Micrel, Inc. 5V/3.3V 3.2Gbps HIGH-SPEED LIMITING POST AMPLIFIER DESCRIPTION FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ SY88993V SY88993V > 3.2Gbps operation 3.3V or 5V power supply option Low noise CML data outputs Chatter-Free LOS generation Open Collector TTL LOS output TTL /EN Input Differential PECL inputs for data Single power supply Available in a tiny 10-pin (3mm) MSOP The SY88993V limiting post amplifier with its high and wide bandwidth is ideal for use as a post amplifier in fiberoptic receivers with data rates up to 3.2Gbps. Signals as small as 4mVPP can be amplified to drive devices with CML inputs. The SY88993V generates a chatter-free Loss of Signal (LOS) open collector TTL output. The SY88993V incorporates a programmble level detect function to identify when the input signal has been lost. This information can be fed back to the /EN input of the device to maintain stability under loss of signal conditions. Using LOSLVL pin the sensitivity of the level detect can be adjusted. The LOSLVL voltage can be set by connecting a resistor divider between VCC and VREF, Figure 2. APPLICATIONS ■ ■ ■ ■ ■ BLOCK DIAGRAM 1.25Gbps Gigabit Ethernet 531Mbps and 1062Mbps Fibre Channel 622Mbps SONET Gigabit interface converter 2.5Gbps SDH/SONET DIN Limiting Amplifer DOUT CML Buffer /DIN /DOUT VREF Enable VCC GND Level Detect LOS LOSLVL M9999-082205 [email protected] or (408) 955-1690 Rev.: C 1 /EN Amendment: /0 Issue Date: August 2005 Micrel, Inc. SY88993V PACKAGE/ORDERING INFORMATION Ordering Information /EN 1 Part Number Package Type Operating Range Package Marking Lead Finish SY88993VKC K10-1 Commercial 993V Sn-Pb SY88993VKCTR(1) K10-1 Commercial 993V Sn-Pb SY88993VKG K10-1 Commercial 993V with Pb-Free bar-line indicator Pb-Free NiPdAu SY88993VKGTR(1) K10-1 Commercial 993V with Pb-Free bar-line indicator Pb-Free NiPdAu 10 VCC DIN 2 9 DOUT MSOP K10-1 /DIN 3 8 /DOUT VREF 4 7 LOS LOSLVL 5 6 GND 10-Pin MSOP (K10-1) Note: 1. Tape and Reel. PIN NAMES Pin GENERAL DESCRIPTION Type General The SY88993V is an integrated limiting amplifier intended for high-frequency fiber-optic applications. The circuit connects to typical transimpedance amplifiers found within a fiber-optics link. The linear signal output from a transimpedance amplifier can contain significant amounts of noise, and may vary in amplitude over time. The SY88993V limiting amplifier quantizes the signal and outputs a voltage-limited waveform. The /EN pin allows the user to disable the output signal without removing the input signal. Function DIN Data Input Data Input /DIN Data Input Inverting Data Input LOSLVL Input Loss of Signal Level Set /EN TTL Input Output Enable (Active Low) LOS TTL Output (Open Collector) Loss of Signal Indicator (Active High) GND Ground Ground DOUT CML Output Data Output /DOUT CML Output Inverting Data Output VCC Power Supply Positive Power Supply VREF Output Reference Voltage Output for LOS Level Set (see Fig. 3) M9999-082205 [email protected] or (408) 955-1690 2 Micrel, Inc. SY88993V ABSOLUTE MAXIMUM RATINGS(1) Symbol Rating Value Unit VCC Power Supply Voltage 0 to +7.0 V DIN, /DIN Input Voltage 0 to VCC V TA Operating Temperature Range –40 to +85 °C Tstore Storage Temperature Range –55 to +125 °C Note: 1. Permanent device damage may occur if absolute maximum ratings are exceeded. This is a stress rating only and functional operation is not implied at conditions other than those detailed in the operational sections of this data sheet. Exposure to absolute maximum ratlng conditions for extended periods may affect device reliability. DC ELECTRICAL CHARACTERISTICS VCC = +3.3V ±10% or +5V ±10%, RLOAD = 50Ω to VCC TA = –40°C Symbol Parameter 5V 3.3V TA = 0°C TA = +25°C TA = +85°C Min. Max. Min. Max. Min. Typ. Max. Min. Max. Unit — — 40 35 — — 40 35 — — 34 30 40 35 — — 45 40 mA ICC Power Supply Current(1) IIL /EN Input LOW Current –0.3(6) — –0.3(6) — –0.3(6) — — –0.3(6) — mA IIH /EN Input HIGH Current — — 20(4) 100(5) — — 20(4) 100(5) — — — — 20(4) 100(5) — — 20(4) 100(5) µA IOH LOS Output Leakage(2) — 100 — 100 — — 100 — 100 uA LOSLVL LOSLVL Level VREF VCC VREF VCC VREF — VCC VREF VCC V VOL LOS Output Low Level(3) — 0.5 — 0.5 — — 0.5 — 0.5 V VREF Reference Voltage VIH /EN Input HIGH Voltage 2.0 — 2.0 — 2.0 — — 2.0 — V VIL /EN Input LOW Voltage — — 0.8 — 0.8 — — 0.8 — V — ±80 — ±80 — ±10 ±80 — ±80 mV VCC–0.2 GND±2 — VCC–0.2 VCC –1.38 VCC –1.26 VCC –1.38 VCC –1.26 VCC –1.38 VCC –1.32 VCC –1.26 VCC –1.38 VCC –1.26 VOFFSET Differential Output Offset VCMR Common Mode Range GND±2 VCC–0.2 GND±2 Notes: 1. No output load. 2. VOH = 5.5V. 3. IOL = +2mA. 4. VIN = 2.7V 5. VIN = VCC 6. VIN = 0.5V M9999-082205 [email protected] or (408) 955-1690 3 GND±2 VCC–0.2 V V Micrel, Inc. SY88993V AC ELECTRICAL CHARACTERISTICS VCC = +3.3V ±10% or +5V ±10%, RLOAD = 50Ω to VCC TA = –40°C Symbol Parameter TA = 0°C TA = +25°C TA = +85°C Min. Max. Min. Max. Min. Typ. Max. Min. Max. Unit HYS LOS Hysteresis 2 8 2 8 2 5.6 8 2 8 dB PSRR Power Supply(1) Rejection Ratio — — — — — 35 — — — dB tOFFL LOS Release Time(2) Minimum Input — 0.5 — 0.5 — 0.1 0.5 — 0.5 µs tOFFH LOS Release Time(3) Maximum Input — 0.5 — 0.5 — 0.1 0.5 — 0.5 µs tONL LOS Assert Time(2) — 0.5 — 0.5 — 0.2 0.5 — 0.5 µs tr tf Output(3) Differential Rise/Fall Time — 120 — 120 — 70 120 — 120 ps VID Input Voltage Range 4 1800 4 1800 4 — 1800 4 1800 mVPP — — — mVPP VOD Differential Output Voltage Swing(4) — — — — — 400(5) VSR LOS Sensitivity Range 4 50 4 50 4 — 50 4 50 mVPP VCC –20 VCC VCC –20 VCC VCC –20 VCC –5 VCC VCC –20 VCC mV Output Spec (DOUT and /DOUT) VOH Output HIGH Voltage VOL Output LOW Voltage(6) VCC –280 VCC –140 VCC –280 VCC –140 VCC –280 ZO Single-Ended Output(7) Impedance VCC –200 VCC –140 VCC –280 VCC –140 mV 40 60 40 60 40 50 60 40 60 Ω Input Spec (DIN and /DIN) AV(Diff) Differential Voltage Gain — — — — — 38 — — — dB B–3dB 3dB Bandwidth — — — — — 2.5 — — — GHz S21 Single-Ended Small Signal-Gain 26 — 26 — 26 32 — 26 — dB Notes: 1. Input referred noise = RMS output noise/low frequency gain. Input referred, 55MHz. 2. Input is a 200MHz square wave, tr < 300ps, 1.8VPP. 3. With input signal VID > 5mVPP. 4. Input is a 200MHz square wave, tr < 300ps, 50Ω load. 5. VID > 5mVPP. 6. Output levels are based on 50Ω impedance. If the load impedance is different, the output level will be changed. 7. See output structure. M9999-082205 [email protected] or (408) 955-1690 4 Micrel, Inc. SY88993V APPLICATION NOTE Output Termination The SY88993V outputs must be terminated with a 50Ω load to VCC. 50Ω 50Ω Layout and PCB Design Since the SY88993V is a high-frequency component, performance can largely be determined by board layout and design. A common problem with high-gain amplifiers is feedback from the large swing outputs to the input via power supply. The SY88993V ground pin should be connected to the circuit board ground. Use multiple PCB vias close to the part to connect to ground. Avoid long, inductive runs which can degrade performance. ESD STRUCTURE VCC VCC DOUT 50Ω Z0 = 50Ω /DOUT Z0 = 50Ω 8mA VCC GND ESD STRUCTURE Figure 2. Differential Output Configuration 22nF DIN VCC /DIN 50Ω 50Ω 22nF R1 LOSLVL R2 VREF 0.1µF GND VREF Figure 1. Differential Input Configuration NOTES: 1. Resistor Divider = R2/ (R1 + R2) 2. R1 + R2 ≥ 5kΩ Figure 3. LOSLVL Circuit M9999-082205 [email protected] or (408) 955-1690 5 50Ω Micrel, Inc. SY88993V PERFORMANCE CURVE LOS Assert and Deassert Levels vs LOSLVL 100 90 3.3V TA = 25°C 2.5Gbps Pattern 223-1 80 70 60 50 INPUT LEVEL (mVp-p) INPUT LEVEL (mVp-p) 100 90 LOS Assert and Deassert Levels vs LOSLVL 40 30 20 10 0 0 60 50 40 30 20 10 0 -0.2 -0.4 -0.6 -0.8 -1.0 -1.2 LOSLVL = VCC – V (V) 5.0V TA = 25°C 2.5Gbps Pattern 223-1 80 70 0 Figure 4. Figure 5. LOS Assert and Deassert Levels vs LOSLVL LOS Assert and Deassert Levels vs LOSLVL 100 90 3.3V TA = 25°C 2.5Gbps Pattern 27-1 70 60 INPUT LEVEL (mVp-p) INPUT LEVEL (mVp-p) 100 90 80 50 40 30 20 10 0 0 Figure 6. 5.0V TA = 25°C 2.5Gbps Pattern 27-1 80 70 60 50 40 30 20 10 0 -0.2 -0.4 -0.6 -0.8 -1.0 -1.2 LOSLVL = VCC – V (V) M9999-082205 [email protected] or (408) 955-1690 -0.2 -0.4 -0.6 -0.8 -1.0 -1.2 LOSLVL = VCC – V (V) 0 -0.2 -0.4 -0.6 -0.8 -1.0 -1.2 LOSLVL = VCC – V (V) Figure 7. 6 SY88993V Micrel, Inc. APPLICATION EXAMPLE FOR 3-CHIP SET SOLUTION GBIC Terminal TX_DATA+ TX_DATA– TX_FAULT TX_DISABLE VCC VCC 200Ω 68Ω DIN /DIN LOSOUT /EN VCC VREF IPIN SET RSER IBIAS SET 20kΩ 0.1µF DIN /DIN 0.1µF IBIAS Laserdiode IBIAS FB VCC 2MΩ 0.1µF 1000pF VCC Laser Module MD RWIN VCCDET 22nF 22nF From Transimpedance Amp. 0.1µF Photodiode VCC OUT /OUT 20kΩ VCC 20KΩ 20kΩ ILIMIT SET SY88904 RSET SY88922 GND 0.1µF VREF 20kΩ VCC VREF SY88993V /EN GND TX_OUT TX_FAULT TX_DISABLE LOSIN LOS DOUT /DOUT LOSLVL VCC 50Ω 68Ω 50Ω 7 M9999-082205 [email protected] or (408) 955-1690 RX_LOS RX_DATA+ RX_DATA– GND 0.1µF 50Ω 200Ω 50Ω Micrel, Inc. SY88993V 10 LEAD MSOP (K10-1) Rev. 00 MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 TEL + 1 (408) 944-0800 FAX + 1 (408) 474-1000 WEB USA http://www.micrel.com The information furnished by Micrel in this datasheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is at Purchaser’s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. © 2005 Micrel, Incorporated. M9999-082205 [email protected] or (408) 955-1690 8