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 CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs n TTL/CMOS/PECL input logic compatible n High conversion rate: 250 MSPS n Single +5V power supply n Very low power dissipation: 310mW n 220MHz full power bandwidth n Power-down mode n +3.0V/+5.0V (LVCMOS) digital output The CDK1300 is a high-speed, 8-bit analog-to-digital converter implemented in an advanced BiCMOS process. An advanced folding and interpolating architecture provides both a high conversion rate and very low power dissipation of only 310mW. The analog inputs can be operated in either single-ended or differential input mode. A 2.5V common mode reference is provided on chip for the single-ended input mode to minimize external components. logic compatibility n The CDK1300 digital outputs are demuxed (double-wide) with both dualchannel and single-channel selectable output modes. Demuxed mode supports either parallel aligned or interleaved data output. The output logic is both +3.0V and +5.0V compatible. The CDK1300 is available in a 44-lead TQFP surface mount package over the industrial temperature range of -40°C to +85°C. Single/demuxed output ports selectable Applications n RGB video processing n Digital communications n High-speed instrumentation n Digital Sampling Oscilloscopes (DSO) n Projection display systems Block Diagram CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs General Description features REV 1A Ordering Information Part Number Package Pb-Free RoHS Compliant Operating Temperature Range Packaging Method CDK1300ITQ44 TQFP-44 Yes Yes -40°C to +85°C Rail CDK1300ITQ44_Q TQFP-44 No No -40°C to +85°C Rail Moisture sensitivity level for all parts is MSL-1. ©2008 CADEKA Microcircuits LLC www.cadeka.com Data Sheet Pin Configuration TQFP-44 Pin Assignments Pin Name 40 VIN+ Description Non-inverted analog input; nominally 1Vpp; 100k pullup to Vcc and 100k pulldown to AGND, internally 39 VIN- Inverted analog input; nominally 1Vpp; 100k pullup to Vcc and 100k pulldown to AGND, internally 16-9 DA0–DA7 Data output bank A; 3V/5V LVCMOS compatible 19-26 DB0–DB7 Data output bank B; 3V/5V LVCMOS compatible 28 DCLKOUT Non-inverted data output clock; 3V/5V LVCMOS compatible 27 DCLKOUT Inverted data output clock; 3V/5V LVCMOS compatible 4 CLK Non-inverted clock input pin; 100k pulldown to AGND, internally 3 CLK Inverted clock input pin; 17.5k pullup to Vcc and 7.5k pulldown to AGND, internally 5 RESET RESET synchronizes the data sampling and data output bank relationship when in dual channel mode (DMODE1 = 0); 100k pulldown to AGND, internally 6 RESET Inverted RESET input pin; 17.5k pullup to Vcc and 7.5 pulldown to AGND, internally REV 1A Pin No. Internally: 100k pulldown to AGND on DMODE1 50k pullup to Vcc on DMODE2 32, 31 DMODE1,2 Data output mode pins: DMODE1 = 0, DMODE2 = 0: parallel dual channel output DMODE1 = 0, DMODE2 = 1: interleaved dual channel output DMODE1 = 1, DMODE2 = x: single channel data output on bank a (125 MSPS max) 2 PD Power-Down pin; PD = 1 for Power-Down mode. Outputs set to high impedance in Power-Down mode; 100k pulldown to AGND, internally 37 VCM 2.5V common mode voltage reference output 35, 36, 42, 43 AVCC +5V analog supply 7, 17, 30 OVDD +3V/+5V digital output supply 1, 33, 34, 38, 41, 44 AGND Analog ground 8, 18, 29 DGND Digital ground ©2008 CADEKA Microcircuits LLC www.cadeka.com CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs CDK1300 2 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. Supply Voltage AVCC OVDD Input Voltages Analog inputs Digital inputs Min -0.5V -0.5V Max Unit +6 +6 V V Vcc +0.5V Vcc +0.5V V V CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs Parameter Reliability Information Parameter Min Storage Temperature Range -65 Typ Max Unit +125 °C Max Unit +85 °C Recommended Operating Conditions Parameter Min Operating Temperature Range -40 Typ REV 1A ©2008 CADEKA Microcircuits LLC www.cadeka.com 3 Data Sheet Electrical Characteristics (TA = TMin to TMax, AVCC= +5V, OVDD = +5V, ƒclk = 250MHz, 50% duty cycle, ƒIN = 70MHz, dual channel mode; unless otherwise noted) Symbol Parameter Conditions Min Resolution Typ Max Units bits DLE ILE Differential Linearity Error +25°C, ƒIN = 1KHz -0.7/1.05 LSB -40°C to +85°C, ƒIN = 1KHz Integral Linearity Error No Missing Codes -0.95/+1.5 LSB +25°C, ƒIN = 1KHz ±1.7 LSB -40°C to +85°C, ƒIN = 1KHz ±2.25 LSB @250 MSPS, ƒIN = 1KHz Guaranteed Analog Input Input Voltage Range VCM PSRR with respect to VIN- ±470 Input Common Mod 2.3 (2) 2.5 mVpp 2.0 V Input Bias Current +25°C 10 µA Input Resistance +25°C 50 kΩ Input Capacitance +25°C Input Bandwidth +25°C (-3dB of FS) Gain Error 4 pF 220 MHz +25°C 2 % Offset Error +25°C ±10 mV Offset Power Supply Rejection Ratio AVcc = 5V ±0.25V 0.5 mV/V Timing Characteristics 250 Conversion Rate(1) tpd1 tap Output Delay (Clock-to-Data) (2) -40°C to +85°C 6 MSPS 8 10.5 ns ps/°C Aperture Delay Time 0.5 ns Aperture Jitter Time 2.0 ps-RMS Single Channel Mode 2.5 Cycle Demuxed Interleaved Mode 2.5 Cycle Channel B 2.5 Cycle Channel A 3.5 Cycle Pipeline Delay (Latency) Demuxed Parallel Mode CLK to DCLKOUT Delay Time tpd2 Single Channel Mode(2) tpd3 Dual Channel Mode (2) 4 6 7 ns 5.3 6.16 7.8 ns 5.8 6.4 Bits Dynamic Performance ENOB SNR THD SINAD Effective Number of Bits Signal-to-Noise Ratio Total Harmonic Distortion Signal-to-Noise and Distortion ƒIN = 70MHz, +25°C(1) ƒIN = 70MHz, -40°C to +85°C 5.5 6.0 Bits ƒIN = 70MHz, +25°C(1) 42 43 dB ƒIN = 70MHz, -40°C to +85°C(2) 36 40 dB ƒIN = 70MHz, +25°C (2) (1) ƒIN = 70MHz, -40°C to +85°C(2) ƒIN = 70MHz , +25°C(1) ƒIN = 70MHz, -40°C to +85°C (2) -43 -40 dB -42 -37 dB 37 40 dB 35 38 dB Notes: 1. 100% production tested at +25°C. 2. Parameter is guaranteed (but not tested) by design and characterization data. ©2008 CADEKA Microcircuits LLC www.cadeka.com 4 22 REV 1A Output Delay Tempco CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs 8 DC Performance Data Sheet Electrical Characteristics (TA = TMin to TMax, AVCC= +5V, OVDD = +5V, ƒclk = 250MHz, 50% duty cycle, ƒIN = 70MHz, dual channel mode; unless otherwise noted) Symbol Parameter Conditions Min Typ Max Units 5.0 5.25 V 5.25 V Power Supply Requirements Analog Voltage Supply(2) 4.75 OVDD Digital Voltage Supply(2) 2.75 AVcc Current (1) Power Dissipation(1) with Internal Voltage Reference 62 70 mA 310 350 mW 2.5 2.55 Common Mode Reference Output Voltage(1) 2.45 Voltage Tempco Output Impedance PSRR IOUT = ±50µA Power Supply Rejection Ratio V 100 ppm/°C 1 kΩ 63 mV/V Clock and Reset Inputs (Differential and Single-Ended) VDIFF Differental Signal Amplitude(1) 400 VIHD Differental High Input Voltage VILD Differental Low Input Voltage(2) VCMD mVpp 1.4 5 V 0 3.9 V Differental Common Mode Input(2) 1.2 4.1 V VIH Single-Ended High Input Voltage 1.8 VIL Single-Ended Low Input Voltage(2) IIH High Input Current(1) VID = 1.5V -100 IIL Low Input Current(1) VID = 1.5V -100 (2) (2) V 1.2 V 20 +100 µA 20 +100 µA Power Down and Mode Control Inputs (Single-Ended) High Input Voltage(2) 2.0 AVcc V Low Input Voltage(2) 0 1.0 V Max Input Current Low (1) Max Input Current High <4.0V(1) -100 10 +100 µA -100 10 +100 µA Digital Outputs Logic “1“ Voltage(1) IOH = -0.5mA Logic “0“ Voltage(1) IOL = +1.6mA 0.13 OVDD = 3V, 10pF load 3.5 ns OVDD = 5V, 10pF load 2.0 ns OVDD = 3V, 10pF load 1.3 ns OVDD = 5V, 10pF load 0.7 ns V TR/TF DCLK V 0.2 REV 1A TR/TF Data OVDD-2.0 OVDD-0.06 Notes: 1. 100% production tested at +25°C. 2. Parameter is guaranteed (but not tested) by design and characterization data. ©2008 CADEKA Microcircuits LLC www.cadeka.com CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs AVcc 5 Data Sheet Typical Performance Characteristics (TA = TMin to TMax, AVCC= +5V, OVDD = +5V, ƒclk = 250MHz, 50% duty cycle, ƒIN = 70MHz, dual channel mode; unless otherwise noted) AC Performance vs. Temperature AC Performance vs. Temperature SFDR, SNR, –THD, SINAD (dB) 60 in = 70MHz 55 50 SFDR 45 –THD SNR 40 SINAD 35 30 -40 -20 0 20 40 60 80 60 in = 70MHz 55 50 SFDR 45 SNR –THD 40 SINAD 35 30 100 0 50 Temperature (°C) 150 200 250 300 AVcc Current Power Down vs. Temp. 75 3.0 70 2.8 AVcc (mA) 65 60 55 2.6 2.4 2.2 50 45 100 Sample Rate (MSPS) AVcc Current vs. Temperature AVCC Current (mA) CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs SFDR, SNR, –THD, SINAD (dB) -20 0 20 40 60 80 2.0 100 -40 -20 20 40 60 80 100 Temperature (°C) Temperature (°C) 0 REV 1A -40 Voltage Offset Error vs. Temperature Percent Gain Error vs. Temperature 6.0 1.06 4.0 1.05 2.0 1.04 Gain (%) mV 0 1.03 -2.0 1.02 -4.0 1.01 -6.0 -40 -20 0 20 40 60 Temperature (°C) ©2008 CADEKA Microcircuits LLC 80 100 1.00 -40 -20 0 20 40 60 80 100 Temperature (°C) www.cadeka.com 6 Data Sheet Typical Performance Characteristics (TA = TMin to TMax, AVCC= +5V, OVDD = +5V, ƒclk = 250MHz, 50% duty cycle, ƒIN = 70MHz, dual channel mode; unless otherwise noted) Input Bandwidth Common-Mode Ref. Voltage vs. VCC -2.50 0 -2.48 VCMOUT (V) dB -1 -2 -3 0 100 -2.44 200 300 400 500 600 -2.40 4.9 5.1 5.3 5.5 5.7 OVDD Current vs. Clk. Freq., Dual Mode OVDD Current vs. Clk. Freq., Single Mode 60 100 50 OVDD = 5V 60 OVDD = 3V 30 OVDD = 3V 40 20 20 10 50 100 150 200 250 0 300 0 Clock Frequency (MHz) 25 50 75 100 125 150 REV 1A 0 OVDD = 5V 40 mA 80 mA 4.7 VCC (V) 120 0 4.5 Input Frequency (MHz) -2.46 -2.42 -4 -5 CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs 1 Clock Frequency (MHz) Total Power vs. Clock Frequency Diff. Input Common-Mode Oper. Range 6 800 5 OVDD = 5V 700 600 Volts (V) Power Dissipation (mW) 1000 OVDD = 3V 4 3 500 2 400 1 300 0 50 100 150 200 Clock Frequency (MHz) ©2008 CADEKA Microcircuits LLC 250 300 0 -50 -40 Common-Mode Operationg Range -20 0 20 40 60 80 100 Temperature (°C) www.cadeka.com 7 Data Sheet Theory of Operation The analog decode functions are the input buffer, input THAs, three-bit folder, folding interpolators, and pipelining THAs. The input buffer enables the part to withstand railtorail input signals without latchup or excessive currents and also performs single-ended to differential conversion. All of the THAs have the same basic architecture. Each has a differential pair buffer followed by switched emitter followers driving the hold capacitors. The input THA also has hold mode feedthrough cancellation devices. Interleaved mode with data alternately on banks A and B on alternate clock cycles n Parallel mode with bank A delayed one cycle to be synchronous with bank B every other clock cycle n If necessary, the input clock is divided by two. The divided clock selects the correct output bank. The user can synchronize with the divided clock to select the desired output bank via the differential RESET input. The output logic family is CMOS with output OVDD supply adjustable from 2.7V to 5.25V. There are also differential clock output pins that can be used to latch the output data in single bank mode or to indicate the current output bank in demux mode. Finally, a power-down mode is available, which causes the outputs to become tri-state, and overall power is reduced to about 24mW. There is a 2V reference to supply common mode for single-ended inputs that is not shut down in powerdown mode. Figure 1. Single Mode Timing Diagram ©2008 CADEKA Microcircuits LLC www.cadeka.com 8 The digital decode consists of comparators, exclusive of All data on bank A with clock rate limited to one-half maximum n REV 1A The three MSBs of the ADC are generated in the first threebit folder block, the output of which drives a differential reference ladder which also sets the full-scale input range. Differential pairs at the ladder taps generate midscale, quarter and three-quarter scale, overrange, and underrange. Every other differential pair collector is cross-coupled to generate the eighth scale zero crossings. The middle ADC block generates two bits from the folded signals of the previous stages after pipeline THAs. Its outputs drive more pipeline THAs to push the decoding of the three LSBs to the next half clock cycle. The three LSBs are generated in interpolators that are latched one full clock cycle after the MSBs. The output data mode is controlled by the state of the demux mode inputs. There are three output modes: CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs The CDK1300 is a three-step subranger. It consists of two THAs in series at the input, followed by three ADC blocks. The first block is a three-bit folder with over/under range detection. The second block consists of two singlebit folding interpolator stages. There are pipelining THAs between each ADC block. cells for gray to binary decoding, and/or cells used for mostly over/under range logic. There is a total of 2.5 clock cycles latency before the output bank selection. In order to reduce sparkle codes and maintain sample rate, no more than three bits at a time are decoded in any half clock cycle. Data Sheet CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs REV 1A Figure 2. Dual Mode Timing Diagram ©2008 CADEKA Microcircuits LLC www.cadeka.com 9 Data Sheet CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs CDK1300 Figure 3. Typical Interface Circuit REV 1A Figure 4. CLK and Reset Equivalent Circuit (without ESD Diodes) Figure 5. Analog Input Equivalent Circuit Typical Interface Circuit Analog Input Very few external components are required to achieve the stated device performance. Figure 3 shows the typical interface requirements when using the CDK1300 in normal circuit operation. The following sections provide descriptions of the major functions and outline performance criteria to consider for achieving the optimal device performance. The input of the CDK1300 can be configured in various ways depending on whether a single-ended or differential input is desired. ©2008 CADEKA Microcircuits LLC The AC-coupled input is most conveniently implemented using a transformer with a center-tapped secondary winding. The center tap is connected to the VCM pin as shown in Figure 3. To obtain low distortion, it is important that the www.cadeka.com 10 Data Sheet selected transformer does not exhibit core saturation at the full-scale voltage. Proper termination of the input is important for input signal purity. A small capacitor across the input attenuates kickback noise from the internal trackand-hold. The CDK1300 has an on-board common-mode voltage reference circuit (VCM). It is 2.5V and is capable of driving 50μA loads typically. The circuit is commonly used to drive the center tap of the RF transformer in fully differential applications. For single-ended applications, this output can be used to provide the level shifting required for the single-to-differential converter conversion circuit. Bypass VCM to AGND by external 0.01μF capacitor, as shown in Figure 3 on the previous page. Clock Input The clock input on the CDK1300 can be driven by either a single-ended or double-ended clock circuit and can handle TTL, PECL, and CMOS signals. When operating at high sample rates it is important to keep the pulse width of the clock signal as close to 50% as possible. For TTL/CMOS single- ended clock inputs, the rise time of the signal also becomes an important consideration. Figure 6. DC-Coupled Single-Ended to Differential Conversion (power supplies and bypassing are not shown) Input Protection All I/O pads are protected with an on-chip protection circuit. This circuit provides ESD robustness and prevents latchup under severe discharge conditions without degrading analog transmission times. Power-Down Mode To save on power, the CDK1300 incorporates a powerdown function. This function is controlled by the signal on pin PD. When pin PD is set high, the CDK1300 enters the power-down mode. All outputs are set to high impedance. In the powerdown mode the CDK1300 dissipates 24mW typically. ©2008 CADEKA Microcircuits LLC Table 1. Output Data Format Analog Input Output Code D7–D0 +FS 1111 1111 +FS - 1 LSB 1111 111Ø +1 FS 1000 000Ø -FS + 1 LSB 0000 000Ø -FS 0000 0000 The CDK1300 is operated from a single power supply in the range of 4.75V to 5.25V. Normal operation is suggested to be 5.0V. All power supply pins should be bypassed as close to the package as possible. The analog and digital grounds should be connected together with a ferrite bead as shown in the typical interface circuit and as close to the ADC as possible. The output circuitry of the CDK1300 has been designed to be able to support three separate output modes. The demuxed (double-wide) mode supports either parallel aligned or interleaved data output. The single-channel mode is not demuxed and can support direct output at speeds up to 125 MSPS. The output format is straight binary (Table 1). REV 1A Power Supplies and Grounding Digital Outputs Ø indicates the flickering bit between logic 0 and 1 The data output mode is set using the DMODE1 and DMODE2 inputs (pins 32 & 31 respectively). Table 2 describes the mode switching options. Table 2. Output Data Modes Output Mode CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs Figure 6 illustrates a solution (based on operational amplifiers) that can be used if a DC-coupled single-ended input is desired. Common-Mode Voltage Reference Circuit DMODE1 DMODE2 Parallel Dual Channel Output 0 0 Interleaved Dual Channel Output 0 1 Single Channel Data Output (Bank A only 125 MSPS max) 1 X www.cadeka.com 11 Data Sheet Evaluation Board transformer (1:1). An application note (TBD) describing the operation of this board, as well as information on the testing of the CDK1300, is also available. Contact the factory for price and availability of the TBD. Mechanical Dimensions TQFP-44 Package TQFP-44 A B INCHES PIN1 Index C D E SYMBOL A B C D E F G H I J K MIN TYP 0.472 0.394 0.394 0.472 0.031 0.012 0.053 0.002 0.018 0.039 0-7° MILLIMETERS MAX MIN 0.018 0.057 0.006 0.030 0.300 1.35 0.05 0.45 TYP MAX 12.00 10.00 10.00 12.00 0.80 0.45 1.45 0.15 0.75 1.00 0-7° F G H I K J CDK1300 8-bit, 250 MSPS ADC with Demuxed Outputs The TBD evaluation board is available to aid designers in demonstrating the full performance of the CDK1300. This board includes a clock driver and reset circuit, adjustable references and common mode, a single-ended to differential input buffer and a single-ended to differential REV 1A 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 ©2008 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