LTC2173-14 Linear Technology Corporation, LTC2173-14 Datasheet
LTC2173-14
Related parts for LTC2173-14
LTC2173-14 Summary of contents
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... S/H ADC CORE INPUT ENCODE PLL INPUT GND Electrical Specifications Subject to Change LTC2174-14/LTC2173-14 14-Bit, 125Msps/105Msps/ 80Msps Low Power Quad ADCs DESCRIPTION ® The LTC 2175-14/2174-14/2173-14 are 4-channel, simul- taneous sampling 14-bit A/D converters designed for digitizing high frequency, wide dynamic range signals. ...
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... LTC2175-14/ LTC2174-14/LTC2173-14 www.DataSheet4U.com ABSOLUTE MAXIMUM RATINGS (Notes 1, 2) Supply Voltages ................................................ –0. Analog Input Voltage ( PAR/SER, SENSE) (Note 3) ...........–0. Digital Input Voltage (ENC , ENC SDI, SCK) (Note 4) .................................... –0.3V to 3.9V SDO (Note 4) ............................................ –0.3V to 3.9V Digital Output Voltage ................ –0.3V to (OV Operating Temperature Range LTC2175C, 2174C, 2173C ........................ 0° ...
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... Per Pin, 125Msps Per Pin, 105Msps Per Pin, 80Msps + – 0 < < < PAR/SER < 0.625 < SENSE < 1.3V Figure 6 Test Circuit LTC2175-14/ LTC2174-14/LTC2173-14 LTC2174-14 LTC2173-14 MAX MIN TYP MAX MIN TYP 14 14 3.75 –3.75 ±1 3.75 –3.5 ±1 0.9 –0.9 ±0.3 0.9 –0.9 ± ...
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... Input 73 l 70MHz Input 70.2 72.6 140MHz Input 72 10MHz Input (Note 12) –90 10MHz Input (Note 12) –105 = 25° MIN = 0 0.5 • < 1mA OUT = 0 1.225 < 1mA OUT < 1.9V DD LTC2174-14 LTC2173-14 MAX MIN TYP MAX MIN TYP 73.4 73.1 71.3 73.2 70.9 72.9 72.7 72 ...
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... OUT DIGITAL DATA OUTPUTS V Differential Output Voltage OD V Common Mode Output Voltage OS R On-Chip Termination Resistance TERM LTC2174-14/LTC2173-14 The l denotes the specifi cations which apply over the full operating = 25°C. (Note 5) A CONDITIONS (Note 8) Internally Set Externally Set (Note 8) + – ...
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... TYP 1.9 1.7 1.8 1.9 1.7 1.8 1.9 1.7 1.8 1.9 1.7 1.8 TBD 224 TBD 184 TBD 26 TBD 25 TBD 48 TBD 47 TBD 450 TBD 376 TBD 490 TBD 416 LTC2174-14 LTC2173-14 MIN TYP MAX MIN TYP 5 105 5 4.52 4.76 100 5.93 6.25 2 4.76 100 2 6.25 4.52 4.76 100 5.93 6.25 2 4.76 100 2 6. MIN TYP MAX 1/(8 • 1/(7 • 1/(6 • f ...
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... Note 11: The maximum sampling frequency depends on the speed grade of the part and also which serialization mode is used. The maximum serial + / data rate is 1000Mbps so t with differential drive, unless P-P Note 12: Near-channel crosstalk refers to Ch Ch.2, and Ch.3 to Ch.4. Far-channel crosstalk refers to Ch.1 to Ch.3, Ch.1 to Ch.4, Ch.2 to Ch.3, and Ch.2 to Ch.4. LTC2175-14/ LTC2174-14/LTC2173-14 MIN TYP 250 ...
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... LTC2175-14/ LTC2174-14/LTC2173-14 www.DataSheet4U.com TIMING DIAGRAMS ANALOG OUT#A OUT#A OUT#B OUT#B *SEE THE DIGITAL OUTPUTS SECTION ANALOG INPUT – ENC + ENC – DCO + DCO – – OUT OUT#A – OUT OUT#B SAMPLE N-6 NOTE THAT IN THIS MODE FR 8 2-Lane Output Mode, 16-Bit Serialization* ...
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... SAMPLE N-5 1-Lane Output Mode, 16-Bit Serialization t t ENCH ENCL t t FRAME DATA t SER 0 D13 D12 D11 D10 SAMPLE N-5 LTC2175-14/ LTC2174-14/LTC2173-14 N+1 t SER t SER D3 D13 D11 D9 D2 D12 D10 D8 SAMPLE N-4 217514 TD03 N+1 t SER t SER D13 D12 D11 D10 ...
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... LTC2175-14/ LTC2174-14/LTC2173-14 www.DataSheet4U.com TIMING DIAGRAMS ANALOG N INPUT – ENC + ENC – DCO + DCO – – OUT OUT#A SAMPLE N-6 + – OUT#B , OUT#B ARE DISABLED ANALOG INPUT – ENC + ENC – DCO + DCO – – OUT OUT#A SAMPLE N-6 + OUT#B ...
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... LTC2175-14: Shorted Input Histogram 6000 5000 4000 3000 2000 1000 0 60 8178 8180 8182 8184 OUTPUT CODE 217514 G07 LTC2175-14/ LTC2174-14/LTC2173-14 LTC2175-14: 8k Point FFT, f –1dBFS, 125Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 12288 16384 ...
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... LTC2175-14/ LTC2174-14/LTC2173-14 www.DataSheet4U.com TYPICAL PERFORMANCE CHARACTERISTICS LTC2175-14: SFDR vs Input Frequency, –1dB, 2V Range, 125Msps 100 150 200 250 300 INPUT FREQUENCY (MHz) LTC2175-14 Sample Rate, VDD 5MHz Sine Wave Input, –1dB 290 280 270 260 250 ...
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... INPUT LEVEL (dBFS) 217514 G23 LTC2175-14/ LTC2174-14/LTC2173-14 = 70MHz LTC2174-14: 8k Point FFT –1dBFS, 105Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 ...
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... G31 LTC2173-14: Differential Nonlinearity (DNL) 1.0 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 4096 8192 12288 16384 OUTPUT CODE 217514 G26 = 30MHz LTC2173-14: 8k Point FFT –1dBFS, 80Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 FREQUENCY (MHz) ...
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... 0.6 0.7 0.8 0.9 1 SENSE PIN (V) 217514 G55 LTC2175-14/ LTC2174-14/LTC2173-14 LTC2173-14: SFDR vs Input Level 70MHz, 2V Range, 80Msps IN 110 100 dBFS 250 300 350 –80 –70 –60 –50 –40 –30 –20 –10 ...
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... LTC2175-14/ LTC2174-14/LTC2173-14 www.DataSheet4U.com PIN FUNCTIONS + A (Pin 1): Channel 1 Positive Differential Analog IN1 Input. – A (Pin 2): Channel 1 Negative Differential Analog IN1 Input. V (Pin 3): Common Mode Bias Output, Nominally CM12 Equal to V /2. V should be used to bias the common DD CM mode of the analog inputs of channels 1 and 2. Bypass to ground with a 0.1μ ...
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... OUT4B /OUT4B , OUT4A /OUT4A Serial data outputs for Channel 4. In 1-lane output mode – + only OUT4A /OUT4A are used. LTC2174-14/LTC2173-14 – OUT3B /OUT3B Serial data outputs for Channel 3. In 1-lane output mode only OUT3A – /FR – DCO /DCO – ...
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... LTC2175-14/ LTC2174-14/LTC2173-14 www.DataSheet4U.com FUNCTIONAL BLOCK DIAGRAM CH 1 S/H ANALOG INPUT CH 2 S/H ANALOG INPUT CH 3 S/H ANALOG INPUT CH 4 S/H ANALOG INPUT V REF 1.25V REFERENCE 1μF RANGE SELECT REF SENSE BUF GND 18 1.8V ENC+ ENC– 14-BIT ADC CORE PLL 14-BIT ADC CORE 14-BIT ...
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... APPLICATIONS INFORMATION CONVERTER OPERATION The LTC2175-14/LTC2174-14/LTC2173-14 are low power, 4-channel, 14-bit, 125Msps/105Msps/80Msps A/D con- verters that are powered by a single 1.8V supply. The analog inputs should be driven differentially. The encode input can be driven differentially for optimal jitter perfor- mance, or single ended for lower power consumption. The digital outputs are serial LVDS to minimize the number of data lines ...
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... A/D. Reference The LTC2175-14/LTC2174-14/LTC2173-14 has an internal 1.25V voltage reference. For a 2V input range using the internal reference, connect SENSE to V range using the internal reference, connect SENSE to 50Ω ...
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... SENSE EXTERNAL REFERENCE 1μF Figure 9. Using an External 1.25V Reference LTC2174-14/LTC2173-14 and REFL should be as close to the pins as possible (not on the backside of the circuit board). Encode Input The signal quality of the encode inputs strongly affects the A/D noise performance. The encode inputs should be treated as analog signals— ...
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... LTC2175-14/ LTC2174-14/LTC2173-14 www.DataSheet4U.com APPLICATIONS INFORMATION The differential encode mode is recommended for sinu- soidal, PECL, or LVDS encode inputs (Figures 12 and 13). The encode inputs are internally biased to 1.2V through 10k equivalent resistance. The encode inputs can be taken above V (up to 3.6V), and the common mode DD range is from 1 ...
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... LVDS output pair. The termination Table 1. Maximum Sampling Frequency for All Serialization Modes. Note That These Limits Are for the LTC2175-14. The Sampling Frequency for the Slower Speed Grades Cannot Exceed 105MHz (LTC2174-14) or 80MHz (LTC2173-14). SERIALIZATION MODE 2-Lane ...
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... LTC2175-14/ LTC2174-14/LTC2173-14 www.DataSheet4U.com APPLICATIONS INFORMATION DATA FORMAT Table 2 shows the relationship between the analog input voltage and the digital data output bits. By default the output data format is offset binary. The 2’s complement format can be selected by serially programming mode control register A1. ...
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... A1 in the serial programming mode. DEVICE PROGRAMMING MODES The operating modes of the LTC2175-14/LTC2174-14/ LTC2173-14 can be programmed by either a parallel inter- face or a simple serial interface. The serial interface has more fl exibility and can program all available modes. The parallel interface is more limited and can only program some of the more commonly used modes ...
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... HEAT TRANSFER Most of the heat generated by the LTC2175-14/LTC2174-14/ LTC2173-14 is transferred from the die through the bot- tom-side Exposed Pad and package leads onto the printed circuit board. For good electrical and thermal performance, the Exposed Pad must be soldered to a large grounded pad on the PC board ...
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... REGISTER A4: TEST PATTERN LSB REGISTER (ADDRESS 04h TP7 TP6 Bit 7-0 TP7:TP0 Test Pattern Data Bits (LSB) TP7:TP0 Set the Test Pattern for Data Bit 7 Through Data Bit 0(LSB). LTC2174-14/LTC2173-14 Sleep/Nap Mode Control Bits ILVDS0 TERMON OUTOFF Digital Output Mode Control Bits ...
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... LTC2175-14/ LTC2174-14/LTC2173-14 www.DataSheet4U.com TYPICAL APPLICATIONS Silkscreen Top Inner Layer 2 GND 28 Top Side Inner Layer 3 21754314p ...
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... TYPICAL APPLICATIONS Inner Layer 4 Bottom Side LTC2175-14/ LTC2174-14/LTC2173-14 Inner Layer 5 Power Silkscreen Bottom 21754314p 29 ...
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... LTC2175-14/ LTC2174-14/LTC2173-14 www.DataSheet4U.com TYPICAL APPLICATIONS C17 1μF A IN1 R8 100 C29 A IN1 0.1μF A IN2 R92 100 A IN2 C1 C30 C2 2.2μF 0.1μF 0.1μF C3 0.1μF R93 A IN3 100 A IN3 C59 0.1μF A IN4 A IN4 30 LTC2175 Schematic SENSE C4 1μF R14 1k C5 1μ ...
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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, IF PRESENT 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 LTC2175-14/ LTC2174-14/LTC2173-14 5.50 REF (2 SIDES 0.115 TYP ...
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... LTC2175-14/ LTC2174-14/LTC2173-14 www.DataSheet4U.com RELATED PARTS PART NUMBER DESCRIPTION ADCs LTC2170-14/LTC2171-14/ 14-Bit, 25Msps/40Msps/65Msps LTC2172-14 1.8V Quad ADCs, Ultralow Power LTC2170-12/LTC2171-12/ 12-Bit, 25Msps/40Msps/65Msps LTC2172-12 1.8V Quad ADCs, Ultralow Power LTC2173-12/LTC2174-12/ 12-Bit, 80Msps/105Msps/125Msps LTC2175-12 1.8V Quad ADCs, Ultralow Power LTC2202/LTC2203 16-Bit, 10Msps/25Msps, 3.3V ADCs LTC2204/LTC2205 16-Bit, 40Msps/65Msps 3 ...