25 0 –0.25 –0.50 –0.75 –1.00 0 4096 8192 12288 CODE LTC2297: SNR vs Input Level 5MHz, 2V Range, 40Msps IN 80 dBFS dBc –60 –50 –40 –30 –20 INPUT LEVEL (dBFS) 2297 G11 ...
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... LTC2298/LTC2297/LTC2296 W U TYPICAL PERFOR A CE CHARACTERISTICS LTC2296: 8192 Point FFT 30MHz, –1dB, 2V Range, IN 25Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 FREQUENCY (MHz) 2296 G04 LTC2296: 8192 Point 2-Tone FFT 10.9MHz and 13.8MHz, IN – ...
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... CLKB (Pin 9): Channel B Clock Input. The input sample starts on the positive edge. REFLB (Pins 11, 12): Channel B Low Reference. Short together and bypass to Pins 13, 14 with a 0.1µF ceramic LTC2298/LTC2297/LTC2296 LTC2296 Sample Rate, VDD 5MHz Sine Wave Input, –1dB ...
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... LTC2298/LTC2297/LTC2296 CTIO S MUX (Pin 21): Digital Output Multiplexer Control. If MUX is High, Channel A comes out on DA0-DA13, OFA; Channel B comes out on DB0-DB13, OFB. If MUX is Low, the output busses are swapped and Channel A comes out on DB0- DB13, OFB; Channel B comes out on DA0-DA13, OFA. To multiplex both channels onto a single output bus, connect MUX, CLKA and CLKB together ...
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... ADC STAGE – 1.5V CM REFERENCE 2.2µF RANGE SELECT REF BUF SENSE Figure 1. Functional Block Diagram (Only One Channel is Shown) LTC2298/LTC2297/LTC2296 W SECOND PIPELINED THIRD PIPELINED FOURTH PIPELINED ADC STAGE ADC STAGE ADC STAGE REFH REFL INTERNAL CLOCK SIGNALS CLOCK/DUTY DIFF CYCLE REF ...
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... LTC2298/LTC2297/LTC2296 DIAGRA ANALOG N INPUT t H CLK – 6 D0-D13, OF ANALOG A INPUT A ANALOG B INPUT B t CLKA = CLKB = MUX A – 6 D0A-D13A, OFA D0B-D13B, OFB B – Dual Digital Output Bus Timing (Only One Channel is Shown – – ...
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... CONVERTER OPERATION As shown in Figure 1, the LTC2298/LTC2297/LTC2296 are dual CMOS pipelined multistep converters. The convert- ers have six pipelined ADC stages; a sampled analog input will result in a digitized value six cycles later (see the Timing Diagram section) ...
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... APPLICATIO S I FOR ATIO sensitive applications, the analog inputs can be driven single-ended with slightly worse harmonic distortion. The CLK input is single-ended. The LTC2298/LTC2297/ LTC2296 have two phases of operation, determined by the state of the CLK input pin. Each pipelined stage shown in Figure 1 contains an ADC, a reconstruction DAC and an interstage residue amplifier ...
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... Poor matching will result in higher even order harmonics, especially the second. Input Drive Circuits Figure 3 shows the LTC2298/LTC2297/LTC2296 being driven transformer with a center tapped second- ary. The secondary center tap is DC biased with V setting the ADC input signal at its optimum DC level. ...
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... ARE 0402 PACKAGE SIZE V CM 2.2µF 0.1µF 6.8nH + A IN 0.1µF 25Ω T1 0.1µF 25Ω 6.8nH – MA/COM, ETC 1-1-13 RESISTORS, CAPACITORS, INDUCTORS ARE 0402 PACKAGE SIZE LTC2298 LTC2297 LTC2296 229876 F06 LTC2298 LTC2297 LTC2296 229876 F07 LTC2298 LTC2297 LTC2296 229876 F08 229876f ...
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... U U APPLICATIO S I FOR ATIO Reference Operation Figure 9 shows the LTC2298/LTC2297/LTC2296 refer- ence circuitry consisting of a 1.5V bandgap reference, a difference amplifier and switching and control circuit. The internal voltage reference can be configured for two pin selectable input ranges of 2V (±1V differential (± ...
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... 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 (LTC2298), 11.8ns (LTC2297), and 18.9ns (LTC2296) for the ADC internal circuitry to have enough settling time for proper operation. 20 ...
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... DD from the digital outputs. Data Format Using the MODE pin, the LTC2298/LTC2297/LTC2296 parallel digital output can be selected for offset binary or 2’s complement format. Note that MODE controls both Channel A and Channel B. Connecting MODE to GND or 1/3V selects straight binary output format ...
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... Heat Transfer Most of the heat generated by the LTC2298/LTC2297/ LTC2296 is transferred from the die through the bottom- side exposed pad and package leads onto the printed circuit board. For good electrical and thermal perfor- mance, the exposed pad should be soldered to a large grounded pad on the PC board ...
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... U U APPLICATIO S I FOR ATIO LTC2298/LTC2297/LTC2296 W U 229876f 23 ...
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... LTC2298/LTC2297/LTC2296 U U APPLICATIO S I FOR ATIO Silkscreen Top Top Side 229876f ...
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... U U APPLICATIO S I FOR ATIO LTC2298/LTC2297/LTC2296 W U Inner Layer 2 GND Inner Layer 3 Power 229876f 25 ...
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... LTC2298/LTC2297/LTC2296 U U APPLICATIO S I FOR ATIO Bottom Side 229876f ...
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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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC2298/LTC2297/LTC2296 U UP Package 64-Lead Plastic QFN (9mm × 9mm) (Reference LTC DWG # 05-08-1705) 0.70 ± ...
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... LTC2298/LTC2297/LTC2296 RELATED PARTS PART NUMBER DESCRIPTION LTC1741 12-Bit, 65Msps ADC LTC1742 14-Bit, 65Msps ADC LTC1743 12-Bit, 50Msps ADC LTC1744 14-Bit, 50Msps ADC LTC1745 12-Bit, 25Msps ADC LTC1746 14-Bit, 25Msps ADC LTC1747 12-Bit, 80Msps ADC LTC1748 14-Bit, 80Msps ADC LTC1749 12-Bit, 80Msps Wideband ADC ...