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ANALOG DEVICES AD45048 handbook

1. G 2 5 z 3 G 1 S G 1 z z o q lt 5 5 10 10 15 15 o 20 20 si 25 3 25 3 10k 100k 1M 10M 100M 1G 10k 100k 1M 10M 100M 1G FREQUENCY Hz FREQUENCY Hz Figure 3 Noninverting Small Signal Bandwidth Figure 6 Noninverting Large Signal Bandwidth Vs 6 V Vo 0 1 Vp p Ri 250 Vs 6 V Vo 1 Vp p Ri 25Q 25 25 x G 10 5kQ 10 5kQ G 5 Re 7 Guus Rg 15 m i 250 250 10 10 G 2 G 2 5 5 3 G 1 8 G 1 7 2 9 q lt 5 5 10 10 15 2 15 m 20 20 25 3 25 3 10k 100k 1M 10M 100M 1G 10k 100k 1M 10M 100M 1G FREQUENCY Hz FREQUENCY Hz Figure 4 Inverting Small Signal Bandwidth Figure 7 Inverting Large Signal Bandwidth Vs 6 V Vo 0 1 Vp p R 25 Q Vs 6 V Vo 1 Vp p Ri 25Q 40 50 Vin i a 60 1000 70 Vin s 80 3 2 0 5 10 15 20 dBm 1000 Figure 5 MTPRvs Line Povver See Schematic in Figure 8 Figure 8 Differential Test Circuit for MTPR Rev A Page 5 of 8 AD45048 N N ey ie gt lt 2 W W o o o o z z 6 5 s a H m o gt gt o FA 10 100 1k 10k 100k 1M 10M 100M 10 100 1k 10k 100k 1M 10M FREQUENCY Hz FREQUENCY Hz Figure 9 Volta
2. Voltage Noise f 100 kHz 4 5 nV VHz Input Current Noise f 100 kHz 1 5 pA VHz DC PERFORMANCE Input Offset Voltage 1 2 5 mV Tmin Tmax 2 5 mv nput Offset Voltage Match 1 2 0 mv nput Bias Current 200 900 nA Tmn Tmax 1 3 HA nput Offset Current 50 300 nA Open Loop Gain 85 94 dB INPUT CHARACTERISTICS Input Resistance f 100 kHz 87 kO nput Capacitance 1 4 pF OUTPUT CHARACTERISTICS Output Resistance 1 4 MHz G 1 0 2 Q Output Voltage Swing Maximum swing differential Vomax R oap 50 Q differential 11 25 11 5 V diff Minimum swing differential Vom Rtoap 50 Q differential 11 5 11 25 V diff Differential Output Voltage Swing AVout Vomax Vomin 22 5 23 V p p Single Ended Swing Roan 250 5 68 5 76 Vp Single Ended Swing Roan 250 5 67 5 58 Vp Single Ended Swing Roan 100 Q 5 92 5 95 Vp Single Ended Svving Roan 100 Q 5 91 5 86 Vp Operating Range Dual Supply 15 126 V Supply Current 7 9 12 mA Power Supply Rejection Ratio 0 5V 85 75 dB Common Mode Rejection Ratio 1 V 86 79 dB Rev A Page 3 of 8 AD45048 ABSOLUTE MAXIMUM RATINGS a Rating Stresses above those listed under Absolute Maximum Ratings Supply Voltage 264V may cause permanent damage to the device This is a stress Power Dissipation Timax Ta O a rating only functional operation of the device at these or any Storage Temperature 65 C to 125 C other conditions above those indicated in the
3. operational Operating Temperature Range 40 C to 85 C section of this specification is not implied Exposure to absolute Lead Temperature Range 300 C maximum rating conditions for extended periods may affect Soldering 10 sec device reliability Junction Temperature 150 C 1 a 112 7 C W for SOIC package in still air based on 252P JEDEC PCB ESD CAUTION ESD electrostatic discharge sensitive device Electrostatic charges as high as 4000V readily accumulate on the human body and test equipment and can discharge without detection Although this product features BAYAT E proprietary ESD protection circuitry permanent damage may occur on devices subjected to high energy At electrostatic discharges Therefore proper ESD precautions are recommended to avoid performance degradation or loss of functionality ESD SENSITIVE DEVICE Rev A Page 4 of 8 AD45048 TYPICAL PERFORMANCE CHARACTERISTICS 25 G 10 i G 10 pan 20 Ro 7 Rg 15 G 5 15 G 5 250 250 10 10 G 2
4. range make the AD45048 ideal for driving upstream signals in ADSL CPE applications Fabricated with ADTs high speed XFCB HV eXtra Fast Complementary Bipolar High Voltage process the high bandwidth and fast slew rate of the AD45048 keep distortion to a minimum while dissipating minimum power The AD45048 is available in a standard 8 lead SOIC package that can operate from 40 C to 85 C Rev A Information furnished by Analog Devices is believed to be accurate and reliable However no responsibility is assumed by Analog Devices for its use nor for any infringements of patents or other rights of third parties that may result fromits use Specifications subject to change without notice No One Technology Way P O Box 9106 Norwood MA 02062 9106 U S A license is granted by implication or otherwise under any patent or patent rights of Analog Devices Tel 781 329 4700 www analog com Trademarks and registered trademarks are the property of their respective owners Fax 781 461 3113 2005 Analog Devices Inc All rights reserved AD45048 TABLE OF CONTENTS Features ao SNe SN ono 1 General Descriptio ia a ER ERE Applicaton Sinsin E R E 1 Power Supply and Decoupling ssesssssssssssssssssssssssssrtrsssssssssrssese General DESGrIptioniivciscesescsatesssssetnesscsenscovssspesesniorecesscetssspsneteaorsestent 1 Layout ConsiderationS ssssssssssssssssisssssssssssrsettessssssssssreerteesssssssss Pin Configuration sssss ssssesssssss
5. 48ARZ 40 C to 85 C 8 Lead Standard Small Outline Package SOIC_N R 8 AD45048ARZ REEL 40 C to 85 C 8 Lead Standard Small Outline Package SOIC_N R 8 AD45048ARZ REEL71 40 C to 85 C 8 Lead Standard Small Outline Package SOIC_N R 8 Z Pb free part 2005 Analog Devices Inc All rights reserved Trademarks and ANALOG registered trademarks are the property of their respective owners D04817 0 9 05 A DEVICES www analo g com Rev A Page 8 of 8
6. 7 5 V peak onto the 100 0 telephone line while maintaining about 65 dBc to 70 dBc of MTPR Since the maximum low distortion output swing available from the AD45048 line driver is approximately 11 5 V on a 12 V supply depending on the load and taking into account the power lost in the transformer and termination resistors a step up transformer with a minimum turns ratio of 1 5 or greater is needed In the simplified differential driver circuit shown in Figure 8 the AD45048 is driving a 25 Q impedance reflected by 1 2 step up transformer R3 and R6 are 12 5 O each and are back termination or load matching resistors whose values can be calculated by 100 0 N 2 where 100 Q is the approximate phone line impedance and N is the transformer turns ratio In Figure 8 the total differential load including the termination resistors is 50 Q and under these conditions the AD45048 is capable of driving low distortion signals to within 0 5 V of the power rails RECEIVE CHANNEL CONSIDERATIONS A step up transformer of N turns used at the output of the differential line driver increases the differential output voltage to the line see Figure 8 However the inverse effect is seen in the receive channel as the amplitude of signal on the driver side of the transformer is divided by N turns The decision to use a particular transformer turns ratio may be impacted by the ability of the receive circuitry to resolve low level signals in the noisy t
7. ANALOG DEVICES _ Rail to Rail Upstream ADSL Line Driver AD45048 FEATURES PIN CONFIGURATION Dual op amp Voltage feedback Wide supply range from 3 3 V to 24V Rail to rail output Output swing to within 0 5 V of supply rails 230 mA 23 V p p differential Rioan of 50 O from 12 V supply High output current Linear output current of 230 mA peak into 250 68 dBc MTPR o 15 dBm 100 Q telephone line Low noise 4 5 nV NHz voltage noise density 100 kHz 1 5 pA VHz current noise density 100 kHz High speed 65 MHz bandwidth Av 1 3 dB 55 V us slew rate Rioap 25 0 04817 Sp0 001 dBm APPLICATIONS rl Consumer xDSL modems Twisted pair line drivers ADSL CPE applications Drop in replacement for TS6131D and EL1519CS Audio applications of l 5 04817 Sp0 002 CENTER 86 31174378kHz TkHz SPAN 10kHz Figure 2 AD45048AR Upstream ADSL MTPR 13 dBm CF 5 3 GENERAL DESCRIPTION The AD45048 ADSL CPE line driver is a dual operational amplifier capable of driving high output current 230 mA it features a rail to rail output stage that swings to within 0 5 V of the supply rails The AD45048 rail to rail output stage surpasses the output voltage capability of typical emitter follower output stages and can deliver up to 23 V p p differentially from a single 12 V supply in ADSL CPE line driving applications The low distortion high output current and wide output dynamic
8. ge Noise vs Frequency Vs 6 V Figure 12 Input Current Noise vs Frequency Vs 6 V 0 20 SECOND 7 8 si 5 40 u 10 m o 3 z z a Li E 60 a 1 o E Le 2 a 80 R 0 1 a o 100 e o a 1000 i f 04817 Sp0 028 04817 Sp0 030 120 0 001 1 2 3 4 5 6 9 10 11 10k 100k 1M 10M 100M OUTPUT VOLTAGE p p FREQUENCY Hz Figure 10 Single Ended Harmonic Distortion Vs 6 V dc G 6 Figure 13 Output Impedance vs Frequency Rr 499 O Re 100 O Ri 25 O Fundamental Frequency 40 kHz 50mV DIV 04817 Sp0 029 04817 Sp0 031 M 100ns Figure 11 Discrete Multitone Modulation Overdrive Recovery Figure 14 Small Signal Pulse Response Rioap 1 kO Rre 500 Q See Schematic in Figure 8 M 5 00us Rev A Page 6 of 8 AD45048 GENERAL DESCRIPTION The AD45048 is a voltage feedback rail to rail output amplifier with high output current capability Fabricated on Analog Devices proprietary high speed eXtra fast complementary bipolar high voltage process XFCB HV the high bandwidth and fast slew rate of the AD45048 keep distortion to a minimum while dissipating minimum power The XFCB HV silicon on insulator SOI process prevents latch up problems and enables the construction of high frequency low distortion amplifiers such as the AD45048 POWER SUPPLY AND DECOUPLING T
9. he AD45048 can be powered with a good quality well regulated low noise supply anywhere in the range from 3 V to 12 6 V In order to optimize the AD45048 in standard ADSL CPE line driver applications see Figure 8 power the amplifier with a well regulated 12 V supply Careful attention should be paid to decoupling the power supply High quality capacitors with low equivalent series resistance ESR such as multilayer ceramic capacitors MLCCs should be used to minimize the supply voltage ripple and power dissipation A 0 1 uF MLCC decoupling capacitor s should be located no more than 1 8 inch away from the power supply pin s A large usually tantalum 10 uF to 47 uF capacitor is recommended to provide good decoupling for lower frequency signals and to supply current for fast large signal changes at the AD45048 outputs LAYOUT CONSIDERATIONS As is the case with all high speed applications careful attention to printed circuit board layout details prevents associated board parasitics from becoming problematic Proper RF layout and printed circuit board design techniques are strongly recommended The PCB should have a low impedance return path or ground to the supply Removing the ground plane from all layers in the immediate area of the amplifier reduces stray capacitances The signal routing should be short and direct in order to minimize the parasitic inductance and capacitance associated with these traces Termination resistors and
10. loads should be located as close as possible to their respective inputs and outputs Input traces should be kept as far apart as possible from the output traces to minimize coupling crosstalk though the board Wherever there are complementary signals a symmetrical layout should be provided to the extent possible in order to maximize balanced performance When running differential signals over a long distance the traces on the PCB should be close together or any differential wiring should be twisted together to minimize the area of the loop that is formed This reduces the radiated energy and makes the circuit less susceptible to RF interference Adherence to stripline design techniques for long signal traces greater than about 1 inch is recommended CPE ADSL APPLICATION The low cost high output current dual AD45048 xDSL line driver amplifiers have been specifically designed to drive high fidelity xDSL signals to within 0 5 V of the power rails on a single 12 V supply The AD45048 can be used in transformer coupled bridge hybrid circuits designed to drive modulated signals including discrete multitone DMT upstream to the central office TRANSFORMER SELECTION Customer premise ADSL applications require the transmission ofa 13 dBm DMT signal 20 mW into 100 Q DMT signals can have a crest factor V peak V rms ratio as high as 5 3 requiring the line driver to provide a peak power of 560 mW The line driver is required to drive a
11. ssessesssssssssessertesessssssserserersesssssnssseee 1 CPE ADSL Application sssssssssssssssssssssssssssssssssssrtesesssssssersereeesss Revision History oraiiio i iE A K E 2 Transformer Selection siisii a a Specifications aaa e R 3 Receive Channel Considerations c ccssscesesseessessesssssessesnes Absolute Maximum Ratings s l 4 Outline Dimensions eani E sl n ESD Gatti fen nuenpneunnen naunan anain 4 Ordering Guide Arisiki sbacsssssueaserasnsstavesascsssesecascueseaciivsteses Typical Performance Characteristics 5 REVISION HISTORY 9 05 Rev 0 to Rev A Updated Outline Dimensions Changes to Ordering Guide n 7 04 Revision 0 Initial Version Rev A Page 2 of 8 SPECIFICATIONS AD45048 Vs 6 V or 12 V Ta 25 C G 10 Ri 100 Q unless otherwise noted Table 1 Parameter Test Conditions Comments Min Typ Max Unit DYNAMIC PERFORMANCE 3 dB Bandwidth G 1 Vout 0 1 V p p Rre 0 O Rioap 250 65 MHz 0 1 dB Flatness Vout 0 1 V p p single ended G 1 Rioap 250 3 35 MHz Large Signal Bandwidth Vour 1 V p p single ended G 10 Rioap 250 45 MHz Large Signal Slew Rate Vout 5 V p p G 1 Roan 250 55 V us NOISE DISTORTION PERFORMANCE Distortion VVorst Harmonic fc 40 kHz Vout 6 V p p single ended Rioap 25 Q 80 dBc Multitone Power Ratio 26 kHz to 134 kHz Zune 100 O XFMR 1 2 turns Pune 13 dBm 68 dBc Input
12. wisted pair telephone plant Higher turns ratio transformers reduce the effective receive channel SNR signal to noise ratio due to the reduction in the received signal strength An amplifier with low RTI noise such as the AD8022 2 5 nV VHz is recommended for the receive channel For a complete selection of amplifiers and other related components see www analog com Rev A Page 7 of 8 AD45048 OUTLINE DIMENSIONS 5 00 0 1968 as 0 1 n H HHH ry 4 00 0 1574 6 20 0 2440 3 80 0 1497 5 80 0 2284 y sl ie 1 27 0 0500 0 50 0 0196 z BSC 1 75 0 0688 ii B 0 25 0 0099 4 0 25 0 0098 1 35 0 0532 0 10 0 0040 0 51 0 0201 4 z PEREN COPLANARITY Stara 0 31 0 0122 0 25 0 0098 127 m PLANE 0 17 0 0067 40 0 COMPLIANT TO JEDEC STANDARDS MS 012 AA CONTROLLING DIMENSIONS ARE IN MILLIMETERS INCH DIMENSIONS IN PARENTHESES ARE ROUNDED OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN Figure 15 8 Lead Standard Small Outline Package SOIC_N Narrow Body R 8 Dimensions shown in millimeters and inches ORDERING GUIDE Model Temperature Range Package Description Package Option AD45048AR 40 C to 85 C 8 Lead Standard Small Outline Package SOIC_N R 8 AD45048AR REEL 40 C to 85 C 8 Lead Standard Small Outline Package SOIC_N R 8 AD45048AR REEL7 40 C to 85 C 8 Lead Standard Small Outline Package SOIC_N R 8 AD450

ANALOG DEVICES AD45048 handbook

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