ADN2891 Analog Devices, Inc., ADN2891 Datasheet
ADN2891
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ADN2891 Summary of contents
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... The on-chip RSSI detector facilitates SFF-8472- compliant optical transceivers by eliminating the need for external RSSI detector circuitry. Additional features include a programmable loss-of-signal (LOS) detector and output squelch. The ADN2891 is available × 3 mm, 16-lead LFCSP. FUNCTIONAL BLOCK DIAGRAM AVCC AVEE DRVCC ...
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... ADN2891 TABLE OF CONTENTS Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 Thermal Resistance ...................................................................... 5 ESD Caution.................................................................................. 5 Pin Configuration and Function Descriptions............................. 6 Typical Performance Characteristics ............................................. 7 Theory of Operation ...................................................................... 10 Limiting Amplifier ..................................................................... 10 REVISION HISTORY 7/05—Rev Rev. A Changes to Table 1............................................................................ 3 Changes to Ordering Guide .......................................................... 13 3/05—Revision 0: Initial Version Loss of Signal (LOS) Detector .................................................. 10 Received Signal Strength Indicator (RSSI) ...
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... Measured at PD_CATHODE, with μ 3.3 3 +25 +95 °C T MIN 50 Ω Single-ended 660 850 mV p-p Differential 80 130 ps 20% to 80% Rev Page ADN2891 23 −10 − 1, BER ≤ − − 100 kΩ kΩ 23 − − 1 ≤ 1000 μ MAX ...
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... ADN2891 Parameter Min LOGIC INPUTS (SQUELCH Input High Voltage 2 Input Low Voltage IL Input Current LOGIC OUTPUTS (LOS Output High Voltage 2 Output Low Voltage OL Typ Max Unit Test Conditions/Comments V 0 μA I INH 6 μA I INL V Open drain output, 4.7 kΩ kΩ ...
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... THERMAL RESISTANCE J-STD-20 θ is specified for 4-layer PCB with exposed paddle soldered JA 125°C to GND. Table 3. Package Type 3 mm × 3 mm, 16-lead LFCSP Rev Page ADN2891 θ Unit JA 28 °C/W ...
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... PD_VCC P 16 PD_CATHODE AO Exposed Pad P Pad power digital input digital output analog input; and AO = analog output AVCC DRVCC 1 12 ADN2891 PIN OUTP 2 11 TOP VIEW NIN OUTN 3 10 (Not to Scale) AVEE DRVEE Figure 2. Pin Configuration ...
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... Figure 4. Eye of ADN2891 @ 25°C, 3.2 Gbps, and 500 mV Input 50ps/DIV Figure 5. Eye of ADN2891 @ 95°C, 3.2 Gbps, and 10 mV Input Figure 6. Eye of ADN2891 @ 95°C, 3.2 Gbps, and 500 mV Input Figure 7. Eye of ADN2891 @ 25°C, 155 Mbps, and 10 mV Input Rev Page ADN2891 50ps/DIV 1ns/DIV ...
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... ADN2891 70 60 –40°C 50 +95°C +25°C 40 +95°C 30 +25°C DEASSERTION 20 –40°C 10 ASSERTION 0 1k 10k R (Ω) TH Figure 8. LOS Trip and Release vs 10k R (Ω) TH Figure 9. LOS Electrical Hysteresis vs 6.0 6.3 6.6 6.9 7.2 7.5 7.8 ELECTRICAL HYSTERESIS (dB) Figure 10. Sample Lot Distribution— ...
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... TEMPERATURE (°C) Output and PD_CATHODE (Input) Current of 5 μA +100°C +30°C 200 400 600 800 PD_CATHODE CURRENT (μA) Figure 18. RSSI Linearity % vs. PD_CATHODE Current –40 – TEMPERATURE (°C) Figure 19. ADN2891 I Current vs. Temperature CC 80 100 –40°C 1000 100 120 ...
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... Additionally, TIA output offset drifts may degrade receiver performance. The ADN2891 limiting amplifier is a high gain device susceptible to dc offsets in the signal path. The pulse width distortion presented in the NRZ data or a distortion generated by the TIA may appear as dc offset or a corrupted signal to the ADN2891 inputs ...
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... C1–C4, C11: 0.01μF X5R/X7R DIELECTRIC, 0201 CASE C5, C7, C9, C10, C12: 0.1μF X5R/X7R DIELECTRIC, 0402 CASE C6, C8: 1nF X5R/X7R DIELECTRIC, 0201 CASE C11 R3 4.7kΩ TO 10kΩ C12 R2 ON HOST BOARD VCC Rev Page RSSI MEASUREMENT TO ADC C10 VCC HOST BOARD C4 ADN2891 ...
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... ADN2891 PCB Layout Figure 21 shows the recommended PCB layout. The 50 Ω transmission lines are the traces that bring the high frequency input and output signals (PIN, NIN, OUTP, and OUTN) to the SMA connectors with minimum reflection. To avoid a signal skew between the differential traces, each differential PIN/NIN and OUTP/OUTN pair should have matched trace lengths from the signal pins to the corresponding SMA connectors ...
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... Body, Very Thin Quad (CP-16-3) Dimensions shown in millimeters Package Description 16-Lead VQ_LFCSP, 500 pieces 16-Lead VQ_LFCSP, 1,500 pieces 16-Lead VQ_LFCSP, 5,000 pieces Evaluation Board Rev Page 0.50 0.40 0. 1.35 EXPOSED PAD 9 (BOTTOM VIEW 0.25 MIN Package Option CP-16-3 CP-16-3 CP-16-3 ADN2891 Branding F04 F04 F04 ...
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... ADN2891 NOTES Rev Page ...
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... NOTES Rev Page ADN2891 ...
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... ADN2891 NOTES © 2005 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05244–0–7/05(A) Rev Page ...