TS613 DUAL WIDE BAND OPERATIONAL AMPLIFIER WITH HIGH OUTPUT CURRENT ■ LOW NOISE : 3nV/√Hz, 1.2pA/√Hz ■ HIGH OUTPUT CURRENT : 200mA ■ VERY LOW HARMONIC AND INTERMODULATION DISTORTION ■ HIGH SLEW RATE : 40V/µs ■ SPECIFIED FOR 25Ω LOAD DESCRIPTION The TS613 is a dual operational amplifier featuring a high output current (200mA min.), large gain-bandwidth product (130MHz) and capable of driving a 25Ω load with a 160mA output current at ±6V power supply. D SO-8 (Plastic Micropackage) PIN CONNECTIONS (top view) This device is particularly intended for applications where multiple carriers must be amplified simultaneously with very low intermodulation products. The TS613 is housed in a SO8 package. APPLICATION ■ UPSTREAM line driver for Assymetric Digital Subscriber Line (ADSL) (NT). ORDER CODE Package Part Number Temperature Range D TS613ID -40, +85°C • D = Small Outline Package (SO) - also available in Tape & Reel (DT) May 2000 1/9 TS613 ABSOLUTE MAXIMUM RATINGS Symbol VCC Vid Parameter Supply voltage 1) Differential Input Voltage 2) Value Unit ±7 V ±2 V ±6 V Toper Operating Free Air Temperature Range TS612ID -40 to + 85 °C Tstd Storage Temperature -65 to +150 °C 150 °C Vin Tj Input Voltage Range 3) Maximum Junction Temperature Rthjc Thermal Resistance Junction to Case 28 °C/W R tha Thermal Resistance Junction to Ambient Area 175 °C/W P max. Maximum Power Dissipation (@25°C) 715 mW Output Short Circuit Duration 4) 1. All voltages values, except differential voltage are with respect to network terminal. 2. Differential voltages are non-inverting input terminal with respect to the inverting input terminal. 3. The magnitude of input and output voltages must never exceed VCC +0.3V. 4. An output current limitation protects the circuit from transient currents. Short-circuits can cause excessive heating. Destructive dissipation can result from short circuit on amplifiers. OPERATING CONDITIONS Symbol VCC Vicm Parameter Supply Voltage Common Mode Input Voltage Value Unit ±2.5 to ±6 V (VCC) +2 to (V CC+) -1 V 2/9 TS613 ELECTRICAL CHARACTERISTICS. Symbol VCC = ±6V, Tamb = 25°C (unless otherwise specified). Parameter Test Conditi on Min. Typ. Max Unit -6 -1 6 10 mV 6 mV 0.2 3 µA 5 5 15 30 DC PERFORMANCE Vio ∆V io Input Offset Voltage Differential Input Offset Voltage Tamb Tmin. < Tamb < Tmax. Tamb = 25°C Tamb Iio Input Offset Current Iib Input Bias Current Tamb Tmin. < Tamb < Tmax. CMR Common Mode Rejection Ratio Vic = 2V to 2V, Tamb Tmin. < Tamb < Tmax. 90 SVR Supply Voltage Rejection Ratio Vic = ±6V to ±4V, T amb 70 50 ICC Total Supply Current per Operator Tmin. < Tamb < Tmax. Tmin. < Tamb < Tmax. 108 dB 70 No load, Vout = 0 µA 88 dB 11 15 mA 4.5 -4.5 -4 V V DYNAMIC PERFORMANCE VOH VOL AVD GBP SR Iout Isink High Level Output Voltage Low Level Output Voltage Iout = 160mA, RL to GND Iout = 160mA, RL to GND Large Signal Voltage Gain Vout = 7V peak RL = 25Ω, Tamb Tmin. < Tamb < Tmax. 4 6500 Gain Bandwidth Product AVCL = +11, f = 20MHz RL = 100Ω 80 Slew Rate AVCL = +7, RL = 50Ω 23 Output Short Circuit Current Output Sink Current Vic = ±6V, Tamb Tmin. < Tamb < Tmax. 11000 V/V 130 MHz 40 V/µs ±320 mA 5000 +200 +180 mA Isource Output Source Current Vic = ±6V, Tamb Tmin. < Tamb < Tmax. ΦM14 Phase Margin at A VCL = 14dB Phase Margin at A VCL = 6dB RL = 25Ω//15pF RL = 25Ω//15pF 60 ° 40 ° f = 100kHz f = 100kHz Vout = 4Vpp, f = 100kHz AVCL = -10 RL = 25Ω//15pF 3 1.2 nV/√Hz pA/√Hz -69 dB -70 dBc -74 dBc -79 dBc -77 dBc -77 dBc ΦM6 -200 -180 mA NOISE AND DISTORTION en in Equivalent Input Noise Voltage Equivalent Input Noise Current THD Total Harmonic Distorsion HD2-10 2nd Harmonic Distorsion HD2 +2 2nd Harmonic Distorsion HD3 +2 3rd Harmonic Distorsion IM2-10 2nd Order Intermodulation Product IM3-10 3rd Order Intermodulation Product 3/9 Vout = 4Vpp, f = 100kHz AVCL = -10 Load =25Ω//15pF Vout = 4Vpp, f = 100kHz AVCL = +2 Load =25Ω//15pF Vout = 4Vpp, f = 100kHz AVCL = +2 Load =25Ω//15pF F1 = 80kHz, F2 = 70kHz Vout = 8Vpp, AVCL = -10 Load = 25Ω//15pF F1 = 80kHz, F2 = 70kHz Vout = 8Vpp, AVCL = -10 Load = 25Ω//15pF TS613 INTERMODULATION DISTORTION The curves shown below are the measurements results of a single operator wired as an adder with a gain of 15dB. The operational amplifier is supplied by a symmetric ±6V and is loaded with 25Ω. Two synthesizers (Rhode & Schwartz SME) generate two frequencies (tones) (70 & 80kHz ; 180 & 280kHz). An HP3585 spectrum analyzer measures the spurious level at different frequencies. The curves are traced for different output levels (the value in the X ax is the value of each tone). The output levels of the two tones are the same. The generators and spectrum analyzer are phase locked to enhance measurement precision. 3rd ORDER INTERMODULATION Gain=15dB, Vcc=± 6V, RL=25Ω, 2 tones 180kHz/ 280kHz 0 0 -10 -10 -20 -20 -30 -30 -40 IM3 (dBc) IM3 (dBc) 3rd ORDER INTERMODULATION Gain=15dB, Vcc=± 6V, RL=25Ω, 2 tones 70kHz/ 80kHz 90kHz -50 230kHz -60 -40 -50 80kHz -60 380kHz -70 -70 -80 -80 60kHz -90 220kHz -100 1 1,5 2 640kHz -90 2,5 740kHz -100 3 3,5 4 4,5 1 1,5 2 2,5 3 3,5 4 4,5 Vout peak (V) Vout peak (V) 2nd ORDER INTERMODULATION Gain=15dB, Vcc=± 6V, RL=25Ω, 2 tones 180kHz/ 280kHz, Spurious measurement @100kHz IM2 (dBc) -55 -60 -65 -70 1,5 2 2,5 3 3,5 4 4,5 Vout peak (V) 4/9 TS613 Closed Loop Gain and Phase vs. Frequency Gain=+2, Vcc=± 6V, RL=25Ω 10 Closed Loop Gain and Phase vs. Frequency Gain=+6, Vcc=± 6V, RL=25Ω 200 200 20 Gain Gain -10 Phase 0 -20 -100 -30 -200 100 10 5 0 Phase 0 -5 Phase (degrees) 100 Gain (dB) 0 Phase (degrees) Gain (dB) 15 -100 -10 -15 10kHz 100kHz 1MHz 10MHz -20 100MHz -200 10kHz 100kHz 1MHz Frequency 10MHz 100MHz Frequency Closed Loop Gain and Phase vs. Frequency Gain=+11, Vcc=± 6V, RL=25Ω 30 Equivalent Input Voltage Noise Gain=+100, Vcc=± 6V, no load 200 20 100 15 Gain Phase 0 0 -10 en (nV/VHz) Gain (dB) 10 Phase (degrees) 20 + _ 10k 100 10 -100 5 -200 0 -20 -30 10kHz 100kHz 1MHz 10MHz Frequency 1kHz 10kHz 100kHz 1MHz Frequency Maximum Output Swing Vcc=± 6V, RL=25Ω Channel Separation (Xtalk) vs. Frequency XTalk=20Log(V2/V1), Vcc=± 6V, RL=25Ω 5 -20 VIN 4 output 2 Xtalk (dB) -40 input 1 + 4 9.9Ω _ -30 3 swing (V) 100Hz 100MHz 0 100Ω + 4 9.9Ω _ -50 -1 -60 -2 V1 1kΩ 100Ω 25Ω V2 1kΩ 25Ω -3 -70 -4 -5 0 2 4 6 Time (µs) 5/9 8 10 -80 10kHz 100kHz 1MHz Frequency 10MHz TYPICAL APPLICATION : TS613 AS DRIVER FOR ADSL LINE INTERFACES A SINGLE SUPPLY IMPLEMENTATION WITH PASSIVE OR ACTIVE IMPEDANCE MATCHING by C. PRUGNE ADSL CONCEPT Asymmetric Digital Subscriber Line (ADSL), is a new modem technology, which converts the existing twisted-pair telephone lines into access paths for multimedia and high speed data communications. ADSL transmits more than 8 Mbps to a subscriber, and can reach 1Mbps from the subscriber to the central office. ADSL can literally transform the actual public information network by bringing movies, television, video catalogs, remote CD-ROMs, LANs, and the Internet into homes. An ADSL modem is connected to a twisted-pair telephone line, creating three information channels: a high speed downstream channel (up to 1.1MHz) depending on the implementation of the ADSL architecture, a medium speed upstream channel (up to 130kHz) and a POTS (Plain Old Telephone Service), split off from the modem by filters. The TS613 is used as a dual line driver for the upstream signal. For the remote terminal it is required to create an ADSL modem easy to plug in a PC. In such an application, the driver should be implemented with a +12 volts single power supply. This +12V supply is available on PCI connector of purchase. The figure 2 shows a single +12V supply circuit that uses the TS613 as a remote terminal transmitter in differential mode. Figure 2 : TS613 as a differential line driver with a +12V single supply 1µ 100n 3 +12V high output current digital treatment upstream impedance matching HYBRID CIRCUIT analog to digital 6/9 reception (analog) reception circuits twisted-pair telephone line downstream 1 12.5 10n 1:2 R2 47k Vo 25Ω R1 10µ Vi 100n Figure 1 : Typical ADSL Line Interface TS613 Line Driver +12V _ 47k 100n GND R3 6 _ 5 + Hybrid & Transformer 100Ω Vo 7 The Figure1 shows a typical analog line interface used for ADSL. The upstream and downstream signals are separated from the telephone line by using an hybrid circuit and a line transformer. On this note, the accent will be made on the emission path. digital to emission LPfilter analog (analog) 8 + 1k Vi 1k THE LINE INTERFACE - ADSL Remote Terminal (RT): 2 12.5 GND 4 The driver is biased with a mid supply (nominaly +6V), in order to maintain the DC component of the signal at +6V. This allows the maximum dynamic range between 0 and +12 V. Several options are possible to provide this bias supply (such as a virtual ground using an operational amplifier), such as a two-resistance divider which is the cheapest solution. A high resistance value is required to limit the current consumption. On the other hand, the current must be high enough to bias the inverting input of the TS613. If we consider this bias current (5µA) as the 1% of the current through the resistance divider (500µA) to keep a stable mid supply, two 47kΩ resistances can be used. The input provides two high pass filters with a break frequency of about 1.6kHz which is necessary to remove the DC component of the input signal. To avoid DC current flowing in the primary of the transformer, an output capacitor is used. The TS613 1µF capacitance provides a path for low frequencies, the 10nF capacitance provides a path for high end of the spectrum. Component calculation: Let us consider the equivalent circuit for a single ended configuration, figure4. In differential mode the TS613 is able to deliver a typical amplitude signal of 18V peak to peak. Figure 4 : Single ended equivalent circuit The dynamic line impedance is 100Ω. The typical value of the amplitude signal required on the line is up to 12.4V peak to peak. By using a 1:2 transformer ratio the reflected impedance back to the primary will be a quarter (25Ω) and therefore the amplitude of the signal required with this impedance will be the half (6.2 V peak to peak). Assuming the 25Ω series resistance (12.5Ω for both outputs) necessary for impedance matching, the output signal amplitude required is 12.4 V peak to peak. This value is acceptable for the TS613. In this case the load impedance is 25Ω for each driver. For the ADSL upstream path, a lowpass filter is absolutely necessary to cutoff the higher frequencies from the DAC analog output. In this simple non-inverting amplification configuration, it will be easy to implement a Sallen-Key lowpass filter by using the TS613. For ADSL over POTS, a maximum frequency of 135kHz is reached. For ADSL over ISDN, the maximum frequency will be 276kHz. INCREASING THE LINE LEVEL BY USING AN ACTIVE IMPEDANCE MATCHING With passive matching, the output signal amplitude of the driver must be twice the amplitude on the load. To go beyond this limitation an active maching impedance can be used. With this technique it is possible to keep good impedance matching with an amplitude on the load higher than the half of the ouput driver amplitude. This concept is shown in figure3 for a differential line. Figure 3 : TS613 as a differential line driver with an active impedance matching 3 +12V 2 8 + +12V 1k Vi 1 0µ 1k GND 25Ω _ 5 + 4 Vo° Vo R2 -1 R3 1/2R1 1/2 RL Let us consider the unloaded system. Assuming the currents through R1, R2 and R3 as respectively: 2V i ( V i – V o° ) (Vi + Vo) --------- , -------------------------- and -----------------------R1 R2 R3 As Vo° equals Vo without load, the gain in this case becomes : 2R 2 R2 1 + ----------- + ------V o ( noload ) R 1 R3 G = ------------------------------- = ---------------------------------Vi R2 1 – ------R3 The gain, for the loaded system will be (1): 2R 2 R2 1 + ----------- + ------1 R 1 R3 V o ( wi t hl oad ) GL = ------------------------------------ = --- ----------------------------------- ,( 1 ) 2 R2 Vi 1 – ------R3 As shown in figure5, this system is an ideal generator with a synthesized impedance as the internal impedance of the system. From this, the output voltage becomes: V o = ( V i G) – ( R oIout ) ,( 2 ) with Ro the synthesized impedance and Iout the output current. On the other hand Vo can be expressed as: Hybrid & Transformer 100Ω Vo R4 6 Vo° 7 100n 1:2 R5 47k 100n _ Vi Vo R3 R1 Vi 10n Vo° R2 47k 12.5 1 _ Rs1 2R 2 R2 V i 1 + ----------- + ------- R 1 R3 R s1 Iout V o = ---------------------------------------------- – --------------------- ,( 3 ) R2 R2 1 – ------1 – ------R3 R3 1µ 100n + 12.5 GND 7/9 TS613 By identification of both equations (2) and (3), the synthesized impedance is, with Rs1=Rs2=Rs: Rs R o = ----------------- ,( 4 ) R2 1 – ------R3 GL (gain for the loaded system) R1 R2 (=R4) R3 (=R5) Figure 5 : Equivalent schematic. Ro is the synthesized impedance Rs GL is fixed for the application requirements GL=Vo/Vi=0.5(1+2R2/R1+R2/R3)/(1-R2/R3) 2R2/[2(1-R2/R3)GL-1-R2/R3] Abritrary fixed R2/(1-Rs/0.5RL) 0.5RL(k-1) CAPABILITIES Ro Iout Vi.Gi 1/2RL The table below shows the calculated components for different values of k. In this case R2=1000Ω and the gain=16dB. The last column displays the maximum amplitude level on the line regarding the TS613 maximum output capabilities (18Vpp diff.) and a 1:2 line transformer ratio. Active matching Unlike the level Vo° required for a passive impedance, Vo° will be smaller than 2Vo in our case. Let us write Vo°=kVo with k the matching factor varying between 1 and 2. Assuming that the current through R3 is negligeable, it comes the following resistance divider: k V oR L R o = --------------------------R L + 2R s1 After choosing the k factor, Rs will equal to 1/2RL(k-1). A good impedance matching assumes: 1 R o = --- R L ,( 5 ) 2 From (4) and (5) it becomes: 2R s R2 ------- = 1 – ---------- , ( 6 ) RL R3 By fixing an arbitrary value for R2, (6) gives: R2 R3 = ------------------2R s 1 – ---------RL Finally, the values of R2 and R3 allow us to extract R1 from (1), and it comes: 2R 2 R 1 = --------------------------------------------------------- ,( 7) R2 R2 2 1 – ------- GL – 1 – ------ R3 R3 with GL the required gain. 8/9 k R1 (Ω) R3 (Ω) Rs (Ω) 1.3 1.4 1.5 1.6 820 490 360 270 1500 1600 2200 2400 3.9 5.1 6.2 7.5 1.7 240 3300 9.1 Passive matching TS613 Output Level to get 12.4Vpp on the line (Vpp diff) 8 8.7 9.3 9.9 10.5 12.4 Maximum Line level (Vpp diff) 27.5 25.7 25.3 23.7 22.3 18 MEASUREMENT OF THE POWER CONSUMPTION IN THE ADSL APPLICATION Conditions: Passive impedance matching Transformer turns ratio: 2 Maximun level required on the line: 12.4Vpp Maximum output level of the driver: 12.4Vpp Crest factor: 5.3 (Vp/Vrms) The TS613 power consumption during emission on 900 and 4550 meter twisted pair telephone lines: 360mW TS613 PACKAGE MECHANICAL DATA 8 PINS - PLASTIC MICROPACKAGE (SO) Millimeters Inches Dim. Min. A a1 a2 a3 b b1 C c1 D E e e3 F L M S Typ. Max. 0.65 0.35 0.19 0.25 1.75 0.25 1.65 0.85 0.48 0.25 0.5 4.8 5.8 5.0 6.2 0.1 Min. Typ. Max. 0.026 0.014 0.007 0.010 0.069 0.010 0.065 0.033 0.019 0.010 0.020 0.189 0.228 0.197 0.244 0.004 45° (typ.) 1.27 0.050 3.81 3.8 0.4 0.150 4.0 1.27 0.6 0.150 0.016 0.157 0.050 0.024 8° (max.) Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibil ity for the consequences of use of such information nor for any infring ement of patents or other righ ts of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change witho ut notice. This publ ication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life suppo rt devices or systems withou t express written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics 2000 STMicroelectronics - Printed in Italy - All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia - Malta - Morocco Singapore - Spain - Sweden - Switzerland - United Kingdom http://www. st.com 9/9