Data Sheet A m p l i fy t h e H u m a n E x p e r i e n c e CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters 13-bit resolution n 20/40/65/80MSPS maximum sampling rate n Ultra-low power dissipation: 30/55/85/102mW n SNR 72dB at 80MSPS and 8MHz FIN n Internal reference circuitry n 1.8V core supply voltage n 1.7V – 3.6V I/O supply voltage n Parallel CMOS output n 64-pin QFN package (TQFP-64 package option also available) n Dual channel n Pin compatible with CDK2308 APPLICATIONS Handheld Communication, PMR, SDR n Medical Imaging n Portable Test Equipment n Digital Oscilloscopes n Baseband / IF Communication n Video Digitizing n CCD Digitizing Several idle modes with fast startup times exist. Each channel can be independently powered down and the entire chip can either be put in Standby Mode or Power Down mode. The different modes are optimized to allow the user to select the mode resulting in the smallest possible energy consumption during idle mode and startup. The CDK2307 has a highly linear THA optimized for frequencies up to 70MHz. The differential clock interface is optimized for low jitter clock sources and supports LVDS, LVPECL, sine wave and CMOS clock inputs. Functional Block Diagram CLKP n The CDK2307 is a high performance, low power dual Analog-to-Digital Converter (ADC). The ADC employs internal reference circuitry, a CMOS control interface and CMOS output data, and is based on a proprietary structure. Digital error correction is employed to ensure no missing codes in the complete full scale range. CLKN n CLK_EXT Ordering Information Speed Package Pb-Free RoHS Compliant Operating Temperature Range Packaging Method CDK2307AILP64 20MSPS QFN-64 Yes Yes -40°C to +85°C Tray CDK2307BILP64 40MSPS QFN-64 Yes Yes -40°C to +85°C Tray CDK2307CILP64 65MSPS QFN-64 Yes Yes -40°C to +85°C Tray CDK2307DILP64 80MSPS QFN-64 Yes Yes -40°C to +85°C Tray CDK2307AITQ64 20MSPS TQFP-64 Yes Yes -40°C to +85°C Tray CDK2307BITQ64 40MSPS TQFP-64 Yes Yes -40°C to +85°C Tray CDK2307CITQ64 65MSPS TQFP-64 Yes Yes -40°C to +85°C Tray CDK2307DITQ64 80MSPS TQFP-64 Yes Yes -40°C to +85°C Tray Moisture sensitivity level for all parts is MSL-2A. ©2009 CADEKA Microcircuits LLC www.cadeka.com Rev 2B Part Number CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters General Description FEATURES Data Sheet Pin Configuration 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 1 48 2 47 3 46 4 45 5 44 6 43 CDK2307 7 42 QFN-64, TQFP-64 8 32 CLK_EXT_EN 31 33 30 16 29 34 CLKN 28 15 27 35 CLKP 26 14 25 36 DVDDCLK 24 13 23 37 DVSSCLK 22 38 12 21 39 11 20 40 19 9 18 CLK_EXT 41 10 17 CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters 64 QFN-64, TQFP-64 Pin Assignments Pin No. Pin Name Description 1, 18, 23 DVDD 2 CM_EXT Digital and I/O-ring pre driver supply voltage, 1.8V 3, 9, 12 AVDD Analog supply voltage, 1.8V 4, 5, 8 AVSS Analog ground 6, 7 IP0, IN0 Analog input Channel 0 (non-inverting, inverting) 10, 11 IP1, IN1 Analog input Channel 1 (non-inverting, inverting) 13 DVSSCLK Clock circuitry ground 14 DVDDCLK Clock circuitry supply voltage, 1.8V 15 CLKP Clock input, non-inverting (Format: LVDS, PECL, CMOS/TTL, Sine Wave) 16 CLKN Clock input, inverting. For CMOS input on CLKP, connect CLKN to ground 17, 64 DVSS Digital circuitry ground 19 CLK_EXT_EN CLK_EXT signal enabled when low (zero). Tristate when high. 20 DFRMT Data format selection. 0: Offset Binary, 1: Two's Complement 21 PD_N 22 OE_N_1 Common Mode voltage output Output Enable Channel 0. Tristate when high. 24, 41, 58 OVDD I/O ring post-driver supply voltage. Voltage range 1.7V to 3.6V. 25, 40, 57 OVSS Ground for I/O ring 26 D1_0 Output Data Channel 1 (LSB, 13-bit output or 1Vpp full scale range ) 27 D1_1 Output Data Channel 1 (LSB, 12-bit output 2Vpp full scale range) 28 D1_2 Output Data Channel 1 29 D1_3 Output Data Channel 1 ©2009 CADEKA Microcircuits LLC Rev 2B Full chip Power Down mode when Low. All digital outputs reset to zero. After chip power up, always apply Power Down mode before using Active Mode to reset chip. www.cadeka.com 2 Data Sheet Pin Assignments (Continued) Pin Name Description 30 D1_4 Output Data Channel 1 31 D1_5 Output Data Channel 1 32 D1_6 Output Data Channel 1 33 D1_7 Output Data Channel 1 34 D1_8 Output Data Channel 1 35 D1_9 Output Data Channel 1 36 D1_10 Output Data Channel 1 37 D1_11 Output Data Channel 1 (MSB for 1Vpp full scale range, see Reference Voltages section) 38 D1_12 Output Data Channel 1 (MSB for 2Vpp full scale range) 39 ORNG_1 Out of Range flag Channel 1. High when input signal is out of range 42 CLK_EXT Output clock signal for data synchronization. CMOS levels. 43 D0_0 Output Data Channel 0 (LSB, 13 bit output or 1Vpp full scale range) 44 D0_1 Output Data Channel 0 (LSB, 12 bit output 2Vpp full scale range) 45 D0_2 Output Data Channel 0 46 D0_3 Output Data Channel 0 47 D0_4 Output Data Channel 0 48 D0_5 Output Data Channel 0 49 D0_6 Output Data Channel 0 50 D0_7 Output Data Channel 0 51 D0_8 Output Data Channel 0 52 D0_9 Output Data Channel 0 53 D0_10 Output Data Channel 0 54 D0_11 Output Data Channel 0 (MSB for 1Vpp full scale range, see Reference Voltages section) 55 D0_12 Output Data Channel 0 (MSB for 2Vpp full scale range) 56 ORNG_0 Out of Range flag Channel 0. High when input signal is out of range. 59 OE_N_0 Output Enable Channel 0. Tristate when low. 60, 61 CM_EXTBC_1, CM_EXTBC_0 62, 63 SLP_N_1, SLP_N_0 CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters Pin No. Bias control bits for the buffer driving pin CM_EXT 00: Off 01: 50uA 10: 500uA 11: 1mA Sleep Mode 00: Sleep Mode 10: Channel 1 active 01: Channel 0 active 11: Both channels active Rev 2B ©2009 CADEKA Microcircuits LLC www.cadeka.com 3 Data Sheet Absolute Maximum Ratings The safety of the device is not guaranteed when it is operated above the “Absolute Maximum Ratings”. The device should not be operated at these “absolute” limits. Adhere to the “Recommended Operating Conditions” for proper device function. The information contained in the Electrical Characteristics tables and Typical Performance plots reflect the operating conditions noted on the tables and plots. Min Max Unit AVDD, AVSS DVDD, DVSS AVSS, DVSSCLK, DVSS, OVSS OVDD, OVSS CKP, CKN, DVSSCLK Analog inputs and outpts (IPx, INx, AVSS) Digital inputs Digital outputs -0.3 -0.3 -0.3 -0.3 -0.3 -0.3 -0.3 -0.3 +2.3 +2.3 +0.3 +3.9 +3.9 +2.3 +3.9 +3.9 V V V V V V V V CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters Parameter Reliability Information Parameter Min Junction Temperature Storage Temperature Range Lead Temperature (Soldering, 10s) -40 -60 Typ Max Unit 85 +150 °C °C J-STD-020 ESD Protection Product Human Body Model (HBM) QFN-64 TQFP-64 2kV 2kV Recommended Operating Conditions Parameter Min Operating Temperature Range -40 Typ Max Unit +85 °C Rev 2B ©2009 CADEKA Microcircuits LLC www.cadeka.com 4 Data Sheet Electrical Characteristics (AVDD = 1.8V, DVDD = 1.8V, DVDDCLK = 1.8V, OVDD = 2.5V, 20/40/65/80MSPS clock, 50% clock duty cycle, -1dBFS 8MHz input signal, 13-bit output, unless otherwise noted) Symbol Parameter Conditions Min Typ Max Units DC Accuracy Guaranteed Offset Error Midscale offset 1 Gain Error Full scale range deviation from typical Gain Matching Gain matching between channels. ±3 sigma value at worst case conditions. ±0.5 %FS DNL Differential Non-Linearity 12-bit level ±0.2 LSB INL Integral Non-Linearity 12-bit level ±0.6 LSB VCMO Common Mode Voltage Output VAVDD/2 V -6 LSB 6 %FS Analog Input VCMI Input Common Mode Analog input common mode voltage Full Scale Range, Normal Differential input voltage range, 2.0 Vpp Full Scale Range, Option Differential input voltage range, 1V (see section Reference Voltages) 1.0 Vpp Input Capacitance Differential input capacitance Bandwidth Input bandwidth, full power 500 AVDD, DVDD Core Supply Voltage Supply voltage to all 1.8V domain pins. See Pin Configuration and Description 1.7 1.8 2.0 V 2.5 3.6 V I/O Supply Voltage Output driver supply voltage (OVDD). Must be higher than or equal to Core Supply Voltage (VOVDD ≥ VDVDD) 1.7 OVDD VFSR VCM -0.1 VCM +0.2 V 2.0 pF MHz Power Supply CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters No Missing Codes Rev 2B ©2009 CADEKA Microcircuits LLC www.cadeka.com 5 Data Sheet Electrical Characteristics - CDK2307A (AVDD = 1.8V, DVDD = 1.8V, DVDDCLK = 1.8V, OVDD = 2.5V, 20MSPS clock, 50% clock duty cycle, -1dBFS 8MHz input signal, 13-bit output, unless otherwise noted) Symbol Parameter Conditions Min Typ Max Units Performance SNR SINAD Signal to Noise Ratio Signal to Noise and Distortion Ratio 72.5 dBFS 72.2 dBFS FIN ≃ FS/2 72.1 dBFS FIN = 20MHz 71.6 dBFS FIN = 2MHz 72.4 dBFS FIN = 8MHz FIN = 8MHz 71.5 72 dBFS FIN ≃ FS/2 71 71.7 dBFS FIN = 20MHz 71.3 dBFS 87 dBc 85 dBc 80 dBc FIN = 20MHz 80 dBc FIN = 2MHz -90 dBc -95 dBc FIN ≃ FS/2 -95 dBc FIN = 20MHz -95 dBc FIN = 2MHz -87 dBc -85 dBc FIN ≃ FS/2 -80 dBc FIN = 20MHz -80 dBc FIN = 2MHz 11.7 bits FIN = 2MHz SFDR HD2 HD3 ENOB XTALK Spurious Free Dynamic Range Second order Harmonic Distortion Third order Harmonic Distortion Effective number of Bits Crosstalk FIN = 8MHz 75 FIN ≃ FS/2 FIN = 8MHz FIN = 8MHz FIN = 8MHz -85 -75 11.7 bits FIN ≃ FS/2 11.5 11.6 bits FIN = 20MHz 11.6 bits Signal crosstalk between channels, FIN1 = 8MHz, FIN0 = 9.9MHz -105 dB Power Supply AIDD Analog Supply Current DIDD Digital Supply Current OIDD Output Driver Supply 11.6 mA Digital core supply 1.8 mA 2.5V output driver supply, sine wave input, FIN = 1MHz 2.9 mA 2.5V output driver supply, sine wave input, FIN = 1MHz, CLK_EXT disabled 2.4 mA Analog Power Dissipation mW Digital Power Dissipation 9.2 mW Total Power Dissipation OVDD = 2.5V, 5pF load on output bits, FIN = 1MHz, CLK_EXT disabled 30.1 mW 9.9 µW Sleep Mode 1 Power Dissipation, Sleep mode one channel 20.5 mW Sleep Mode 2 Power Dissipation, Sleep mode both channels 9.2 mW Power Down Dissipation Rev 2B 20.9 OVDD = 2.5V, 5pF load on output bits, FIN = 1MHz, CLK_EXT disabled Clock Inputs Max. Conversion Rate Min. Conversion Rate ©2009 CADEKA Microcircuits LLC 20 MSPS 15 MSPS www.cadeka.com CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters FIN = 2MHz 6 Data Sheet Electrical Characteristics - CDK2307B (AVDD = 1.8V, DVDD = 1.8V, DVDDCLK = 1.8V, OVDD = 2.5V, 40MSPS clock, 50% clock duty cycle, -1dBFS 8MHz input signal, 13-bit output, unless otherwise noted) Symbol Parameter Conditions Min Typ Max Units Performance SNR SINAD Signal to Noise Ratio Signal to Noise and Distortion Ratio FIN = 8MHz 71.9 FIN ≃ FS/2 HD2 HD3 ENOB XTALK Spurious Free Dynamic Range Second order Harmonic Distortion Third order Harmonic Distortion Effective number of Bits Crosstalk dBFS 72.7 dBFS 72 dBFS FIN = 30MHz 70.8 dBFS FIN = 2MHz 71.7 dBFS FIN = 8MHz 72.1 dBFS FIN ≃ FS/2 71 71.5 dBFS FIN = 30MHz 71.2 dBFS 81 dBc 81 dBc 80 dBc FIN = 30MHz 80 dBc FIN = 2MHz -90 dBc -95 dBc FIN ≃ FS/2 -95 dBc FIN = 30MHz -90 dBc FIN = 2MHz -81 dBc -81 dBc FIN ≃ FS/2 -80 dBc FIN = 30MHz -80 dBc FIN = 2MHz 11.6 bits FIN = 2MHz SFDR 72.5 FIN = 8MHz 75 FIN ≃ FS/2 FIN = 8MHz FIN = 8MHz FIN = 8MHz -85 -75 11.7 bits FIN ≃ FS/2 11.5 11.6 bits FIN = 30MHz 11.5 bits Signal crosstalk between channels, FIN1 = 8MHz, FIN0 = 9.9MHz -100 dB Power Supply AIDD Analog Supply Current DIDD Digital Supply Current OIDD Output Driver Supply 21.1 mA Digital core supply 3.3 mA 2.5V output driver supply, sine wave input, FIN = 1MHz 5.3 mA 2.5V output driver supply, sine wave input, FIN = 1MHz, CLK_EXT disabled 4.4 mA Analog Power Dissipation mW Digital Power Dissipation 16.9 mW Total Power Dissipation OVDD = 2.5V, 5pF load on output bits, FIN = 1MHz, CLK_EXT disabled 54.9 mW 9.7 µW Sleep Mode 1 Power Dissipation, Sleep mode one channel 36.1 mW Sleep Mode 2 Power Dissipation, Sleep mode both channels 14.2 mW Power Down Dissipation Rev 2B 38.0 OVDD = 2.5V, 5pF load on output bits, FIN = 1MHz, CLK_EXT disabled Clock Inputs Max. Conversion Rate Min. Conversion Rate ©2009 CADEKA Microcircuits LLC 40 MSPS 20 MSPS www.cadeka.com CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters FIN = 2MHz 7 Data Sheet Electrical Characteristics - CDK2307C (AVDD = 1.8V, DVDD = 1.8V, DVDDCLK = 1.8V, OVDD = 2.5V, 65MSPS clock, 50% clock duty cycle, -1dBFS 8MHz input signal, 13-bit output, unless otherwise noted) Symbol Parameter Conditions Min Typ FIN = 8MHz 71.6 Max Units Performance Signal to Noise Ratio dBFS 71.8 dBFS FIN ≃ FS/2 71.5 dBFS FIN = 40MHz 70.4 dBFS 71.7 dBFS FIN = 20MHz 71.7 dBFS FIN ≃ FS/2 71.7 dBFS 70 dBFS FIN = 8MHz SINAD Signal to Noise and Distortion Ratio 70.5 FIN = 40MHz FIN = 8MHz SFDR Spurious Free Dynamic Range 81 dBc FIN = 20MHz 75 84 dBc FIN ≃ FS/2 79 dBc FIN = 40MHz 77 dBc -95 dBc FIN = 20MHz -95 dBc FIN ≃ FS/2 -95 dBc FIN = 40MHz -95 dBc -81 dBc FIN = 20MHz -84 dBc FIN ≃ FS/2 -79 dBc FIN = 40MHz -79 dBc 11.6 bits FIN = 20MHz 11.6 bits FIN ≃ FS/2 11.5 bits FIN = 40MHz 11.3 bits Signal crosstalk between channels, FIN1 = 8MHz, FIN0 = 9.9MHz -95 dB FIN = 8MHz HD2 Second order Harmonic Distortion FIN = 8MHz HD3 Third order Harmonic Distortion FIN = 8MHz ENOB XTALK Effective number of Bits Crosstalk -85 -75 11.4 Power Supply AIDD Analog Supply Current DIDD Digital Supply Current OIDD Output Driver Supply 32.8 mA Digital core supply 5.0 mA 2.5V output driver supply, sine wave input, FIN = 1MHz 8.2 mA 2.5V output driver supply, sine wave input, FIN = 1MHz, CLK_EXT disabled 6.6 mA Analog Power Dissipation mW Digital Power Dissipation 25.5 mW Total Power Dissipation OVDD = 2.5V, 5pF load on output bits, FIN = 1MHz, CLK_EXT disabled 84.5 mW 9.3 µW Sleep Mode 1 Power Dissipation, Sleep mode one channel 55.3 mW Sleep Mode 2 Power Dissipation, Sleep mode both channels 20.4 mW Power Down Dissipation Rev 2B 59.0 OVDD = 2.5V, 5pF load on output bits, FIN = 1MHz, CLK_EXT disabled Clock Inputs Max. Conversion Rate Min. Conversion Rate ©2009 CADEKA Microcircuits LLC 65 MSPS 40 MSPS www.cadeka.com CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters SNR 72.6 FIN = 20MHz 8 Data Sheet Electrical Characteristics - CDK2307D (AVDD = 1.8V, DVDD = 1.8V, DVDDCLK = 1.8V, OVDD = 2.5V, 80MSPS clock, 50% clock duty cycle, -1dBFS 8MHz input signal, 13-bit output, unless otherwise noted) Symbol Parameter Conditions Min FIN = 8MHz 70.4 Typ Max Units Performance Signal to Noise Ratio dBFS 71.7 dBFS FIN = 30MHz 71.2 dBFS FIN ≃ FS/2 70.7 dBFS 70.5 dBFS FIN = 20MHz 70.5 dBFS FIN = 30MHz 70.4 dBFS FIN ≃ FS/2 70.3 dBFS FIN = 8MHz SINAD Signal to Noise and Distortion Ratio FIN = 8MHz SFDR Spurious Free Dynamic Range 69.5 77 dBc FIN = 20MHz 74 78 dBc FIN = 30MHz 78 dBc FIN ≃ FS/2 78 dBc -95 dBc -90 dBc FIN = 30MHz -90 dBc FIN ≃ FS/2 -85 dBc -77 dBc -78 dBc FIN = 30MHz -78 dBc FIN ≃ FS/2 -78 dBc 11.4 bits FIN = 20MHz 11.4 bits FIN = 30MHz 11.4 bits FIN ≃ FS/2 11.4 bits Signal crosstalk between channels, FIN1 = 8MHz, FIN0 = 9.9MHz -95.0 dB FIN = 8MHz HD2 Second order Harmonic Distortion FIN = 20MHz FIN = 8MHz HD3 Third order Harmonic Distortion XTALK Effective number of Bits Crosstalk -74 FIN = 20MHz FIN = 8MHz ENOB -80 11.3 Power Supply AIDD Analog Supply Current DIDD Digital Supply Current OIDD Output Driver Supply 39.7 mA Digital core supply 6.0 mA 2.5V output driver supply, sine wave input, FIN = 1MHz 9.4 mA 2.5V output driver supply, sine wave input, FIN = 1MHz, CLK_EXT disabled 7.7 mA Analog Power Dissipation mW Digital Power Dissipation 30 mW Total Power Dissipation OVDD = 2.5V, 5pF load on output bits, FIN = 1MHz, CLK_EXT disabled 101.5 mW 9.1 µW Sleep Mode 1 Power Dissipation, Sleep mode one channel 66.4 mW Sleep Mode 2 Power Dissipation, Sleep mode both channels 24.1 mW Power Down Dissipation Rev 2B 71.5 OVDD = 2.5V, 5pF load on output bits, FIN = 1MHz, CLK_EXT disabled Clock Inputs Max. Conversion Rate Min. Conversion Rate ©2009 CADEKA Microcircuits LLC 80 MSPS 65 MSPS www.cadeka.com CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters SNR 72 FIN = 20MHz 9 Data Sheet Digital and Timing Electrical Characteristics (AVDD = 1.8V, DVDD = 1.8V, DVDDCLK = 1.8V, OVDD = 2.5V, 50 MSPS clock, 50% clock duty cycle, -1 dBFS input signal, 5pF capacitive load, unless otherwise noted) Symbol Parameter Conditions Min Typ Max Units 80 % high Clock Inputs 20 Compliance Input Range CMOS, LVDS, LVPECL, Sine Wave Differential input swing 400 Differential input swing, sine wave clock input 1.6 mVpp Vpp Input Common Mode Voltage Keep voltages within ground and voltage of OVDD 0.3 VOVDD -0.3 V Input Capacitance Differential TPD Start Up Time Active Mode From Power Down Mode to Active Mode 900 TSLP Start Up Time Mode From Sleep Mode to Active 20 TOVR Out Of Range Recovery Time TAP Aperture Delay 0.8 ns εRMS Aperture Jitter <0.5 psrms TLAT Pipeline Delay 12 clk cycles TD Output Delay (see timing diagram) 5pF load on output bits 3 10 ns TDC Output Delay (see timing diagram) Relative to CLK_EXT 1 6 ns VOVDD ≥ 3.0V 2 2 pF Timing 1 clk cycles clk cycles clk cycles Logic Inputs VHI High Level Input Voltage VOVDD = 1.7V – 3.0V V 0.8 • VOVDD V VOVDD ≥ 3.0V 0 0.8 V VOVDD = 1.7V – 3.0V 0 0.2 • VOVDD V VLI Low Level Input Voltage IHI High Level Input Leakage Current -10 10 µA ILI Low Level Input Leakage Current -10 10 µA CI Input Capacitance 3 pF Logic Outputs VHO High Level Output Voltage VLO Low Level Output Voltage CL Max Capacitive Load VOVDD-0.1 V Post-driver supply voltage equal to pre-driver supply voltage VOVDD = VDVDD Post-driver supply voltage above 2.25V (1) 0.1 V 5 pF 10 pF Note: (1) The outputs will be functional with higher loads. However, it is recommended to keep the load on output data bits as low as possible to keep dynamic currents and resulting switching noise at a minimum. CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters Duty Cycle Rev 2B ©2009 CADEKA Microcircuits LLC www.cadeka.com 10 Data Sheet +F1 +F4 +F +F2 + +F0 CLK_EXT Figure 1. Timing Diagram Recommended Usage DC-Coupling Analog Input Figure 3 shows a recommended configuration for DCcoupling. Note that the common mode input voltage must be controlled according to specified values. Preferably, the CM_EXT output should be used as a reference to set the common mode voltage. The analog input to the CDK2307 is done through a switched capacitor track-and-hold amplifier optimized for differential operation. Operation at mid supply common mode voltage is recommended even if performance will be good for the ranges specified. The CM_EXT pin provides a voltage suitable for a common mode voltage reference. The internal buffer for the CM_EXT voltage can be switched off, and driving capabilities can be changed by using the CM_EXTBC control input. 43Ω 33pF 43Ω Rev 2B Figure 2 shows a simplified drawing of the input network. The signal source must have sufficiently low output impedance to charge the sampling capacitors within one clock cycle. A small external resistor (e.g. 22Ω) in series with each input is recommended as it helps reducing transient currents and dampens ringing behavior. A small differential shunt capacitor at the chip side of the resistors may be used to provide dynamic charging currents and may improve performance. The resistors form a low pass filter with the capacitor, and values must therefore be determined by requirements for the application. The input amplifier could be inside a companion chip or it could be a dedicated amplifier. Several suitable single ended to differential driver amplifiers exist in the market. The system designer should make sure the specifications of the selected amplifier is adequate for the total system, and that driving capabilities comply with the CDK2307 input specifications. Figure 3. DC-Coupled Input Detailed configuration and usage instructions must be found in the documentation of the selected driver. AC-Coupling Figure 2. Input Configuration ©2009 CADEKA Microcircuits LLC A signal transformer or series capacitors can be used to make an AC-coupled input network. Figure 4 shows a recommended configuration using a transformer. Make sure that a transformer with sufficient linearity is selected, www.cadeka.com CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters N-13 11 Data Sheet If the input signal is traveling a long physical distance from the signal source to the transformer (for example a long cable), kick-backs from the ADC will also travel along this distance. If these kick-backs are not terminated properly at the source side, they are reflected and will add to the input signal at the ADC input. This could reduce the ADC performance. To avoid this effect, the source must effectively terminate the ADC kick-backs, or the traveling distance should be very short. If this problem could not be avoided, the circuit in Figure 6 can be used. Note that startup time from Sleep Mode and Power Down Mode will be affected by this filter as the time required to charge the series capacitors is dependent on the filter cut-off frequency. If the input signal has a long traveling distance, and the kick-backs from the ADC not are effectively terminated at the signal source, the input network of Figure 6 can be used. The configuration is designed to attenuate the kickback from the ADC and to provide an input impedance that looks as resistive as possible for frequencies below Nyquist. Values of the series inductor will however depend on board design and conversion rate. In some instances a shunt capacitor in parallel with the termination resistor (e.g. 33pF) may improve ADC performance further. This capacitor attenuate the ADC kick-back even more, and minimize the energy traveling towards the source. However, the impedance match seen into the transformer will become worse. 120nH 33Ω 1:1 33Ω optional RT 47Ω RT 68Ω 220Ω pF 120nH 33Ω 33Ω Figure 4. Transformer-Coupled Input Ω pF Ω Figure 5. AC-Coupled Input ©2009 CADEKA Microcircuits LLC Clock Input And Jitter Considerations Typically high-speed ADCs use both clock edges to generate internal timing signals. In the CDK2307 only the rising edge of the clock is used. Hence, input clock duty cycles between 20% and 80% are acceptable. The input clock can be supplied in a variety of formats. The clock pins are AC-coupled internally, and hence a wide common mode voltage range is accepted. Differential clock sources such as LVDS, LVPECL or differential sine wave can be connected directly to the input pins. For CMOS inputs, the CLKN pin should be connected to ground, and the CMOS clock signal should be connected to CLKP. For differential sine wave clock input the amplitude must be at least ±800mVpp. www.cadeka.com 12 Rev 2B Figure 5 shows AC-coupling using capacitors. Resistors from the CM_EXT output, RCM, should be used to bias the differential input signals to the correct voltage. The series capacitor, CI, form the high-pass pole with these resistors, and the values must therefore be determined based on the requirement to the high-pass cut-off frequency. Figure 6. Alternative Input Network CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters and that the bandwidth of the transformer is appropriate. The bandwidth should exceed the sampling rate of the ADC with at least a factor of 10. It is also important to keep phase mismatch between the differential ADC inputs small for good HD2 performance. This type of transformer coupled input is the preferred configuration for high frequency signals as most differential amplifiers do not have adequate performance at high frequencies. Magnetic coupling between the transformers and PCB traces may impact channel crosstalk, and must hence be taken into account during PCB layout. Data Sheet The quality of the input clock is extremely important for high-speed, high-resolution ADCs. The contribution to SNR from clock jitter with a full scale signal at a given frequency is shown in equation 1. • π • FIN • εt) where FIN is the signal frequency, and εt is the total rms jitter measured in seconds. The rms jitter is the total of all jitter sources including the clock generation circuitry, clock distribution and internal ADC circuitry. For applications where jitter may limit the obtainable performance, it is of utmost importance to limit the clock jitter. This can be obtained by using precise and stable clock references (e.g. crystal oscillators with good jitter specifications) and make sure the clock distribution is well controlled. It might be advantageous to use analog power and ground planes to ensure low noise on the supplies to all circuitry in the clock distribution. It is of utmost importance to avoid crosstalk between the ADC output bits and the clock and between the analog input signal and the clock since such crosstalk often results in harmonic distortion. Note that the out of range flags (ORNG) will behave differently for 12-bit and 13-bit output. For 13-bit output ORNG will be set when digital output data are all ones or all zeros. For 12-bit output the ORNG flags will be set when all twelve bits are zeros or ones and when the thirteenth bit is equal to the rest of the bits. The CDK2307 employs digital offset correction. This means that the output code will be 4096 with the positive and negative inputs shorted together(zero differential). However, small mismatches in parasitics at the input can cause this to alter slightly. The offset correction also results in possible loss of codes at the edges of the full scale range. With “NO” offset correction, the ADC would clip in one end before the other, in practice resulting in code loss at the opposite end. With the output being centered digitally, the output will clip, and the out of range flags will be set, before max code is reached. When out of range flags are set, the code is forced to all ones for over-range and all zeros for under-range. The jitter performance is improved with reduced rise and fall times of the input clock. Hence, optimum jitter performance is obtained with LVDS or LVPECL clock with fast edges. CMOS and sine wave clock inputs will result in slightly degraded jitter performance. Data Format Selection If the clock is generated by other circuitry, it should be retimed with a low jitter master clock as the last operation before it is applied to the ADC clock input. The data outputs can be used in three different configurations. Digital Outputs The timing is described in the Timing Diagram section. Note that the load or equivalent delay on CLK_EXT always should be lower than the load on data outputs to ensure sufficient timing margins. ©2009 CADEKA Microcircuits LLC Normal mode: All 13-bits are used. MSB is Dx_12 and LSB is Dx_0. This mode gives optimum performance due to reduced quantization noise. 12-bit mode: The LSB is left unconnected such that only 12 bits are used. MSB is Dx_12 and LSB is Dx_1. This mode gives slightly reduced performance, due to increased quantization noise. Reduced full scale range mode: The full scale range is reduced from 2Vpp to 1Vpp which is equivalent to 6dB gain in the ADC frontend. MSB is Dx_11 and LSB is Dx_0. Note that the codes will wrap around when exceeding the full scale range, and that out of range bits should be used to clamp output data. See section Reference Voltages for details. This mode gives slightly reduced performance. www.cadeka.com 13 Rev 2B Digital output data are presented in a parallel CMOS form. The voltage on the OVDD pin sets the levels of the CMOS outputs. The output drivers are dimensioned to drive a wide range of loads for OVDD above 2.25V, but it is recommended to minimize the load to ensure as low transient switching currents and resulting noise as possible. In applications with a large fanout or large capacitive loads, it is recommended to add external buffers located close to the ADC chip. The output data are presented on offset binary form when DFRMT is low (connect to OVSS). Setting DFRMT high (connect to OVDD) results in 2’s complement output format. Details are shown in Table 1 on page 14. CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters SNRjitter = 20 • log (2 The digital outputs can be set in tristate mode by setting the OE_N signal high. Data Sheet Table 1: Data Format Description for 2Vpp Full Scale Range Output Data: Dx_12 : Dx_0 (DFRMT = 0, offset binary) (DFRMT = 1, 2’s complement) 1.0 V 1 1111 1111 1111 0 1111 1111 1111 +0.24mV 1 0000 0000 0000 0 0000 0000 0000 -0.24mV 0 1111 1111 1111 1 1111 1111 1111 -1.0V 0 0000 0000 0000 1 0000 0000 0000 Reference Voltages Operational Modes The reference voltages are internally generated and buffered based on a bandgap voltage reference. No external decoupling is necessary, and the reference voltages are not available externally. This simplifies usage of the ADC since two extremely sensitive pins, otherwise needed, are removed from the interface. The operational modes are controlled with the PD_N and SLP_N pins. If PD_N is set low, all other control pins are overridden and the chip is set in Power Down mode. In this mode all circuitry is completely turned off and the internal clock is disabled. Hence, only leakage current contributes to the Power Down Dissipation. The startup time from this mode is longer than for other idle modes as all references need to settle to their final values before normal operation can resume. If a lower full scale range is required the 13-bit output word provides sufficient resolution to perform digital scalingwith an equivalent impact on noise compared to adjusting the reference voltages. A simple way to obtain 1.0Vpp input range with a 12-bit output word is shown in the table on page 10. Note that only 2‘s complement output data are available in this mode and that out of range conditions must be determined based on a two bit output. The output code will wrap around when the code goes outside the full scale range. The out of range bits should be used to clamp the output data for overrange conditions. The SLP_N bus can be used to power down each channel independently, or to set the full chip in Sleep Mode. In this mode internal clocking is disabled, but some low bandwidth circuitry is kept on to allow for a short startup time. However, Sleep Mode represents a significant reduction in supply current, and it can be used to save power even for short idle periods. The input clock could be kept running in all idle modes. However, even lower power dissipation is possible in Power Down mode if the input clock is stopped. In this case it is important to start the input clock prior to enabling active mode. Table 2: Data Format Description for 1Vpp Full Scale Range Output data: Dx_11: Dx_0 (DFRMT = 0) > 0.5V 0111 1111 1111 0.5V 0111 1111 1111 0111 1111 1111 +0.24mV 0000 0000 0000 0000 0000 0000 -0.24mV 1111 1111 1111 1111 1111 1111 -0.5V 1000 0000 0000 1000 0000 0000 < -0.5V 1000 0000 0000 (2’s Complement) ©2009 CADEKA Microcircuits LLC Out of Range (Use Logical AND Function for &) Dx_12 = 1 & Dx_11 = 1 Dx_12 = 0 & Dx_11 = 0 Output Data: Dx_11: Dx_0 (DFRMT = 1) (2’s Complement) 0111 1111 1111 1000 0000 0000 Out of Range (Use Logical AND Function for &) D_12 = 0 & D_11 = 1 Rev 2B Differential Input Voltage (IPx - INx) Dx_12 = 1 & Dx_11 = 0 www.cadeka.com CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters Output data: Dx_12 : Dx_0 Differential Input Voltage (IPx - INx) 14 Data Sheet Mechanical Dimensions QFN-64 Package aaa C A A ccc C D1 aaa C B A1 E Symbol A A1 A2 A3 b D D1 D2 E E1 E2 F G L e θ1 E1 aaa bbb ccc Pin 1 ID 0.05 Dia. Inches Typ – 0.0004 0.026 0.008 REF 0.010 0.354 BSC 0.354 BSC 0.205 0.354 BSC 0.344 BSC 0.205 Min – 0.00 – 0.008 0.197 0.197 0.05 0.0096 0.012 0° Max 0.035 0.002 0.028 Min – 0.00 – 0.012 0.2 0.213 5.0 0.213 5.0 Millimeters Typ – 0.01 0.65 0.2 REF 0.25 9.00 BSC 8.75 BSC 5.2 9.00 BSC 8.75 BSC 5.2 – – 1.3 – 0.0168 0.024 0.24 0.42 0.016 0.020 0.3 0.4 0.020 BSC 0.50 BSC – 12° 0° – Tolerance of Form and Position 0.10 0.004 0.10 0.004 0.05 0.002 Max 0.9 0.05 0.7 0.30 5.4 5.4 – 0.6 0.5 12° NOTES: 1. All dimensions are in millimeters. 2. Die thickness allowable is 0.305mm maximum (.012 inches maximum) 3. Dimensioning & tolerances conform to ASME y14.5m. -1994. 1.14 bbb C B B C bbb C A 1.14 5. The pin #1 identifier must be placed on the top surface of the package by using indentation mark or other feature of package body. 6. Exact shape and size of this feature is optional. 7. Package warpage max 0.08mm. SIDE VIEW 9. Applied only to terminals. 10. Package corners unless otherwise specipied are r0.175±0.025mm. F D2 0.45 4. Dimension applies to plated terminal and is measured between 0.20 and 0.25mm from terminal tip. 8. Applied for exposed pad and terminals. Exclude embedding part of exposed pad from measuring. TOP VIEW Pin 1 ID Dia. 0.20 seating plane θ1 G E2 L e b 0.10 M C A B L BOTTOM VIEW CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters A A2 A3 D Rev 2B ©2009 CADEKA Microcircuits LLC www.cadeka.com 15 Data Sheet Mechanical Dimensions (Continued) TQFP-64 Package TOP VIEW SIDE VIEW Min – 0.002 0.037 0.003 0.003 0° 0° 11° 11° 0.004 0.018 0.008 0.007 Inches Typ – – 0.039 0.472 BSC 0.393 BSC 0.472 BSC 0.393 BSC – – 3.5° – 12° 12° – 0.24 0.039 REF – 0.008 0.020 BSC 0.295 0.295 0.008 0.008 0.003 0.003 Max 0.047 0.006 0.041 Min – 0.05 0.95 0.008 – 7° – 13° 13° 0.008 0.030 0.08 0.08 0° 0° 11° 11° 0.09 0.45 – 0.011 0.20 0.17 Millimeters Typ – – 1.00 12.00 BSC 10.00 BSC 12.00 BSC 10.00 BSC – – 3.5° – 12° 12° 0.20 0.75 1.00 REF – 0.20 0.520 BSC 7.50 7.50 0.20 0.20 0.08 0.08 Max 1.2 0.15 1.05 0.20 – 7° – 13° 13° – 0.27 NOTES: 1. Dimensions D1 and E1 do not include mold protrusion. Allowable protrusion is 0.25mm per side. D1 and E1 are maxmum plastic body size dimensions including mold mismatch. 2. Dimension b does not include dambar protrusion. Allowable dambar protrusion shall not cause the lead width to exceed the maximum b dimension by more than 0.08mm. 3. Dambar can not be located on the lower radius or the foot. Minimum space between protrusion and an adjacent lead is 0.07mm for 0.4mm and 0.5mm pitch packages. DETAIL SIDE VIEW CDK2307 Dual, 20/40/65/80MSPS, 12/13-bit Analog-to-Digital Converters Symbol A A1 A2 D D1 E E1 R2 R1 θ θ1 θ2 θ3 c L L1 S b e D2 E2 aaa bbb ccc ddd Rev 2B For additional information regarding our products, please visit CADEKA at: cadeka.com CADEKA Headquarters Loveland, Colorado T: 970.663.5452 T: 877.663.5452 (toll free) CADEKA, the CADEKA logo design, COMLINEAR and the COMLINEAR logo design are trademarks or registered trademarks of CADEKA Microcircuits LLC. All other brand and product names may be trademarks of their respective companies. CADEKA reserves the right to make changes to any products and services herein at any time without notice. CADEKA does not assume any responsibility or liability arising out of the application or use of any product or service described herein, except as expressly agreed to in writing by CADEKA; nor does the purchase, lease, or use of a product or service from CADEKA convey a license under any patent rights, copyrights, trademark rights, or any other of the intellectual property rights of CADEKA or of third parties. Copyright ©2009 by CADEKA Microcircuits LLC. All rights reserved. A m p l i fy t h e H u m a n E x p e r i e n c e