3 V LVDS Quad CMOS Differential Line Receiver ADN4668 ±15 kV ESD protection on receiver input pins 400 Mbps (200 MHz) switching rates Flow-through pin configuration simplifies PCB layout 150 ps channel-to-channel skew (typical) 100 ps differential skew (typical) 2.7 ns maximum propagation delay 3.3 V power supply High impedance outputs on power-down Low power design (3 mW quiescent typical) Interoperable with existing 5 V LVDS drivers Accepts small swing (310 mV typical) differential input signal levels Supports open, short, and terminated input fail-safe 0 V to −100 mV threshold region Conforms to TIA/EIA-644 LVDS standard Industrial operating temperature range of −40°C to +85°C Available in 16-lead surface-mount SOIC and 16-lead low profile TSSOP package FUNCTIONAL BLOCK DIAGRAM VCC ADN4668 RIN1+ RIN1– RIN2+ RIN2– RIN3+ RIN3– RIN4+ RIN4– R1 ROUT1 R2 ROUT2 R3 ROUT3 R4 ROUT4 EN EN GND 07237-001 FEATURES Figure 1. APPLICATIONS Point-to-point data transmission Multidrop buses Clock distribution networks Backplane receivers GENERAL DESCRIPTION The ADN4668 is a quad-channel CMOS, low voltage differential signaling (LVDS) line receiver offering data rates of over 400 Mbps (200 MHz) and ultralow power consumption. It features a flowthrough pin configuration for easy PCB layout and separation of input and output signals. The device accepts low voltage (310 mV typical) differential input signals and converts them to a single-ended, 3 V TTL/CMOS logic level. The ADN4668 also offers active-high and active-low enable/disable inputs (EN and EN) that control all four receivers. They disable the receivers and switch the outputs to a high impedance state. This high impedance state allows the outputs of one or more ADN4668s to be multiplexed together and reduces the quiescent power consumption to 3 mW typical. The ADN4668 and its companion driver, the ADN4667, offer a new solution to high speed, point-to-point data transmission and a low power alternative to emitter-coupled logic (ECL) or positive emitter-coupled logic (PECL). 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 from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2008 Analog Devices, Inc. All rights reserved. ADN4668 TABLE OF CONTENTS Features .............................................................................................. 1 ESD Caution...................................................................................6 Applications ....................................................................................... 1 Pin Configuration and Function Descriptions..............................7 Functional Block Diagram .............................................................. 1 Typical Performance Characteristics ..............................................8 General Description ......................................................................... 1 Theory of Operation ...................................................................... 11 Revision History ............................................................................... 2 Enable Inputs .............................................................................. 11 Specifications..................................................................................... 3 Applications Information .......................................................... 11 AC Characteristics........................................................................ 4 Outline Dimensions ....................................................................... 12 Test Circuits and Waveforms ...................................................... 4 Ordering Guide .......................................................................... 12 Absolute Maximum Ratings............................................................ 6 REVISION HISTORY 7/08—Rev. 0 to Rev. A Added 16-Lead SOIC_N.................................................... Universal Changes to Table 1 ............................................................................ 3 Updated Outline Dimensions ....................................................... 12 Changes to Ordering Guide .......................................................... 12 3/08—Revision 0: Initial Version Rev. A | Page 2 of 12 ADN4668 SPECIFICATIONS VDD = 3.0 V to 3.6 V, CL = 15 pF to GND, all specifications TMIN to TMAX, unless otherwise noted. 1, 2 Table 1. Parameter LVDS INPUTS (RINx+, RINx−) Differential Input High Threshold, VTH at RINx+, RINx− 3 Differential Input Low Threshold, VTL at RINx+, RINx−3 Common-Mode Voltage Range, VCMR at RINx+, RINx− 4 Input Current, IIN at RINx+, RINx− LOGIC INPUTS Input High Voltage, VIH Input Low Voltage, VIL Input Current, IIN Input Clamp Voltage, VCL OUTPUTS (ROUTx) Output High Voltage, VOH Output Low Voltage, VOL Output Short-Circuit Current, IOS 5 Output Off State Current, IOZ POWER SUPPLY No Load Supply, Current Receivers Enabled, ICC No Load Supply, Current Receivers Disabled, ICCZ ESD PROTECTION RINx+, RINx− Pins All Pins Except RINx+, RINx− Min −100 0.1 −10 −10 −20 2.0 GND −10 −1.5 2.7 2.7 2.7 −15 −10 Typ Max Unit Conditions/Comments −35 −35 0 mV mV V μA μA μA VCM = 1.2 V, 0.05 V, 2.95 V VCM = 1.2 V, 0.05 V, 2.95 V VID = 200 mV p-p VIN = 2.8 V, VCC = 3.6 V or 0 V VIN = 0 V, VCC = 3.6 V or 0 V VIN = 3.6 V, VCC = 0 V V V μA V VIN = 0 V or VCC, other input = VCC or GND ICL = −18 mA IOH = −0.4 mA, VID = 200 mV IOH = −0.4 mA, input terminated IOH = −0.4 mA, input shorted IOL = 2 mA, VID = −200 mV Enabled, VOUT = 0 V Disabled, VOUT = 0 V or VCC ±5 ±1 ±1 ±5 −0.8 2.3 +10 +10 +20 VCC 0.8 +10 3.3 3.3 3.3 0.05 −47 ±1 0.25 −100 +10 V V V V V μA 12 1 15 5 mA mA EN = VCC, inputs open EN = GND, inputs open kV kV Human body model Human body model ±15 ±3.5 1 Current-into-device pins are defined as positive. Current-out-of-device pins are defined as negative. All voltages are referenced to ground, unless otherwise specified. All typicals are given for VCC = 3.3 V and TA = 25°C. 3 VCC is always higher than the RINx+ and RINx− voltage. RINx− and RINx+ have a voltage range of −0.2 V to VCC − VID/2. However, to be compliant with ac specifications, the common voltage range is 0.1 V to 2.3 V. 4 VCMR is reduced for larger VID. For example, if VID = 400 mV, VCMR is 0.2 V to 2.2 V. The fail-safe condition with inputs shorted is not supported over the common-mode range of 0 V to 2.4 V but is supported only with inputs shorted and no external common-mode voltage applied. VID up to VCC − 0 V can be applied to the RINx+/RINx− inputs with the common-mode voltage set to VCC/2. Propagation delay and differential pulse skew decrease when VID is increased from 200 mV to 400 mV. Skew specifications apply for 200 mV ≤ VID ≤ 800 mV over the common-mode range. 5 Output short-circuit current (IOS) is specified as magnitude only; a minus sign indicates direction only. Only one output should be shorted at a time; do not exceed the maximum junction temperature specification. 2 Rev. A | Page 3 of 12 ADN4668 AC CHARACTERISTICS VDD = 3.0 V to 3.6 V, CL = 15 pF to GND, all specifications TMIN to TMAX, unless otherwise noted. 1, 2, 3, 4 Table 2. Parameter 5 Differential Propagation Delay, High-to-Low, tPHLD Differential Propagation Delay, Low-to-High, tPLHD Differential Pulse Skew |tPHLD − tPLHD|, tSKD1 8 Differential Channel-to-Channel Skew, Same Device, tSKD23 Differential Part-to-Part Skew, tSKD34 Differential Part-to-Part Skew, tSKD4 9 Rise Time, tTLH Fall Time, tTHL Disable Time, High-to-Z, tPHZ Disable Time, Low-to-Z, tPLZ Enable Time, Z-to-High, tPZH Enable Time, Z-to-Low, tPZL Maximum Operating Frequency, fMAX 10 Min 1.2 1.2 0 0 Typ 2.0 1.9 0.1 0.15 200 0.5 0.35 8 8 9 9 250 Max 2.7 2.7 0.4 0.5 1.0 1.5 1.0 1.0 14 14 14 14 Conditions/Comments 6 CL = 15 pF, 7 VID = 200 mV, see Figure 2 and Figure 3 CL = 15 pF,7 VID = 200 mV, see Figure 2 and Figure 3 CL = 15 pF,7 VID = 200 mV, see Figure 2 and Figure 3 CL = 15 pF,7 VID = 200 mV, see Figure 2 and Figure 3 CL = 15 pF,7 VID = 200 mV, see Figure 2 and Figure 3 CL = 15 pF,7 VID = 200 mV, see Figure 2 and Figure 3 CL = 15 pF,7 VID = 200 mV, see Figure 2 and Figure 3 CL = 15 pF,7 VID = 200 mV, see Figure 2 and Figure 3 RL = 2 kΩ, CL = 15 pF,7 see Figure 4 and Figure 5 RL = 2 kΩ, CL = 15 pF,7 see Figure 4 and Figure 5 RL = 2 kΩ, CL = 15 pF,7 see Figure 4 and Figure 5 RL = 2 kΩ, CL = 15 pF,7 see Figure 4 and Figure 5 All channels switching Unit ns ns ns ns ns ns ns ns ns ns ns ns MHz 1 All typicals are given for VCC = 3.3 V and TA = 25°C. Generator waveform for all tests, unless otherwise specified: f = 1 MHz, ZO = 50 Ω, and tR and tF (0% to 100%) ≤ 3 ns for RINx+/RINx−. 3 Channel-to-channel skew, tSKD2, is defined as the difference between the propagation delay of one channel and that of the others on the same chip with any event on the inputs. 4 Part-to-part skew, tSKD3, is the differential channel-to-channel skew of any event between devices. This specification applies to devices at the same VCC and within 5°C of each other within the operating temperature range. 5 AC parameters are guaranteed by design and characterization. 6 Current-into-device pins are defined as positive. Current-out-of-device pins are defined as negative. All voltages are referenced to ground, unless otherwise specified. 7 CL includes probe and jig capacitance. 8 tSKD1 is the magnitude difference in the differential propagation delay time between the positive-going edge and the negative-going edge of the same channel. 9 Part-to-part skew, tSKD4, is the differential channel-to-channel skew of any event between devices. This specification applies to devices over the recommended operating temperature and voltage ranges and across process distribution. tSKD4 is defined as |maximum − minimum| differential propagation delay. 10 fMAX generator input conditions: f = 200 MHz, tR = tF < 1 ns (0% to 100%), 50% duty cycle, differential (1.05 V p-p to 1.35 V p-p). Output criteria: 60%/40% duty cycle, VOL (maximum = 0.4 V), VOH (minimum = 2.7 V), CL = 15 pF (stray plus probes). 2 TEST CIRCUITS AND WAVEFORMS VCC RINx+ SIGNAL GENERATOR ROUTx RINx– 50Ω 50Ω CL 07237-002 RECEIVER IS ENABLED CL = LOAD AND TEST JIG CAPACITANCE Figure 2. Test Circuit for Receiver Propagation Delay and Transition Time RINx– 1.3V 0V (DIFFERENTIAL) VID = 200mV 1.2V RINx+ 1.1V tPLHD tPHLD VOH 80% 1.5V 1.5V 20% 20% tTLH tTHL VOL Figure 3. Receiver Propagation Delay and Transition Time Waveforms Rev. A | Page 4 of 12 07237-003 ROUTx 80% ADN4668 VCC S1 RL RINx+ ROUTx CL RINx– EN SIGNAL GENERATOR 50Ω EN NOTES 1. CL INCLUDES LOAD AND TEST JIG CAPACITANCE. 2. S1 CONNECTED TO VCC FOR tPZL AND tPLZ MEASUREMENTS. 3. S1 CONNECTED TO GND FOR tPZH AND tPHZ MEASUREMENTS. 07237-004 GND Figure 4. Test Circuit for Receiver Enable/Disable Delay 3V EN WITH EN = GND OR OPEN CIRCUIT 1.5V 1.5V 0V 3V EN WITH EN = VCC 1.5V 1.5V 0V tPHZ 0.5V tPZH VOH 50% ROUTx WITH VID = +100mV GND VCC ROUTx WITH VID = –100mV 0.5V tPLZ tPZL Figure 5. Receiver Enable/Disable Delay Waveforms Rev. A | Page 5 of 12 VOL 07237-005 50% ADN4668 ABSOLUTE MAXIMUM RATINGS TA = 25°C, unless otherwise noted. Table 3. Parameter VCC to GND Input Voltage (RINx+, RINx−) to GND Enable Input Voltage (EN, EN) to GND Output Voltage (ROUTx) to GND Operating Temperature Range Industrial Storage Temperature Range Junction Temperature (TJ MAX) Power Dissipation Thermal Impedance, θJA TSSOP Package SOIC Package Reflow Soldering Peak Temperature Pb-Free Rating −0.3 V to +4 V −0.3 V to VCC + 0.3 V −0.3 V to VCC + 0.3 V −0.3 V to VCC + 0.3 V Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. −40°C to +85°C −65°C to +150°C 150°C (TJ MAX − TA)/θJA ESD CAUTION 150.4°C/W 125°C/W ± 5°C 260°C ± 5°C Rev. A | Page 6 of 12 ADN4668 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS 16 EN RIN1– 1 RIN1+ 2 15 ROUT1 RIN2+ 3 ADN4668 14 ROUT2 RIN2– 4 TOP VIEW (Not to Scale) RIN3– 5 RIN3+ 6 11 ROUT3 RIN4+ 7 10 ROUT4 RIN4– 8 9 13 VCC EN 07237-006 12 GND Figure 6. Pin Configuration Table 4. Pin Function Descriptions Pin No. 1 Mnemonic RIN1− 2 RIN1+ 3 RIN2+ 4 RIN2− 5 RIN3− 6 RIN3+ 7 RIN4+ 8 RIN4− 9 EN 10 ROUT4 11 ROUT3 12 13 14 GND VCC ROUT2 15 ROUT1 16 EN Description Receiver Channel 1 Inverting Input. When this input is more negative than RIN1+, ROUT1 is high. When this input is more positive than RIN1+, ROUT1 is low. Receiver Channel 1 Noninverting Input. When this input is more positive than RIN1−, ROUT1 is high. When this input is more negative than RIN1−, ROUT1 is low. Receiver Channel 2 Noninverting Input. When this input is more positive than RIN2−, ROUT2 is high. When this input is more negative than RIN2−, ROUT2 is low. Receiver Channel 2 Inverting Input. When this input is more negative than RIN2+, ROUT2 is high. When this input is more positive than RIN2+, ROUT2 is low. Receiver Channel 3 Inverting Input. When this input is more negative than RIN3+, ROUT3 is high. When this input is more positive than RIN3+, ROUT3 is low. Receiver Channel 3 Noninverting Input. When this input is more positive than RIN3−, ROUT3 is high. When this input is more negative than RIN3−, ROUT3 is low. Receiver Channel 4 Noninverting Input. When this input is more positive than RIN4−, ROUT4 is high. When this input is more negative than RIN4−, ROUT4 is low. Receiver Channel 4 Inverting Input. When this input is more negative than RIN4+, ROUT4 is high. When this input is more positive than RIN4+, ROUT4 is low. Active-Low Enable and Power-Down Input with Pull-Down (3 V TTL/CMOS). When EN is held high, EN enables the receiver outputs when EN is low or open circuit and puts the receiver outputs into a high impedance state and powers down the device when EN is high. Receiver Channel 4 Output (3 V TTL/CMOS). If the differential input voltage between RIN4+ and RIN4− is positive, this output is high. If the differential input voltage is negative, this output is low. Receiver Channel 3 Output (3 V TTL/CMOS). If the differential input voltage between RIN3+ and RIN3− is positive, this output is high. If the differential input voltage is negative, this output is low. Ground Reference Point for All Circuitry on the Part. Power Supply Input. These parts can be operated from 3.0 V to 3.6 V. Receiver Channel 2 Output (3 V TTL/CMOS). If the differential input voltage between RIN2+ and RIN2− is positive, this output is high. If the differential input voltage is negative, this output is low. Receiver Channel 1 Output (3 V TTL/CMOS). If the differential input voltage between RIN1+ and RIN1− is positive, this output is high. If the differential input voltage is negative, this output is low. Active-High Enable and Power-Down Input (3 V TTL/CMOS). When EN is held low or open circuit, EN enables the receiver outputs when EN is high and puts the receiver outputs into a high impedance state and powers down the device when EN is low. Rev. A | Page 7 of 12 ADN4668 TYPICAL PERFORMANCE CHARACTERISTICS –0.06 ILOAD = –400µA TA = 25°C VID = 200mV 3.5 OUTPUT TRISTATE CURRENT, IOS (nA) 3.4 3.3 3.2 3.1 3.0 VOUT = 0V TA = 25°C –0.07 –0.08 –0.09 –0.10 –0.11 –0.12 –0.13 –0.14 –0.15 3.0 3.1 3.2 3.3 3.4 3.5 3.6 POWER SUPPLY VOLTAGE, VCC (V) 07237-007 2.9 3.0 3.1 3.2 3.3 3.4 3.5 3.6 POWER SUPPLY VOLTAGE, VCC (V) Figure 7. Output High Voltage, VOH vs. Power Supply Voltage, VCC Figure 10. Output Tristate Current, IOS vs. Power Supply Voltage, VCC 0 ILOAD = 2µA TA = 25°C VID = –200mV 33.55 VOUT = 0V TA = 25°C –5 THRESHOLD VOLTAGE, VTH (mV) OUTPUT LOW VOLTAGE, VOL (mV) 33.60 33.50 33.45 33.40 33.35 –10 –15 –20 –25 –30 –35 –40 –45 33.30 3.2 3.3 3.4 3.5 3.6 3.1 3.2 3.3 3.4 3.5 3.6 POWER SUPPLY VOLTAGE, VCC (V) Figure 8. Output Low Voltage, VOL vs. Power Supply Voltage, VCC Figure 11. Threshold Voltage, VTH vs. Power Supply Voltage, VCC –35 100 VOUT = 0V TA = 25°C –37 90 POWER SUPPLY CURRENT, ICC (mA) OUTPUT SHORT-CIRCUIT CURRENT, I OS (mA) POWER SUPPLY VOLTAGE, VCC (V) 3.0 –39 –41 –43 –45 –47 –49 –51 –53 80 70 ALL CHANNELS SWITCHING 60 50 40 30 20 10 –55 3.1 3.2 3.3 3.4 POWER SUPPLY VOLTAGE, VCC (V) 3.5 3.6 07237-009 3.0 0 10k ONE CHANNEL SWITCHING 100k 1M 10M 100M BIT RATE (bps) Figure 9. Output Short-Circuit Current, IOS vs. Power Supply Voltage, VCC Rev. A | Page 8 of 12 Figure 12. Power Supply Current, ICC vs. Bit Rate 1G 07237-012 3.1 07237-008 3.0 07237-011 –50 33.25 07237-010 OUTPUT HIGH VOLTAGE, VOH (V) 3.6 ADN4668 2.40 92.0 91.5 91.0 90.5 90.0 –40 –15 10 35 60 TA = 25°C VID = 200mV FREQ = 200MHz CL = 15pF 2.35 2.30 2.25 2.20 tPHLD 2.15 2.10 tPLHD 2.05 2.00 1.95 3.0 85 07237-016 92.5 DIFFERENTIAL PROPAGATION DELAY, tPLHD , tPHLD (ns) VCC = 3.3V VID = 200mV FREQ = 200MHz ALL CHANNELS SWITCHING 93.0 07237-022 POWER SUPPLY CURRENT, ICC (mA) 93.5 3.1 AMBIENT TEMPERATURE, TA (°C) Figure 13. Power Supply Current, ICC vs. Ambient Temperature, TA 3.5 3.6 tPHLD 2.20 tPLHD 2.15 2.10 2.05 –15 10 35 60 6 5 4 3 tPLHD 2 tPHLD 1 0 85 TA = 25°C FREQ = 200MHz VCM = 1.2V CL = 15pF 7 07237-017 2.25 DIFFERENTIAL PROPAGATION DELAY, tPLHD , tPHLD (ns) 2.30 07237-014 0 AMBIENT TEMPERATURE, TA (°C) 500 1000 1500 2000 2500 3000 DIFFERENTIAL INPUT VOLTAGE, VID (mV) Figure 14. Differential Propagation Delay, tPLHD, tPHLD vs. Ambient Temperature, TA Figure 17. Differential Propagation Delay, tPLHD, tPHLD vs. Differential Input Voltage, VID 4.0 200 TA = 25°C FREQ = 200MHz VID = 200mV CL = 15pF DIFFERENTIAL SKEW, tSKD (ps) 3.5 150 3.0 2.5 tPLHD 2.0 07237-015 tPHLD 0 0.5 1.0 1.5 2.0 2.5 3.0 COMMON-MODE VOLTAGE, VCM (V) 100 TA = 25°C VID = 200mV FREQ = 200MHz CL = 15pF 50 0 –50 –100 –150 –200 3.0 07237-018 DIFFERENTIAL PROPAGATION DELAY, tPLHD , tPHLD (ns) 3.4 8 VCC = 3.3V VID = 200mV FREQ = 200MHz CL = 15pF 2.00 –40 DIFFERENTIAL PROPAGATION DELAY, tPLHD , tPHLD (ns) 3.3 Figure 16. Differential Propagation Delay, tPLHD, tPHLD vs. Power Supply Voltage, VCC 2.35 1.5 3.2 POWER SUPPLY VOLTAGE, VCC (V) 3.1 3.2 3.3 3.4 3.5 3.6 POWER SUPPLY VOLTAGE, VCC (V) Figure 15. Differential Propagation Delay, tPLHD, tPHLD vs. Common-Mode Voltage, VCM Figure 18. Differential Skew, tSKD vs. Power Supply Voltage, VCC Rev. A | Page 9 of 12 ADN4668 80 20 0 –20 –40 –80 –40 07237-019 –60 –15 10 35 60 TA = 25°C VID = 200mV FREQ = 25MHz CL = 15pF TRANSITION TIME, tTLH, tTHL (ps) 510 500 tTHL 480 07237-020 470 460 3.0 3.1 3.2 3.3 3.4 tTLH 500 490 480 470 tTHL –15 10 35 60 80 Figure 21. Transition Time, tTLH, tTHL vs. Ambient Temperature, TA 520 490 510 AMBIENT TEMPERATURE, TA (°C) 550 530 520 450 –40 85 Figure 19. Differential Skew, tSKD vs. Ambient Temperature, TA tTLH 530 460 AMBIENT TEMPERATURE, TA (°C) 540 540 VCC = 3.3V VID = 200mV FREQ = 25MHz CL = 15pF 07237-021 40 550 TRANSITION TIME, tTLH, tTHL (ps) DIFFERENTIAL SKEW, tSKD (ps) 60 560 VCC = 3.3V VID = 200mV FREQ = 200MHz CL = 15pF 3.5 3.6 POWER SUPPLY VOLTAGE, VCC (V) Figure 20. Transition Time, tTLH, tTHL vs. Power Supply Voltage, VCC Rev. A | Page 10 of 12 ADN4668 THEORY OF OPERATION The ADN4668 is a quad-channel line receiver for low voltage differential signaling. It takes a differential input signal of 310 mV typical and converts it into a single-ended 3 V TTL/ CMOS logic signal. A differential current input signal, received via a transmission medium such as a twisted pair cable, develops a voltage across a terminating resistor, RT. This resistor is chosen to match the characteristic impedance of the medium, typically around 100 Ω. The differential voltage is detected by the receiver and converted back into a single-ended logic signal. When the noninverting receiver input, RINx+, is positive with respect to the inverting input, RINx− (current flows through RT from RINx+ to RINx−), ROUTx is high. When the noninverting receiver input, RIN+, is negative with respect to the inverting input, RINx− (current flows through RT from RINx− to RINx+), ROUTx is low. Using the ADN4667 as a driver, the received differential current is between ±2.5 mA and ±4.5 mA (±3.1 mA typical), developing between ±250 mV and ±450 mV across a 100 Ω termination resistor. The received voltage is centered on the receiver offset of 1.2 V. The noninverting receiver input is typically (1.2 V + [310 mV/2]) = 1.355 V, and the inverting receiver input is (1.2 V − [310 mV/2]) = 1.045 V for Logic 1. For Logic 0, the inverting and noninverting input voltages are reversed. Note that because the differential voltage reverses polarity, the peak-topeak voltage swing across RT is twice the differential voltage. Current-mode signaling offers considerable advantages over voltage-mode signaling, such as the RS-422. The operating current remains fairly constant with increased switching frequency, whereas the operating current of voltage-mode drivers increases exponentially in most cases. This increase is caused by the overlap as internal gates switch between high and low, causing currents to flow from VCC to ground. A currentmode device reverses a constant current between its two outputs, with no significant overlap currents. This is similar to emitter-coupled logic (ECL) and positive emittercoupled logic (PECL), but without the high quiescent current of ECL and PECL. ENABLE INPUTS The ADN4668 has active-high and active-low enable inputs that put all the logic outputs into a high impedance state when disabled, reducing device current consumption from 9 mA typical to 1 mA typical. See Table 5 for a truth table of the enable inputs. Table 5. Enable Inputs Truth Table EN EN High Low or Open High Low or Open Any other combination of EN and EN RINx+ RINx− ROUTx 1.045 V 1.355 V X 1.355 V 1.045 V X 0 1 High-Z APPLICATIONS INFORMATION Figure 22 shows a typical application for point-to-point data transmission using the ADN4667 as the driver and the ADN4668 as the receiver. 1/4 ADN4667 1/4 ADN4668 EN EN EN EN RINx+ RT 100Ω DIN DOUTy– GND DOUT RINx– GND Figure 22. Typical Application Circuit Rev. A | Page 11 of 12 07237-023 DOUTy+ ADN4668 OUTLINE DIMENSIONS 10.00 (0.3937) 9.80 (0.3858) 4.00 (0.1575) 3.80 (0.1496) 9 16 1 6.20 (0.2441) 5.80 (0.2283) 8 1.27 (0.0500) BSC 0.25 (0.0098) 0.10 (0.0039) COPLANARITY 0.10 0.50 (0.0197) 0.25 (0.0098) 1.75 (0.0689) 1.35 (0.0531) SEATING PLANE 0.51 (0.0201) 0.31 (0.0122) 45° 8° 0° 0.25 (0.0098) 0.17 (0.0067) 1.27 (0.0500) 0.40 (0.0157) COMPLIANT TO JEDEC STANDARDS MS-012-AC 060606-A 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 23. 16-Lead Standard Small Outline Package [SOIC_N] (R-16) Dimensions shown in millimeters and (inches) 5.10 5.00 4.90 16 9 4.50 4.40 4.30 6.40 BSC 1 8 PIN 1 1.20 MAX 0.15 0.05 0.30 0.19 0.65 BSC COPLANARITY 0.10 0.20 0.09 SEATING PLANE 8° 0° 0.75 0.60 0.45 COMPLIANT TO JEDEC STANDARDS MO-153-AB Figure 24. 16-Lead Thin Shrink Small Outline Package [TSSOP] (RU-16) Dimensions shown in millimeters ORDERING GUIDE Model ADN4668ARZ 1 ADN4668ARZ-REEL71 ADN4668ARUZ1 ADN4668ARUZ-REEL71 1 Temperature Range −40°C to +85°C −40°C to +85°C −40°C to +85°C −40°C to +85°C Package Description 16-Lead Standard Small Outline Package [SOIC_N] 16-Lead Standard Small Outline Package [SOIC_N] 16-Lead Thin Shrink Small Outline Package [TSSOP] 16-Lead Thin Shrink Small Outline Package [TSSOP] Z = RoHS Compliant Part. ©2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07237-0-7/08(A) Rev. A | Page 12 of 12 Package Option R-16 R-16 RU-16 RU-16