PRODUCT SPECIFICATION 10-Bit 50MSPS Sampling Analog-to-Digital Converter nAD1050-18 FEATURES APPLICATIONS • • • • • • • • • • • • • • • 1.8V power supply SNR typ 59dB for (fin = 10MHz) Low power (33mW @ 1.8V and 50MSPS) Frequency dependent biasing Internal Sample/Hold Differential input Low input capacitance Power Down and Sleep Mode Imaging Test equipment Computer scanners Wireless communication Powerline communication Set top boxes Video products GENERAL DESCRIPTION The nAD1050-18 is a compact, high-speed, low power 10-bit monolithic analog-todigital converter, implemented in a 0.18µm single poly CMOS process with MiM capacitor option. The converter includes a high bandwidth sample and hold. Using internal references, the full scale range is ±0.75V. The full scale range can be set between ±0.5V and ±0.75V using external references. It operates from a single 1.8V supply. Its low distortion and high dynamic range offers the performance needed for demanding imaging, multimedia, telecommunications and instrumentation applications. The bias current level for the ADC is automatically adjusted based on the clock input frequency. Hence, the power dissipation of the device is continuously minimised for the current operation frequency. QUICK REFERENCE DATA Symbol VDD IDD PD PD DNL INL fS N Parameter Conditions Supply voltage Supply current (50 MSPS) Power dissipation (10 MSPS) Power dissipation (50 MSPS) Differential nonlinearity Integral nonlinearity Conversion rate Resolution Min. Typ. Max. Unit 1.6 1.8 18.3 2.0 V mA Except digital output drivers Except digital output drivers fIN=0.9991MHz 8 mW 33 mW fIN=0.9991MHz ±0.5 LSB ±0.75 LSB MHz bit 50 10 Table 1. Quick reference data Main office: Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989 Revision: 3.0 Page 1 of 11 August 31st 2001 PRODUCT SPECIFICATION nAD1050-18 10 Bit 50 MSPS Sampling ADC IP GENERAL DESCRIPTION (Continued) The nAD1050-18 has a pipelined architecture - resulting in low input capacitance. Digital error correction of the 9 most significant bits ensures good linearity for input frequencies approaching Nyquist. The nAD1050-18 is compact. The core occupies less than 0.9mm2 of die area in a standard single poly 0.18µm CMOS process. The fully differential architecture makes it insensitive to substrate noise. Thus it is ideal as a mixed signal ASIC macro cell. BLOCK DIAGRAM REFP REFN EXTREF BIAS0 BIAS1 ANALOG INN CLOCK ANCLOCK CK0 CK0B CK2 CK2B CLOCKBUF INP VCM CKBUS<3:0> IN_CORR<17:0> CKCORR<1:0> CORR_LOG BIT<9:0> Figure 1. Block diagram nAD1050-18 Main office: Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989 Revision: 3.0 Page 2 of 11 August 31st 2001 PRODUCT SPECIFICATION nAD1050-18 10 Bit 50 MSPS Sampling ADC IP ELECTRICAL SPECIFICATIONS (At TA = 25°C, VDD = 1.8V, Sampling Rate = 50MHz, Input frequency = 10MHz, Differential input signal, 50% duty cycle clock unless otherwise noted ) Symbol Parameter (condition) DNL INL VOS CMRR εG SNR SINAD SFDR VFSR VCMI CINA VREFNI VREFPI VREFNO VREFPO VREFP-VREFN VCM FS tAP th td tAP th td DC Accuracy Differential Nonlinearity fIN = 0.9991 MHz Integral Nonlinearity fIN = 0.9991 MHz Midscale offset Common Mode Rejection Ratio Gain Error Dynamic Performance Signal to Noise Ratio (without harmonics) fIN = 10 MHz fIN = 40 MHz Signal to Noise and Distortion Ratio fIN = 10 MHz Spurious Free Dynamic Range fIN = 10 MHz fIN = 40 MHz Analog Input Input Voltage Range (differential) Common mode input voltage Input Capacitance (from each input to ground) Reference Voltages Internal reference voltage on pin 10 Internal reference voltage on pin 11 Internal reference voltage drift Negative Input Voltage Positive Input Voltage Reference input voltage range 1) Common mode output voltage Switching Performance Conversion Rate Pipeline Delay Aperture delay, IP Output hold time, IP Output delay time, IP Aperture delay, with bonding pad Output hold time, with bonding pad Output delay time, with bonding pad Test Level Min. Typ. Max. Units IV ±0.5 LSB IV ±0.75 ±1 -59 ±1 LSB %FS dB %FS 59 58.5 dBFS dBFS IV 59 dBFS IV IV 65 57 dB dB IV IV ±0.75 0.9 1.5 V V pF IV IV 0.525 1.275 IV IV IV IV 0.525 1.275 0.75 0.9 V V ppm/°C V V V V IV IV V V V V V V 50 6 0.9 0.5 2.5 1.0 1.0 4.0 MSPS Clocks ns ns ns ns ns ns IV IV 56 55 100 Digital Inputs VIL VIH IIL IIH CIND Logic “0” voltage Logic “1” voltage Logic “0” current (VI=VSS) Logic “1” current (VI=VDD) Input Capacitance IV IV IV IV IV 0.4 AVDD -0.4 ±10 ±10 5 V V µA µA pF (table continued on next page) Main office: Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989 Revision: 3.0 Page 3 of 11 August 31st 2001 PRODUCT SPECIFICATION nAD1050-18 10 Bit 50 MSPS Sampling ADC IP VOL VOH VDD IDD VSS PD PD PD PD AVDDDVDD1 OVDD T Digital Outputs Logic “0” voltage (I = 2 mA) Logic “1” voltage (I = 2 mA) Power Supply Supply voltage Supply current (except digital output) Supply voltage Power dissipation (except digital output) (10 MSPS) Power dissipation (except digital output) (50 MSPS) Power dissipation (except digital output) 2) Power Down Mode Power dissipation (except digital output) Sleep Mode Analog power – digital power pins IV IV V IV 0.2 85% OVDD 90% OVDD 1.6 1.8 0.4 V V 2.0 V mA IV GND 8 mW IV 33 mW IV 45 µW IV 655 µW Output driver supply voltage Ambient operating temperature -0.2 1.6 -40 1.8 +0.2 V 2.0 +85 V °C Table 2. Electrical specifications 1) See Figure 5. 2) Power Down Mode is only available for IP version of nAD1050-18. Test Levels Test Level I: 100% production tested at +25°C Test Level II: 100% production tested at +25°C and sample tested at specified temperatures Test Level III: Sample tested only Test Level IV: Parameter is guaranteed by design and characterization testing Test Level V: Parameter is typical value only Test Level VI: 100% production tested at +25°C. Guaranteed by design and characterization testing for industrial temperature range ABSOLUTE MAXIMUM RATINGS Supply voltages AVDD ............................- 0.2V to +2.2V DVDD1 ..................- 0.2V to VDD + 0.2V OVDD ...................- 0.2V to VDD + 0.2V Temperatures Operating Temperature ….-40 to +85°C Storage Temperature.. ... - 65 to +125°C Input voltages Analog In.......... - 0.2V to AVDD + 0.2V Digital In..............- 0.2V to VDD + 0.2V REFP ................. - 0.2V to AVDD + 0.2V REFN................. - 0.2V to AVDD + 0.2V CLOCK ...............- 0.2V to VDD + 0.2V Note: Stress above one or more of the limiting values may cause permanent damage to the device. Main office: Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989 Revision: 3.0 Page 4 of 11 August 31st 2001 PRODUCT SPECIFICATION nAD1050-18 10 Bit 50 MSPS Sampling ADC IP PIN FUNCTIONS Pin Name Description INP INN REFP REFN Differential input signal pins. Common mode voltage: 0.9V Reference input pins. Bypass with 100nF capacitors close to the pins. See Application Information below. BIAS0, BIAS1 Digital inputs for max. sampling rate programming. BIAS1=0, BIAS0=0: Sleep mode (power save) BIAS1=0, BIAS0=1: - 12.5% bias BIAS1=1, BIAS0=0: +12.5% bias BIAS1=1, BIAS0=1: Typ. Bias CLOCK VCM BIT9 - BIT0 OR OUTEN EXTREF PD VDD VSS OVDD The bias setting is automatically performed based on the clock input frequency. This function should be used ONLY if another bias setting than typical must be used. Clock input Common mode voltage output Digital outputs ( MSB to LSB) OverRange. High if all outputs are zeros or ones. Available on IP. Enable digital outputs (Keep low for active outputs) Disable internal references (Keep low for internal references) Power Down (Keep low for normal operation) Available on IP or with bonding option. Power pins for on chip power Ground pins Power pins for output drivers Table 3. Pin functions PIN ASSIGNMENT BIT9 1 28 OUTEN BIT8 2 27 CLOCK BIT7 3 26 BIAS1 BIT6 4 25 BIAS0 BIT5 5 24 INP OVDD 6 23 INN OVDD 7 22 VDD VSS 8 21 VSS VSS 9 20 VCM BIT4 10 nAD1050-18 BIT3 11 28 PIN SSOP 19 EXTREF 18 REFP BIT2 12 17 REFN BIT1 13 16 VDD BIT0 14 15 VSS Figure 2. Pin assignment for the 28 pin package used for samples Main office: Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989 Revision: 3.0 Page 5 of 11 August 31st 2001 PRODUCT SPECIFICATION nAD1050-18 10 Bit 50 MSPS Sampling ADC IP BIAS0 BIAS1 EXTREF INP INN VCM IP BLOCK LAYOUT AVSS AVSS AVDD AVDD REFP REFN VDD CLOCK Y X AVDD AVSS AVSS OR BIT9 : BIT0 AVDD Figure 3. Size and pin placement for nAD1050-18. The height and width of the layout is X =1208µm and Y=711µm respectively in the 0.18µm CMOS process. TIMING DIAGRAM CLOCK S A M N-1 P L E DATA S A M N P L E S A M N+1 P L E tAP S A M N+2 P L E t t h Data N-1 d Data N Data N+1 Figure 4. Timing diagram Main office: Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989 Revision: 3.0 Page 6 of 11 August 31st 2001 PRODUCT SPECIFICATION nAD1050-18 10 Bit 50 MSPS Sampling ADC IP INPUT SIGNAL RANGE VREFP VINP VCM VINN VRR VREFN +VRR VFSR VINP-VINN -VRR Figure 5. Definition of full scale range DEFINITIONS Data sheet status Objective product specification Preliminary product specification Product specification This datasheet contains target specifications for product development. This datasheet contains preliminary data; supplementary data may be published from Nordic VLSI ASA later. This datasheet contains final product specifications. Limiting values Stress above one or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or at any other conditions above those given in the Specifications sections of the specification is not implied. Exposure to limiting values for extended periods may affect device reliability. Application information Where application information is given, it is advisory and does not form part of the specification. Table 4. Definitions LIFE SUPPORT APPLICATIONS These products are not designed for use in life support appliances, devices, or systems where malfunction of these products can reasonably be expected to result in personal injury. Nordic VLSI ASA customers using or selling these products for use in such applications do so at their own risk and agree fully indemnify Nordic VLSI ASA for any damages resulting from such improper use or sale. Main office: Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989 Revision: 3.0 Page 7 of 11 August 31st 2001 PRODUCT SPECIFICATION nAD1050-18 10 Bit 50 MSPS Sampling ADC IP APPLICATION INFORMATION References The nAD1050-18 has a differential analog input. The input range is determined by the voltages VREFP and VREFN applied to reference pins REFP and REFN respectively, and is equal to ±(VREFP-VREFN). Externally generated reference voltages connected to REFP and REFN should be symmetrical around 0.9V. The input range can be defined between ±0.5V and ±0.75V. The references should be bypassed as close to the converter pins as possible using 100nF capacitors in parallel with smaller capacitors (e.g. 1nF) (to ground). Analog input The input of the nAD1050-18 can be configured in various ways - dependent upon whether a single ended or differential, AC- or DC-coupled input is wanted. AC-coupled input is most conveniently implemented using a transformer with a center tapped secondary winding. The center tap is connected to the CM-node, as shown in figure 6. In order to obtain low distortion, it is important that the selected transformer does not exhibit core saturation at full-scale. Excellent results are obtained with the Mini Circuits T1-6T or T1-1T. Proper termination of the input is important for input signal purity. A small capacitor across the inputs attenuates kickback-noise from the sample and hold. Series resistors as shown in Figure 6 may be advantageous to improve linearity. The VCM-node should be bypassed to ground as closed to the converter pin as possible using 100nF capacitors in parallel with a small one. Vin Mini Circuits T1-6T 50Ω ADC INP 51Ω 22pF VCM INN 50Ω Figure 6. Example of AC coupled input using transformer configuration If a DC-coupled single ended input is wanted, a solution based on operational amplifiers - as shown in Figure 7, is usually preferred. The AD826 is suggested for low distortion and video bandwidth. Lower cost operational amplifiers may be used if the demands are less strict. A good alternative for high performance applications is to use AD8138 single ended to differential amplifier. Main office: Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989 Revision: 3.0 Page 8 of 11 August 31st 2001 PRODUCT SPECIFICATION nAD1050-18 10 Bit 50 MSPS Sampling ADC IP 51Ω 470Ω AD826 Input offset Video in 470Ω ADC 51Ω 100Ω AD826 INP 15pF 100Ω INN 51Ω 51Ω 470Ω AD826 470Ω 470Ω Figure 7. DC-coupled single ended to differential conversion (power supplies and bypassing not shown) Clock In order to preserve accuracy at high input frequency, it is important that the clock has low jitter and steep edges. Rise/fall times should be kept shorter than 2ns whenever possible. Overshoot should be avoided. Low jitter is especially important when converting high frequency input signals. Jitter causes the noise floor to rise proportionally to input signal frequency. Jitter may be caused by crosstalk on the PCB. It is therefore recommended that the clock trace on the PCB is made as short as possible. Digital outputs The digital output data appears in offset binary code at CMOS logic levels. Full-scale negative input results in output code 000...0. Full-scale positive input results in output code 111...1. Output data are available 6 clock cycles after the data are sampled. The analog input is sampled one aperture delay (tAP) after the high to low clock transition. Output data should be sampled as shown in the timing diagram. PCB layout and decoupling A well designed PCB is necessary to get good spectral purity from any high performance ADC. A multilayer PCB with a solid ground plane is recommended for optimum performance. If the system has a split analog and digital ground plane, it is recommended that all ground pins on the ADC are connected to the analog ground plane. It is our experience that this gives the best performance. The power supply pins should be bypassed using 100nF surface mounted capacitors as close to the package pins as possible. Analog and digital supply pins should be separately filtered. Main office: Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989 Revision: 3.0 Page 9 of 11 August 31st 2001 PRODUCT SPECIFICATION nAD1050-18 10 Bit 50 MSPS Sampling ADC IP Dynamic testing Careful testing using high quality instrumentation is necessary to achieve accurate test results on high speed A/D-converters. It is important that the clock source and signal source has low jitter. A spectrally pure, low noise RF signal generator - such as the HP8662A or HP8644B is recommended for the test signal. Low pass filtering or band pass filtering of the input signal is usually necessary to obtain the required spectral purity (SFDR > 75dB). The clock signal can be obtained from either a crystal oscillator or a low-jitter pulse generator. Alternatively, a low-jitter RF-generator can be used as a clock source. At Nordic VLSI, the Marconi Instruments 2041A is used. The sinewave clock must then be applied to an ultra high-speed comparator (e.g. AD9696) and a TTL to CMOS level shifter (e.g. 74LV04) before application to the converter. The most consistent results are obtained if the clock signal is phase locked to the input signal. Phase locking allows testing without windowing of output data. A logic analyzer with deep memory - such as the HP16500-series, is recommended for test data acquisition. Power Down Mode and Sleep Mode The nAD1050-18 has both Power Down Mode and Sleep Mode. The Power Down Mode can be used when the ADC should be put to ‘zero current consumption’ state and when a somewhat longer startup time is allowed. The Sleep Mode can be used to put the ADC in an ‘idle’ state and when the application require a quick startup. The two different power consumption saving schemes can be activated through the PD, BIAS0 and BIAS1 pins/connections in the following manner: Power Down Mode: PD=1, BIAS0=0, BIAS1=0 Sleep Mode: PD=0, BIAS0=0, BIAS1=0 The actual startup time from these modes are dependent on the external decopling configuration. Main office: Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989 Revision: 3.0 Page 10 of 11 August 31st 2001 PRODUCT SPECIFICATION nAD1050-18 10 Bit 50 MSPS Sampling ADC IP DESIGN CENTER Nordic VLSI ASA Vestre Rosten 81 N-7075 TILLER NORWAY Telephone: +47 72898900 Telefax: +47 72898989 E-mail: For further information regarding our state of the art data converters, please email us at [email protected]. World Wide Web/Internet: Visit our site at http://www.nvlsi.no. ORDERING INFORMATION Type number nAD1050-18-IC nAD1050-18-EVB Description nAD1050-18 sample in SSOP28 package (limited availability) nAD1050-18 evaluation board including characterisation report and user guide Table 5. Ordering information Price USD 50 USD 300 Product Specification. Revision Date: August 31st, 2001 All rights reserved ®. Reproduction in whole or in part is prohibited without the prior written permission of the copyright holder. Company and product names referred to in this datasheet belong to their respective copyright/trademark holders. Main office: Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989 Revision: 3.0 Page 11 of 11 August 31st 2001