LTC2172-12 Linear Technology, LTC2172-12 Datasheet
LTC2172-12
Related parts for LTC2172-12
LTC2172-12 Summary of contents
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... LTC2172-12/ LTC2171-12/LTC2170-12 12-Bit, 65Msps/40Msps/ ® 2172-12/LTC2171-12/LTC2170-12 are 4-channel, allows undersampling of IF frequencies with RMS . RMS + – and ENC inputs may be driven differentially LTC2172-12, 65Msps, 2-Tone FFT 70MHz and 75MHz IN 0 –10 –20 –30 –40 –50 –60 –70 –80 – ...
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... LTC2172-12/ LTC2171-12/LTC2170-12 ABSOLUTE MAXIMUM RATINGS (Notes 1 and 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 LTC2172C, LTC2171C, LTC2170C............. 0° ...
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... IN External Reference Mode Per Pin, 65Msps Per Pin, 40Msps Per Pin, 25Msps + – 0 < < < PAR/SER < 0.625 < SENSE < 1.3V Figure 6 Test Circuit LTC2172-12/ LTC2171-12/LTC2170-12 LTC2171-12 LTC2170-12 MAX MIN TYP MAX MIN TYP –1 ±0.3 1 –1 ±0.3 0.5 – ...
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... Output Resistance –400μA < I REF V Line Regulation 1.7V < V REF 4 l The denotes the specifi cations which apply over the full operating temperature range, = –1dBFS. (Note 5) IN LTC2172-12 CONDITIONS MIN TYP 5MHz Input 71 l 30MHz Input 69.7 71 70MHz Input 70.9 140MHz Input 70 ...
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... 1.8V, SDO = SDO = 0V to 3.6V l 100Ω Differential Load, 3.5mA Mode l 100Ω Differential Load, 1.75mA Mode l 100Ω Differential Load, 3.5mA Mode l 100Ω Differential Load, 1.75mA Mode Termination Enabled 1.8V DD LTC2172-12/ MIN TYP MAX UNITS 0.2 V 1.2 V 1.1 1.6 V 0.2 3 kΩ ...
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... The denotes the specifi cations which apply over the full operating temperature = 25°C. (Note 5) A LTC2172-12 MIN TYP MAX 7.3 7.69 100 l 2 7.69 100 l 7.3 7.69 100 l 2 7.69 100 0 LTC2171-12 LTC2170-12 ...
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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 with differential drive, data rate is 1000Mbps 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. LTC2172-12/ LTC2171-12/LTC2170-12 MIN TYP MAX • • ...
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... LTC2172-12/ LTC2171-12/LTC2170-12 TIMING DIAGRAMS ANALOG INPUT – ENC + ENC – DCO + DCO – – OUT OUT#A – OUT OUT#B SAMPLE N-6 *D AND D ARE EXTRA NON-DATA BITS FOR COMPLETE SOFTWARE COMPATIBILITY WITH THE 14-BIT X Y VERSIONS OF THESE A/Ds. DURING NORMAL NON-OVERRANGED OPERATION D LOGIC 0 ...
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... D0 D10 SAMPLE N-5 1-Lane Output Mode, 16-Bit Serialization t ENCL t t FRAME DATA t SER D10 AND D ARE SET LTC2172-12/ LTC2171-12/LTC2170-12 t SER t SER D3 D1 D11 D10 D8 D6 217212 TD03 SAMPLE N SER t SER ...
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... LTC2172-12/ LTC2171-12/LTC2170-12 TIMING DIAGRAMS t ANALOG INPUT N – ENC + ENC – DCO + DCO – – OUT OUT#A SAMPLE N-6 + – OUT#B , OUT#B ARE DISABLED *D AND D ARE EXTRA NON-DATA BITS FOR COMPLETE SOFTWARE COMPATIBILITY WITH THE 14-BIT X Y VERSIONS OF THESE A/Ds. DURING NORMAL NON-OVERRANGED OPERATION D LOGIC 0 ...
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... FREQUENCY (MHz) 217212 G02 = 70MHz LTC2172-12: 8k Point FFT –1dBFS, 65Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 FREQUENCY (MHz) ...
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... G53 LTC2171-12: Differential Nonlinearity (DNL) 1.0 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 4096 0 1024 2048 OUTPUT CODE 217212 G21 LTC2172-12: SNR vs Input Level 70MHz, 2V Range, 65Msps –60 –40 –30 –50 0 INPUT LEVEL(dBFS) 217212 G12 LTC2172-12: SNR vs SENSE 5MHz, – ...
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... INPUT LEVEL (dBFS) LTC2172-12/ LTC2171-12/LTC2170-12 = 69MHz LTC2171-12: 8k Point FFT –1dBFS, 40Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 – ...
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... LTC2172-12/ LTC2171-12/LTC2170-12 TYPICAL PERFORMANCE CHARACTERISTICS LTC2171-12: SNR vs SENSE 5MHz, –1dBFS 0.6 0.7 0.8 0.9 1 1.1 1.2 SENSE PIN (V) LTC2170-12: 8k Point FFT 5MHz IN –1dBFS, 25Msps 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 www.DataSheet4U.com –120 FREQUENCY (MHz) LTC2170-12: 8k Point FFT 140MHz – ...
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... G49 LTC2170-12: SNR vs SENSE 5MHz, –1dBFS 0.6 0.7 0.8 0.9 1.0 SENSE PIN (V) 217212 G55 LTC2172-12/ LTC2171-12/LTC2170-12 LTC2170-12: SFDR vs Input Level 70MHz, 2V Range, 25Msps IN 110 100 dBFS –80 –70 –60 –50 –40 –30 –20 –10 ...
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... LTC2172-12/ LTC2171-12/LTC2170-12 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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... DCO /DCO OUT2B Pins 39/40): Serial Data Outputs for Channel 1-lane output mode, only OUT2A SENSE OUT2B Pins 43/44): Serial Data Outputs for Channel 1. In 1-lane output mode, only OUT1A LTC2172-12/ – + – + /OUT4B , OUT4A /OUT4A (Pins 23/24, – + /OUT4A are used. ...
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... LTC2172-12/ LTC2171-12/LTC2170-12 FUNCTIONAL BLOCK DIAGRAM CHANNEL 1 SAMPLE- ANALOG AND-HOLD INPUT CHANNEL 2 SAMPLE- ANALOG AND-HOLD INPUT CHANNEL 3 SAMPLE- ANALOG AND-HOLD INPUT CHANNEL 4 SAMPLE- ANALOG AND-HOLD INPUT V REF 1.25V REFERENCE 1μF RANGE SELECT www.DataSheet4U.com REF SENSE BUF GND 18 1. 12-BIT ADC CORE ...
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... APPLICATIONS INFORMATION CONVERTER OPERATION The LTC2172-12/LTC2171-12/LTC2170-12 are low power, 4-channel, 12-bit, 65Msps/40Msps/25Msps A/D convert- ers 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 performance, or single-ended for lower power consumption. The digital outputs are serial LVDS to minimize the number of data lines ...
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... HIGH SPEED 0.1μF 200Ω 200Ω DIFFERENTIAL 0.1μF AMPLIFIER 25Ω 12pF – 0.1μF – 25Ω Figure 7. Front-End Circuit Using a High Speed Differential Amplifi 0.1μ LTC2172-12 1.8pF – 217212 F05 LTC2172-12 – 217212 F07 21721012f ...
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... APPLICATIONS INFORMATION Reference The LTC2172-12/LTC2171-12/LTC2170-12 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 ground. For a 2V input range with an external reference, apply a 1.25V reference voltage to SENSE (Figure 9). ...
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... In the parallel programming mode the duty cycle stabilizer is always enabled. DIGITAL OUTPUTS The digital outputs of the LTC2172-12/LTC2171-12/ LTC2170-12 are serialized LVDS signals. Each channel outputs two bits at a time (2-lane mode) or one bit at a should have fast rise and time (1-lane mode) ...
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... APPLICATIONS INFORMATION Table 1. Maximum Sampling Frequency for All Serialization Modes. Note That These Limits Are for the LTC2172-12. The Sampling Frequency for the Slower Speed Grades Cannot Exceed 40MHz (LTC2171-12) or 25MHz (LTC2170-12). SERIALIZATION MODE 2-Lane 16-Bit Serialization 2-Lane 14-Bit Serialization 2-Lane ...
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... Nap mode is enabled by the mode control register A1 in the serial programming mode. DEVICE PROGRAMMING MODES The operating modes of the LTC2172-12/LTC2171-12/ LTC2170-12 can be programmed by either a parallel interface or a simple serial interface. The serial interface has more fl exibility and can program all available modes. ...
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... To perform a software reset, bit D7 in the reset register is written with a logic 1. After the reset is complete, bit D7 is automatically set back to zero TWOSCOMP SLEEP NAP_4 Sleep/Nap Mode Control Bits LTC2172-12/ LTC2171-12/LTC2170- NAP_3 NAP_2 NAP_1 21721012f 25 ...
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... LTC2172-12/ LTC2171-12/LTC2170-12 APPLICATIONS INFORMATION REGISTER A2: OUTPUT MODE REGISTER (ADDRESS 02h ILVDS2 ILVDS1 Bits 7-5 ILVDS2:ILVDS0 LVDS Output Current Bits 000 = 3.5mA LVDS Output Driver Current 001 = 4.0mA LVDS Output Driver Current 010 = 4.5mA LVDS Output Driver Current 011 = Not Used 100 = 3 ...
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... HEAT TRANSFER Most of the heat generated by the LTC2172-12 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 must be soldered to a large grounded pad on the PC board ...
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... LTC2172-12/ LTC2171-12/LTC2170-12 TYPICAL APPLICATIONS Silkscreen Top Inner Layer 2 GND www.DataSheet4U.com 28 Top Side Inner Layer 3 21721012f ...
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... TYPICAL APPLICATIONS Inner Layer 4 Bottom Side www.DataSheet4U.com LTC2172-12/ LTC2171-12/LTC2170-12 Inner Layer 5 Power Silkscreen Bottom 21721012f 29 ...
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... LTC2172-12/ LTC2171-12/LTC2170-12 TYPICAL APPLICATIONS C17 1μF A IN1 C29 A IN1 0.1μF A IN2 A IN2 C1 C30 C2 2.2μF 0.1μF 0.1μF C3 0.1μF A IN3 A IN3 C59 www.DataSheet4U.com 0.1μF A IN4 A IN4 30 LTC2172 Schematic SENSE C4 R14 1μ 1μ IN1 2 – ...
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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 LTC2172-12/ LTC2171-12/LTC2170-12 5.50 REF (2 SIDES ...
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