KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Description The Kenet KAD2708C is the industry's lowest power, 8-bit, high performance Analog-to-Digital converter. The converter runs at sampling rates up to 275MSPS, and is fabricated with Kenet's proprietary FemtoCharge(R) CMOS technology. Users can now obtain industry-leading SNR and SFDR specifications while nearly halving power consumption. Sampling rates of 210, 170 and 105MSPS are also available in the same pin-compatible package and in versions with 10-bit resolution. Kenet's KAD2708L offers this performance with LVDS outputs. All are available in 68-pin RoHS-compliant QFN packages with exposed paddle. Performance is specified over the full industrial temperature range (-40 to +85C). Key Specifications * * * SNR of 48.8dB at Nyquist SFDR of 68dBc at Nyquist Power consumption 265mW at fS = 275MSPS Features * * * * * * * * On-chip reference Internal track and hold 1.5VPP differential input voltage 600MHz analog input bandwidth Two's complement or binary output Over-range indicator Selectable /2 Clock Input LVCMOS compatible outputs Applications * * * * * * * * * High-Performance Data Acquisition Portable Oscilloscope Medical Imaging Cable Head Ends Power-Amplifier Linearization Radar and Satellite Antenna Array Processing Broadband Communications Local Multipoint Distribution System (LMDS) Communications Test Equipment Resolution, Speed LVDS Outputs LVCMOS Outputs 8 Bits 350MSPS KAD2708L-35 10 Bits 275MSPS KAD2710L-27 KAD2710C-27 8 Bits 275MSPS KAD2708L-27 KAD2708C-27 10 Bits 210MSPS KAD2710L-21 KAD2710C-21 8 Bits 210MSPS KAD2708L-21 KAD2708C-21 10 Bits 170MSPS KAD2710L-17 KAD2710C-17 8 Bits 170MSPS KAD2708L-17 KAD2708C-17 10 Bits 105MSPS KAD2710L-10 KAD2710C-10 8 Bits 105MSPS KAD2708L-10 KAD2708C-10 Table 1. Pin-Compatible Products 300 Unicorn Park Dr., Woburn, MA 01801 Sales: 1-781-497-0060 FemtoCharge is a registered trademark of Kenet, Inc. Rev 1.1 Sales@kenetinc.com Copyright (c) 2007, Kenet, Inc. Page 1 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Absolute Maximum Ratings1 Parameter Min Max Unit AVDD2 to AVSS -0.4 2.1 V AVDD3 to AVSS -0.4 3.7 V OVDD2 to OVSS -0.4 2.1 V Analog Inputs to AVSS -0.4 AVDD3 + 0.3 V Clock Inputs to AVSS -0.4 AVDD2 + 0.3 V Logic Inputs to AVSS (VREFSEL, CLKDIV) -0.4 AVDD3 + 0.3 V Logic Inputs to OVSS (RST, 2SC) -0.4 OVDD2 + 0.3 V VREF TO AVSS -0.4 AVDD3 + 0.3 V Analog Output Currents 10 mA Logic Output Currents 10 mA CMOS Output Currents 20 mA Operating Temperature -40 85 C Storage Temperature -65 150 C 150 C Junction Temperature 1. Exposing the device to levels in excess of the maximum ratings may cause permanent damage. Exposure to maximum conditions for extended periods may affect device reliability. Thermal Impedance Parameter Junction to Paddle2 Symbol Typ Unit JP 30 C/W 2. Paddle soldered to ground plane. ESD Electrostatic charge accumulates on humans, tools and equipment, and may discharge through any metallic package contacts (pins, balls, exposed paddle, etc.) of an integrated circuit. Industry-standard protection techniques have been utilized in the design of this product. However, reasonable care must be taken in the storage and handling of ESD sensitive products. Contact Kenet for the specific ESD sensitivity rating of this product. Rev 1.1 Page 2 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Electrical Specifications All specifications apply under the following conditions unless otherwise noted: AVDD2 = 1.8V, AVDD3 = 3.3V, OVDD = 1.8V. TA = -40C to +85C, Typ values at 25C. fSAMPLE = 275MSPS fIN = Nyquist. DC Specifications Parameter Symbol Conditions Min Typ Max Units 1.8V Analog Supply Voltage AVDD2 1.7 1.8 1.9 V 3.3V Analog Supply Voltage AVDD3 3.15 3.3 3.45 V 1.8V Output Supply Voltage OVDD 1.7 1.8 1.9 V 1.8V Analog Supply Current IAVDD2 44 mA 3.3V Analog Supply Current IAVDD3 41 mA 1.8V Output Supply Current IOVDD 26 mA PD 261 mW Power Requirements Power Dissipation Rev 1.1 Page 3 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Analog Specifications Parameter Symbol Conditions Min Typ Max Units 1.4 1.5 1.6 VPP Analog Input Full-Scale Differential Analog Input Voltage Gain Temperature Coefficient VIN AVTC Full Power Bandwidth Full Temp FPBW 90 ppm/C 600 MHz Clock Input Sampling Clock Frequency Range fSAMPLE 50 275 MHz CLKP, CLKN P-P Differential Input Voltage VCDI 0.5 1.8 VPP CLKP, CLKN Differential Input Resistance RCDI 10 M CLKP, CLKN Common-Mode Input Voltage VCCI 0.9 V Reference Internal Reference Voltage VREF Reference Voltage Temperature Coefficient VRTC Common-Mode Output Voltage VCM 1.18 1.21 Full Temp 1.24 V 38 ppm/C 0.86 V AC Specifications Parameter Conditions Min Typ SNR Full Temp 45.8 48.8 dB Signal to Noise and Distortion SINAD Full Temp 45.7 48.7 dB Effective Number of Bits ENOB Full Temp 7.3 7.8 Bits Spurious Free Dynamic Range SFDR Full Temp 63 68 dBc Two-Tone SFDR 2TSFDR f1=133MHz, f2=135MHz 67 dBc Signal to Noise Ratio Symbol Max Units Integral Nonlinearity INL -0.8 0.2 0.8 LSB Differential Nonlinearity DNL -0.3 0.2 0.4 LSB Power Supply Rejection Ratio PSRR 42 66 Word Error Rate WER Rev 1.1 dB 1x10-12 Page 4 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Digital Specifications Parameter Symbol Conditions Min Typ Max Units Inputs 0.8*AVDD3 High Input Voltage (VREFSEL) VREFSEL VIH Low Input Voltage (VREFSEL) VREFSEL VIL Input Current High (VREFSEL) VREFSEL IIH VIN = AVDD3 0 Input Current Low (VREFSEL) VREFSEL IIL VIN = AVSS 25 High Input Voltage (CLKDIV) CLKDIV VIH Low Input Voltage (CLKDIV) CLKDIV VIL Input Current High (CLKDIV) CLKDIV IIH VIN = AVDD3 25 Input Current Low (CLKDIV) CLKDIV IIL VIN = AVSS 0 0.2*AVDD3 V 1 10 A 65 75 A 0.8*AVDD3 V 0.2*AVDD3 V 65 75 A 1 10 A 0.8*OVDD2 High Input Voltage (RST,2SC) RST,2SC VIH Low Input Voltage (RST,2SC) RST,2SC VIL Input Current High (RST,2SC) RST,2SC IIH VIN = OVDD 0 Input Current Low (RST,2SC) RST,2SC IIL VIN = OVSS 25 Input Capacitance V V 0.2*OVDD2 V 1 10 A 50 75 A CDI 3 pF Voltage Output High VOH 1.8 V Voltage Output Low VOL 0 V Output Rise Time tR 1.8 ns Output Fall Time tF 1.4 ns CMOS Outputs Rev 1.1 Page 5 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Timing Diagram Figure 1. LVCMOS Timing Diagram Timing Specifications Parameter Symbol Min Typ Max Units Aperture Delay tA 1.7 ns RMS Aperture Jitter jA 200 fs Input Clock to Data Propagation Delay tPD 1.8 ns Input Clock to Output Clock Propagation Delay tCPD 1.3 ns Output Clock to Data Propagation Delay tDC 470 ps Output Data to Output Clock Setup Time tSU 3 ns Output Clock to Output Data Hold Time tH 75 ps Latency (Pipeline Delay) L 28 cycles Over Voltage Recovery tOVR 1 cycle Rev 1.1 Page 6 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Pin Descriptions Pin # Name Function 1, 14, 18, 20 AVDD2 1.8V Analog Supply 2, 7, 10, 19, 21, 24 AVSS Analog Supply Return 3 VREF Reference Voltage Out/In 4 VREFSEL 5 VCM Reference Voltage Select (0:Int 1:Ext) Common Mode Voltage Output 6, 15, 16, 25 AVDD3 3.3V Analog Supply 8, 9 INP, INN Analog Input Positive, Negative 11-13, 29-36, 37, 39, 42, 46, 48, DNC Do Not Connect 50, 53, 54, 56, 58, 62, 63, 67 17 22, 23 26, 45, 61 27, 41, 44, 60 CLKDIV CLKN, CLKP OVSS OVDD2 Clock Divide by Two (Active Low) Clock Input Complement, True Output Supply Return 1.8V CMOS Supply 28 RST Power On Reset (Active Low) 38 D0 LVCMOS Bit 0 (LSB) Output 40 D1 LVCMOS Bit 1 Output 43 CLKOUT 47 D2 LVCMOS Bit 2 Output 49 D3 LVCMOS Bit 3 Output 51 D4 LVCMOS Bit 4 Output 53 D5 LVCMOS Bit 5 Output 55 D6 LVCMOS Bit 6 Output 57 D7 LVCMOS Bit 7 Output 59 OR Over Range 64-66 LVCMOS Clock Output Connect to OVDD2 68 2SC Two's Complement Select (Active Low) Exposed Paddle AVSS Analog Supply Return Rev 1.1 Page 7 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 2SC DNC OVDD2 OVDD2 OVDD2 DNC DNC OVSS OVDD2 ORP DNC D7 DNC D6 DNC D5 DNC Pin Configuration 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 68 QFN Top View Not to Scale 51 50 49 48 47 46 45 44 43 42 41 D4 DNC D3 DNC 40 39 D1 DNC 38 37 36 35 D0 DNC DNC DNC D2 DNC OVSS OVDD2 CLKOUT DNC OVDD2 AVDD2 AVSS AVDD2 AVSS CLKN CLKP AVSS AVDD3 OVSS OVDD2 RST DNC DNC DNC DNC DNC DNC 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 AVDD2 AVSS VREF VREFSEL VCM AVDD3 AVSS INP INN AVSS DNC DNC DNC AVDD2 AVDD3 AVDD3 CLKDIV Figure 2. Pin Configuration Rev 1.1 Page 8 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Typical Operating Characteristics AVDD3=3.3V, AVDD2=OVDD2 =1.8V, TAMBIENT (TA)=25C, fSAMPLE=275MHz, VIN=6.865MHz @ -0.5dBFS unless noted. 50 45 SFDR (dB) SNR (dB) 40 35 30 25 20 15 -30 -25 -20 -15 -10 -5 0 75 70 65 60 55 50 45 40 35 30 25 -30 -25 -20 -15 -10 -5 0 Input Amplitude (dBFS) Analog Input Amplitude (dBFS) Figure 3. SNR vs. Vin Figure 4. SFDR vs. Vin Power Dissipation (PD) (mW) 280 HD2, HD3 dBc -30 -40 -50 HD3 -60 HD2 -70 -80 -30 -25 -20 -15 -10 -5 260 240 220 200 180 160 140 120 100 0 50 100 Input Amplitude (dBFS) Figure 5. HD2, 3 vs. Vin 250 300 Figure 6. Power Dissipation vs. fSAMPLE 50 -65 -70 49.5 HD3 -75 49 dBc SNR (dB) 150 200 f SAMPLE (f S ) (MHz) -80 48.5 HD2 -85 48 -90 50 75 100 125 150 175 200 225 250 275 300 f SAMPLE (MHz) Figure 7. SNR vs. fSAMPLE Rev 1.1 50 75 100 125 150 175 200 225 250 275 300 f SAMPLE (MHz) Figure 8. HD2, 3 vs. fSAMPLE Page 9 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter AVDD3=3.3V, AVDD2=OVDD2 =1.8V, TAMBIENT (TA)=25C, fSAMPLE=275MHz, VIN = 6.865MHz @ -0.5dBFS unless noted. 72 0.25 0.2 0.15 0.1 70 DNL (LSBs) SFDR (dBc) 71 69 0.05 0 -0.05 -0.1 68 -0.15 -0.2 67 50 75 100 125 150 175 200 225 250 275 -0.25 300 0 32 64 96 f SAMPLE (MHz) 0.25 50,000 0.2 45,000 0.15 40,000 0.1 35,000 0.05 30,000 0 -0.05 224 15,000 -0.15 10,000 -0.2 5,000 0 32 64 96 128 code 160 192 224 0 126 255 127 code 128 129 Figure 12. Noise Histogram 0 0 Vin = -0.25dBFS -10 Vin = -0.22dBFS -20 SNR = 49.2dB -20 SNR = 49.0dB -30 SFDR = 71.0dBc -30 SFDR = 69.2dBc -40 SINAD = 49.0dB -40 SINAD = 49.0dB -50 HD2 = -83dBc -50 HD2 = -77dBc -60 HD3 = -66dBc -60 HD3 = -69dBc Amplitude (dB) -10 -70 -70 -80 -80 -90 -90 -100 255 20,000 Figure 11. Integral Nonlinearity vs. Output Code Amplitude (dB) 192 25,000 -0.1 -0.25 160 Figure 10. Differential Nonlinearity vs. Output Code Counts INL (LSBs) Figure 9. SFDR vs. fSAMPLE 128 code 0 20 40 60 80 Frequency (MHz) 100 120 Figure 13. Output Spectrum at 6.865MHz Rev 1.1 -100 0 20 40 60 80 Frequency (MHz) 100 120 Figure 14. Output Spectrum at 68.465MHz Page 10 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter AVDD3=3.3V, AVDD2=OVDD2 =1.8V, TAMBIENT (TA)=25C, fSAMPLE=275MHz unless noted. 0 -10 Vin = -0.27 -10 Vin = -0.26dBFS -20 SNR = 49.1dB -20 SNR = 49.1dB -30 SFDR = 66.8dBc -30 SFDR = 70.3dBc -40 SINAD = 48.8dB -40 SINAD = 48.9dB -50 HD2 = -85dBc -50 HD2 = -79dBc -60 HD3 = -68dBc -60 HD3 = -69dBc Amplitude (dB) Amplitude (dB) 0 -70 -70 -80 -80 -90 -90 -100 -100 0 20 40 60 80 Frequency (MHz) 100 120 Figure 15. Output Spectrum at 130.565MHz 0 20 40 60 80 Frequency (MHz) 100 120 Figure 16. Output Spectrum at 143.155MHz Amplitude (dB) 0 -10 Vin = -0.25dBFS -20 SNR = 48.5dB -30 SFDR = 58.2dBc -40 SINAD = 47.8dB -50 HD2 = -58dBc -60 HD3 = -61dBc -70 -80 -90 -100 0 20 40 60 80 Frequency (MHz) 100 120 Figure 17. Output Spectrum at 492.965MHz Rev 1.1 Page 11 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Functional Description The KAD2708 is based upon a eight bit, 275MSPS A/D converter in a pipelined architecture. The input voltage is captured by a sample & hold circuit and converted to a unit of charge. Proprietary charge domain techniques are used to compare the input to a series of reference charges. These comparisons determine the digital code for each input value. The converter pipeline requires 24 sample clocks to produce a result. Digital error correction is also applied, resulting in a total latency of 28 clock cycles. This is evident to the user as a latency between the start of a conversion and the data being available on the digital outputs. At start-up, a self-calibration is performed to minimize gain and offset errors. The reset pin (RST) is initially held low internally at power-up and will remain in that state until the calibration is complete. The clock frequency should remain fixed during this time. the system. Additionally, an externally provided reference can be changed from the nominal value to adjust the full-scale input voltage within a limited range. To select whether the full-scale reference is internally generated or externally provided, the digital input port VREFSEL should be set appropriately, low for internal or high for external. This pin also has an internal 18k pull-up resistor. To use the internally generated reference VREFSEL can be tied directly to AVSS, and to use an external reference VREFSEL can be allowed to float. Analog Input The fully differential ADC input (INP/INN) connects to the sample and hold circuit. The ideal full-scale input voltage is 1.5VPP, centered at the VCM voltage of 0.86V as shown in Figure 18. Calibration accuracy is maintained for the sample rate at which it is performed, and therefore should be repeated if the clock frequency is changed by more than 10%. Recalibration can be initiated via the RST pin, or power cycling, at any time. Reset The KAD2708C resets and calibrates automatically on power-up. To force a reset and initiate recalibration of the ADC after power-up, connect an open-drain output device to drive pin 28 (RST) and pull low for at least ten sample clock periods. Do not use a device with a pull-up on the reset pin, as it may prevent the KAD2708 from properly executing the power-on reset. Voltage Reference The VREF pin is the full-scale reference, which sets the full-scale input voltage for the chip and requires a bypass capacitor of 0.1uF or larger. An internally generated reference voltage is provided from a bandgap voltage buffer. This buffer can sink or source up to 50A externally. An external voltage may be applied to this pin to provide a more accurate reference than the internally generated bandgap voltage or to match the full-scale reference among a system of KAD2708C chips. One option in the latter configuration is to use one KAD2708C's internally generated reference as the external reference voltage for the other chips in Rev 1.1 Figure 18. Analog Input Range Best performance is obtained when the analog inputs are driven differentially in an ac-coupled configuration. The common mode output voltage, VCM, should be used to properly bias each input as shown in Figures 19 and 20. An RF transformer will give the best noise and distortion performance for wideband and/or high intermediate frequency (IF) inputs. The recommended biasing is shown in Figure 19. Figure 19. Transformer Input Page 12 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter The value of the termination resistor should be determined based on the desired impedance. The differential input impedance of the KAD2708 is 10M. A differential amplifier can be used in applications that require dc coupling, at the expense of reduced dynamic performance. In this configuration the amplifier will typically reduce the achievable SNR and distortion performance. A typical differential amplifier configuration is shown in Figure 20. rate, then use the KAD2708C's divide-by-2 to generate a 50%-duty-cycle clock. The divider only uses the rising edge of the clock, so 50% clock duty cycle is assured . CLKDIV Pin Divide Ratio AVSS 2 AVDD 1 Table 3. CLKDIV Pin Settings Jitter In a sampled data system, clock jitter directly impacts the achievable SNR performance. The theoretical relationship between clock jitter and maximum SNR is shown in Equation 1 and is illustrated in Figure 22. 1 SNR = 20 log 10 2 f IN t J Figure 20. Differential Amplifier Input Clock Input The clock input circuit is a differential pair (see Figure 24). Driving these inputs with a high level (up to 1.8VPP on each input) sine or square wave will provide the lowest jitter performance. The recommended drive circuit is shown in Figure 21. The clock inputs can be driven single-ended, but this is not recommended as performance will suffer. Where tj is the RMS uncertainty in the sampling instant. Equation 1. This relationship shows the SNR that would be achieved if clock jitter were the only non-ideal factor. In reality, achievable SNR is limited by internal factors such as differential nonlinearity, aperture jitter and thermal noise. 100 95 tj=0.1ps 90 14 Bits SNR - dB 85 80 tj=1ps 12 Bits 75 70 tj=10ps 65 60 10 Bits tj=100ps 55 Figure 21. Recommended Clock drive The CLKDIV pin is a 1.8V CMOS control pin (input) that selects whether the input clock frequency is passed directly to the ADC or divided by two. Applying a low level will divide by two; 1.8V applied (or left floating) will not divide. Use of the clock divider is optional. The KAD2708C's ADC requires a clock with 50% duty cycle for optimum performance. If such a clock is not available, one option is to generate twice the desired sampling Rev 1.1 50 1 10 100 1000 Input Frequency - MHz Figure 22. SNR vs. Clock Jitter Any internal aperture jitter combines with the input clock jitter, in a root-sum-square fashion since they are not statistically correlated, and this determines the total jitter in the system. The total jitter, combined with other noise sources, then determines the achievable SNR. Page 13 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Equivalent Circuits Layout Considerations Split Ground and Power Planes Data converters operating at high sampling frequencies require extra care in PC board layout. Many complex board designs benefit from isolating the analog and digital sections. Analog supply and ground planes should be laid out under signal and clock inputs. Locate the digital planes under outputs and logic pins. Grounds should be joined under the chip. Figure 23. Analog Inputs Clock Input Considerations Use matched transmission lines to the inputs for the analog input and clock signals. Locate transformers, drivers and terminations as close to the chip as possible. Bypass and Filtering Bulk capacitors should have low equivalent series resistance. Tantalum is a good choice. For best performance, keep ceramic bypass capacitors very close to device pins. Longer traces will increase inductance, resulting in diminished dynamic performance and accuracy. Make sure that connections to ground are direct and low impedance. Avoid forming ground loops. LVCMOS Outputs Output traces and connections must be designed for 50 characteristic impedance. Figure 24. Clock Inputs Unused Inputs Three of the four standard logic inputs (RESET, CLKDIV, 2SC) which will not be operated do not require connection for best ADC performance. These inputs can be left open if they are not used. VREFSEL must be held low for internal reference, but can be left open for external reference. Figure 25. LVCMOS Outputs Rev 1.1 Page 14 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Definitions Analog Input Bandwidth is the analog input frequency at which the spectral output power at the fundamental frequency (as determined by FFT analysis) is reduced by 3dB from its full-scale low-frequency value. This is also referred to as Full Power Bandwidth. Aperture Delay or Sampling Delay is the time required after the rise of the clock input for the sampling switch to open, at which time the signal is held for conversion. Aperture Jitter is the RMS variation in aperture delay for a set of samples. Clock Duty Cycle is the ratio of the time the clock wave is at logic high to the total time of one clock period. of all other spectral components below one half the clock frequency, including harmonics but excluding DC. Signal-to-Noise Ratio (without Harmonics) is the ratio of the RMS signal amplitude to the sum of all other spectral components below one-half the sampling frequency, excluding harmonics and DC. Spurious-Free-Dynamic Range (SFDR) is the ratio of the RMS signal amplitude to the RMS value of the peak spurious spectral component. The peak spurious spectral component may or may not be a harmonic. Two-Tone SFDR is the ratio of the RMS value of either input tone to the RMS value of the peak spurious component. The peak spurious component may or may not be an IMD product. Differential Non-Linearity (DNL) is the deviation of any code width from an ideal 1 LSB step. Effective Number of Bits (ENOB) is an alternate method of specifying Signal to Noise-and-Distortion Ratio (SINAD). In dB, it is calculated as: ENOB = (SINAD-1.76) / 6.02. Integral Non-Linearity (INL) is the deviation of each individual code from a line drawn from negative fullscale (1/2 LSB below the first code transition) through positive full-scale (1/2 LSB above the last code transition). The deviation of any given code from this line is measured from the center of that code. Least Significant Bit (LSB) is the bit that has the smallest value or weight in a digital word. Its value in terms of input voltage is VFS/(2N-1) where N is the resolution in bits. Missing Codes are output codes that are skipped and will never appear at the ADC output. These codes cannot be reached with any input value. Most Significant Bit (MSB) is the bit that has the largest value or weight. Its value in terms of input voltage is VFS/2. Pipeline Delay is the number of clock cycles between the initiation of a conversion and the appearance at the output pins of the corresponding data. Power Supply Rejection Ratio (PSRR) is the ratio of a change in power supply voltage to the input voltage necessary to negate the resultant change in output code. Signal to Noise-and-Distortion (SINAD) is the ratio of the RMS signal amplitude to the RMS value of the sum Rev 1.1 Page 15 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Outline Dimensions D D/2 D1 D1/2 PIN 1 ID 0.80 DIA E/2 E1/2 E1 TOP VIEW E C C b A1 e SECTION "C-C" SCALE: NONE TERMINAL TIP A b A1 4X P D2 D2/2 4X P 0.45 E2 16Xe REF. E2/2 0.25 MIN L e 0.25 MIN SEATING PLANE 16Xe REF. BOTTOM VIEW Rev 1.1 Page 16 of 17 KAD2708C 8-Bit, 275MSPS Analog-to-Digital Converter Package Dimensions (mm) Ref Min Nom Max A - 0.90 1.00 A1 0.00 0.01 0.05 Per JEDEC MO-220 b 0.18 0.23 0.30 Measured between 0.20 and 0.25mm from plated terminal tip D 10.00 BSC D1 9.75 BSC D2 7.55 7.70 e 0.50 BSC E 10.00 BSC E1 9.75 BSC Note 7.85 E2 7.55 7.70 7.85 L 0.50 0.60 0.65 N 68 Total terminals ND 17 Terminals in D (x) direction NE 17 Terminals in E (y) direction 0 P 0 12' 0.42 0.60 Ordering Guide This product is compliant with EU directive 2002/95/EC regarding the Restriction of Hazardous Sub- RoHS stances (RoHS). Contact Kenet for a materials declaration for this product. Rev 1.1 Model Speed Package Temp. Range KAD2708C-27Q68 275MSPS 68-QFN EP -40C to +85C KAD2708C-21Q68 210MSPS 68-QFN EP -40C to +85C KAD2710C-17Q68 170MSPS 68-QFN EP -40C to +85C KAD2710C-10Q68 105MSPS 68-QFN EP -40C to +85C Page 17 of 17