5V/3.3V 3.2Gbps HIGH-SPEED LIMITING POST AMPLIFIER Micrel, Inc. DESCRIPTION FEATURES ■ ■ ■ ■ ■ ■ ■ Single 3.3V or 5V power supply Up to 3.2Gbps operation Low noise PECL data outputs Chatter-free open collector TTL LOS output TTL /EN Input Differential PECL inputs for data Available in a tiny 10-pin (3mm) MSOP and 10-pin (3mm) EPAD-MSOP The SY88923AV limiting post amplifier with its high gain and wide bandwidth is ideal for use as a post amplifier in fiber-optic receivers with data rates up to 3.2Gbps. Signals as small as 5mVPP can be amplified to drive devices with PECL inputs. The SY88923AV generates a chatter-free Loss-of-Signal (LOS) open collector TTL output. The SY88923AV incorporates a programmable level detect function to identify when the input signal has been lost. The LOS output will change from logic “LOW” to logic “HIGH” when input signal is smaller than the swing set by LOSLVL. This information can be fed back to the EN input of the device to maintain stability under loss-of-signal condition. Using LOSLVL pin, the sensitivity of the level detection can be adjusted. The LOSLVL voltage can be set by connecting a resistor divider between VCC and VREF shown in Figure 3. “Typical Operating Characteristics” on page 6 show the relationship between input level sensitivity and the voltage set on LOSLVL. The LOS output is a TTL open collector output that requires a pull-up resistor for proper operation, Figure 1. APPLICATIONS ■ ■ ■ ■ ■ ■ ■ SY88923AV SY88923AV 1.25Gbps and 2.5Gbps Gigabit Ethernet 531Mbps, 1062Mbps and 2.12Gbps Fibre Channel 622Mbps SONET Gigabit interface converter 2.5Gbps SDH/SONET 2.5Gbps proprietary links Parallel 10G Ethernet VCC SY88923AV LOS 4.7kΩ to 10kΩ Figure 1. LOS Output with Desired Rise Time BLOCK DIAGRAM DIN DOUT Limiting Amplifer ECL Buffer /DIN /DOUT VREF Enable /EN VCC GND Level Detect LOS LOSLVL M9999-110905 [email protected] or (408) 955-1690 Rev.: F 1 Amendment: /0 Issue Date: November 2005 Micrel, Inc. SY88923AV PACKAGE/ORDERING INFORMATION Ordering Information(1) /EN 1 10 VCC DIN 2 9 DOUT /DIN 3 8 /DOUT VREF 4 7 LOST LOSLVL 5 Package Type Operating Range Package Marking Lead Finish SY88923AVKC K10-1 Commercial 923AV Sn-Pb SY88923AVKCTR(2) K10-1 Commercial 923AV Sn-Pb SY88923AVEC K10-2 Commercial 923AV Sn-Pb SY88923AVECTR(2) K10-2 Commercial 923AV Sn-Pb SY88923AVKG(3) K10-1 Industrial 923AV with Pb-free bar-line indicator NiPdAu Pb-Free SY88923AVKGTR(2, 3) K10-1 Industrial 923AV with Pb-free bar-line indicator NiPdAu Pb-Free SY88923AVEY(3) K10-2 Industrial 923AV with Matte-Sn Pb-free bar-line indicator Pb-Free SY88923AVEYTR(2, 3) K10-2 Industrial 923AV with Matte-Sn Pb-free bar-line indicator Pb-Free Part Number 6 GND 10-Pin MSOP (K10-1) 10-Pin EPAD-MSOP (K10-2) Notes: 1. Contact factory for die availability. Dice are guaranteed at TA = 25°C, DC Electricals only. 2. Tape and Reel. 3. Pb-Free package is recommended for new designs. PIN DESCRIPTION Pin Number MSOP Pin Number EPAD-MSOP Pin Name Type 1 1 /EN TTL Input Output Enable (Active Low). 2 2 DIN Data Input Data Input. 3 3 /DIN Data Input Inverting Data Input. 4 4 VREF Output 5 5 LOSLVL Input 6 6, (Exposed Pad) GND Ground 7 7 LOS TTL Output (Open Collector) 8 8 /DOUT PECL Output Inverting Data Output. 9 9 DOUT PECL Output Data Output. 10 10 VCC Power Supply Positive Power Supply. M9999-110905 [email protected] or (408) 955-1690 Pin Function Reference Voltage Output for LOS Level Set (see Figure 3). LOS Limit Set. Ground. Exposed pad must be connected to PCB ground plane. 2 Loss of Signal Indicator (Active High). Micrel, Inc. SY88923AV Absolute Maximum Ratings(1) Operating Ratings(2) Power Supply Voltage (VCC) ............................ 0V to +7.0V Input Voltage (DIN, /DIN) ........................................................ 0V to VCC (/EN) ................................................................ 0V to VCC (LOSLVL) .......................................................... 0V to VCC Output Voltage (with 50Ω load) (DOUT, /DOUT) .......................... VCC –2.5V to VCC +0.3V (VREF) .................................................. VCC –2.0V to VCC Lead Temperature (soldering, 20 sec.) ..................... 260°C Storage Temperature (TS) ....................... –55°C to +125°C Supply Voltage (VCC) .................................. +3.0V to +5.5V Ambient Temperature (TA) ......................... –40°C to +85°C Package Thermal Resistance MSOP (θJA) Still-Air ........................................................... 113°C/W EPAD-MSOP (θJA) Still-Air ............................................................. 38°C/W DC ELECTRICAL CHARACTERISTICS(3) VCC =+5V ±10% or +3.3V ±10%; RL = 50Ω to VCC –2V; TA = –40°C to +85°C; unless otherwise noted. Symbol Parameter Condition Min ICC Power Supply Current No output load VCC = 5V ±10%, VCC = 3.3V ±10% Typ Max Units 38 35 60 53 mA mA IIL /EN Input LOW Current VIN = 0.5V IIH /EN Input HIGH Current VIN = 2.7V VIN = VCC VCMR Common Mode Range Voffset Differential Output Offset LOSLVL LOSLVL Level VOL LOS Output LOW Level IOH LOS Output Leakage VOH DOUT and /DOUT Output HIGH Voltage VCC –1085 VCC –955 VCC –880 mV DOUT and /DOUT Output LOW Voltage VCC –1830 VCC –1705 VCC –1555 mV VREF Reference Supply VCC –1.38 VCC –1.32 VCC –1.26 V IREF VREF Output Current –0.8 VIH /EN Input HIGH Voltage 2.0 VIL /EN Input LOW Voltage VOL –0.3 mA 20 100 µA µA VCC V ±80 mV VCC V IOL = +2mA 0.5 V VOH = 5.5V 100 µA GND +2.0 VREF 0.5 mA V 0.8 V Notes: 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. 2. The data sheet limits are not guaranteed if the device is operated beyond the operating ratings. 3. The device is guaranteed to meet the DC specifications, shown in the table above, after thermal equilibrium has been established. The device is tested in a socket such that transverse airflow of ≥500lfpm is maintained. M9999-110905 [email protected] or (408) 955-1690 3 Micrel, Inc. SY88923AV AC ELECTRICAL CHARACTERISTICS VCC =+5V ±10% or +3.3V ±10%; RL = 50Ω to VCC –2V; TA = –40°C to +85°C; unless otherwise noted. Symbol Parameter VID Input Voltage Range VOD Differential Output Voltage Swing Condition Min Typ 5 Note 4 VID = 15mVPP VID = 5mVPP Max Units 1800 mVPP 1400 600 mVPP mVPP tON LOS Assert Time Note 5 0.2 0.5 µs tOFF LOS Release Time Note 5 0.1 0.5 µs VSR LOS Sensitivity Range 223–1 pattern 5 50 mVPP HYS LOS Hysteresis 223–1 pattern 2 4.6 8 dB tr, tf Output Rise/Fall Time VID > 100mVPP VID < 100mVPP 115 trin,tfin 150 ps Notes: 4. Input is a 200MHz square wave, tr < 300ps. 5. Input is a 200MHz square wave, tr < 300ps, 1.8VPP. M9999-110905 [email protected] or (408) 955-1690 4 Micrel, Inc. SY88923AV GENERAL DESCRIPTION General The SY88923AV is an integrated limiting amplifier intended for high-frequency fiber-optic applications. The circuit connects to typical trans-impedance amplifiers found within a fiber-optics link. The linear signal output from a trans-impedance amplifier can contain significant amounts of noise, and may vary in amplitude over time. The SY88923AV 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. DESIGN PROCEDURE Output Termination The SY88923AV outputs must be terminated with a 50Ω load to VCC – 2V (or Thevenin equivalent). The SY88923AV 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. Layout and PCB Design Since the SY88923AV 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 the power supply. VCC R1 LOSLVL R2 0.1µF DIN+ VREF 0.1µF DIN— 50Ω VCC 50Ω VREF Figure 3. LOSLVL Circuit Note 1. 0.1µF R1 + R2 ≥ 2.6kΩ Figure 2. Differential Input Configuration M9999-110905 [email protected] or (408) 955-1690 LOSLVL = VCC –1.32V + 5 R2 × 1.32V R1 + R2 Micrel, Inc. SY88923AV TYPICAL OPERATING CHARACTERISTICS INPUT LEVEL (mVpp) 80 70 60 50 De-Assert 40 30 20 10 0 100 INPUT LEVEL (mVpp) 100 3.3V TA = 25¡C 2.5Gbps Pattern 223-1 Assert 0 -0.2 -0.4 -0.6 -0.8 -1.0 -1.2 LOSLVL = VCC — V (V) LOS Assert and De-Assert Levels vs. LOSLVL 50 40 30 20 10 0 De-Assert Assert -0.2 -0.4 -0.6 -0.8 -1.0 -1.2 LOSLVL = VCC — V (V) M9999-110905 [email protected] or (408) 955-1690 6 5.0V TA = 25¡C 2.5Gbps Pattern 223-1 50 40 30 20 10 0 De-Assert Assert 0 -0.2 -0.4 -0.6 -0.8 -1.0 -1.2 LOSLVL = VCC — V (V) LOS Assert and De-Assert Levels vs. LOSLVL 5.0V TA = 25¡C 2.5Gbps Pattern 27-1 80 70 60 50 De-Assert 40 30 20 10 0 0 LOS Assert and De-Assert Levels vs. LOSLVL 90 80 70 60 100 90 3.3V TA = 25¡C 2.5Gbps Pattern 27-1 90 80 70 60 INPUT LEVEL (mVpp) INPUT LEVEL (mVpp) 100 90 LOS Assert and De-Assert Levels vs. LOSLVL Assert 0 -0.2 -0.4 -0.6 -0.8 -1.0 -1.2 LOSLVL = VCC — V (V) Micrel, Inc. SY88923AV 10-PIN MSOP (K10-1) Rev. 00 M9999-110905 [email protected] or (408) 955-1690 7 Micrel, Inc. SY88923AV 10-PIN EPAD-MSOP (K10-2) +0.08 -0.08 +0.003 -0.003 +0.05 -0.05 +0.002 -0.002 +0.15 -0.15 +0.004 -0.004 +0.10 -0.10 +0.004 -0.004 +0.008 -0.008 +0.003 -0.003 +0.07 -0.08 +0.003 -0.003 Rev.01 +0.15 -0.15 +0.006 -0.006 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. M9999-110905 [email protected] or (408) 955-1690 8