SY84403BL Ultra Small 3.3V 4.25Gbps CML Low-Power Limiting Post Amplifier with TTL LOS General Description Features The SY84403BL is the industry’s smallest limiting post amplifier ideal for compact copper and fiber optic module applications. The device connects to typical transimpedance amplifiers (TIAs). The linear signal output from TIAs can contain significant amounts of noise and may vary in amplitude over time. The SY84403BL quantizes these signals and outputs typically 800mVPP voltage-limited waveforms. ® The SY84403BL comes in a tiny 10-pin 2x2 MLF package, which is unparalleled in the industry. It offers space savings of 55% or more over typical post amps. It operates from a single +3.3V ±10% power supply, over an industrial temperature range of –40°C to +85°C. With its wide bandwidth and high gain, signals with data rates up to 4.25Gbps and as small as 10mVPP can be amplified to drive devices with CML inputs or AC-coupled PECL inputs. The SY84403BL incorporates a loss-of-signal (LOS) open-collector TTL output with internal 4.75kΩ pull-up resistor. A programmable loss-of-signal level set pin (LOSLVL) sets the sensitivity of the input amplitude detection. LOS asserts high if the input amplitude falls below the threshold set by LOSLVL and de-asserts low otherwise. LOS can be fed back to the enable bar (/EN) input to maintain output stability under a loss of signal condition. /EN de-asserts the true output signal without removing the input signal. All support documentation can be found on Micrel’s web site at: www.micrel.com. • Available in an ultra small 10-pin (2mm x 2mm) ® MLF package • Multi-rate up to 4.25Gbps operation • 10mVPP input sensitivity • Low noise 50Ω CML data outputs – 800mVPP differential output swing – 60ps edge rates – 1psRMS typ. random jitter – 10psPP typ. deterministic jitter • Chatter-free Loss-of-Signal (LOS) output – 3.5dB electrical hysteresis – OC-TTL output with internal 4.75kΩ pull-up resistor • Programmable LOS sensitivity using single external resistor • Internal 50Ω data input termination • TTL /EN input allows feedback from LOS • Wide operating range: – Single 3.3V ±10% power supply – Industrial temperature range: –40°C to +85°C • Part of Micrel’s new ultra small FOM IC family. For Laser Diode Drivers, see SY84202L or SY84402L Typical Performance Applications • 1.062Gbps, 2.125Gbps and 4.25Gbps Fibre Channel • Cable driver • SFF and SFP transceivers • High-gain line driver and line receiver Markets • Copper interconnect • Datacom and telecom • Storage area network (SAN) MLF and MicroLeadFrame are registered trademarks of Amkor Technology. Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com May 2009 M9999-051509-A [email protected] or (408) 955-1690 Micrel, Inc. SY84403BL Typical Application Functional Block Diagram May 2009 2 M9999-051509-A [email protected] or (408) 955-1690 Micrel, Inc. SY84403BL Ordering Information(1) Part Number SY84403BLMGTR Package Type Operating Range Package Marking Lead Finish MLF-10 Industrial 403 with Pb-Free bar-line indicator NiPdAu Pb-Free Notes: 1. Contact factory for die availability. Dice are guaranteed at TA = 25°C, DC Electricals only. Pin Configuration ® 10-Pin MLF (MLF-10) Pin Description Pin Number Pin Name Type 1, 2 DIN, /DIN Differential Data Input 3 VREF 4 LOSLVL Input: Default is Maximum Sensitivity Loss-of-Signal level set: A resistor from this pin to VCC sets the threshold for the data input amplitude at which the LOS output will be asserted. 5 GND Exposed Pad Ground Device ground. Exposed pad must be soldered (or equivalent) to the same potential as the ground pin. 6 LOS TTL Output Loss-of-Signal: Asserts high when the data input amplitude falls below the threshold set by LOSLVL. Contains Internal 4.75kΩ pull-up resistor 8, 7 DOUT, /DOUT Differential CML Output Differential data output. 9 VCC Power Supply 10 /EN TTL Input: Default is high May 2009 Pin Function Differential data input. Each pin internally terminates to REF through 50Ω. Reference Voltage. Bypass with 0.01µF low ESR capacitor from VREF to VCC to stabilize LOSLVL and VREF. Positive power supply. Bypass with 0.1µF||0.01µF low ESR capacitors. 0.01µF capacitors should be as close as possible to VCC pin. Enable bar: De-asserts true data output when high. Incorporates 25kΩ pull-up to VCC. 3 M9999-051509-A [email protected] or (408) 955-1690 Micrel, Inc. SY84403BL Absolute Maximum Ratings(1) Operating Ratings(2) Supply Voltage (VCC) .....................................0V to 4.0V /EN, LOSLVL Voltage........................................ 0 to VCC REF Current ......................................................... ±1mA LOS Current ......................................................... ±5mA DOUT, /DOUT Current ....................................... ±25mA DIN, /DIN Current ............................................... ±10mA Lead Temperature (soldering, 20sec.) ................ 260°C Storage Temperature (Ts) .................. –65°C to +150°C Supply Voltage (VCC).............................. +3.0V to +3.6V Ambient Temperature (TA) ....................–40°C to +85°C Junction Temperature (TA) ..................–40°C to +125°C (3) Package Thermal Resistance ® MLF θJA (Still-Air) ............................................ 93°C/W ψJB .......................................................... 56°C/W DC Electrical Characteristics VCC = +3.0V to +3.6V; TA = –40°C to +85°C; typical values at VCC = +3.3V, TA = 25°C. Symbol Parameter Condition Typ Max Units ICC Power Supply Current Note 4 Min 25 42 mA Note 5 41 62 mA VREF REF Voltage VCC –1.3 VLOSLVL LOSLVL Voltage Range VCC V VOH DOUT, /DOUT HIGH Voltage Note 6 VCC –0.020 VCC –0.005 VCC V VOL DOUT, /DOUT LOW Voltage VCC = 3.3V, Note 6 VCC –0.475 VCC –0.400 VCC –0.350 V VOFFSET Differential Output Offset ±80 mV ZO Single-Ended Output Impedance 40 50 60 Ω ZI Single-Ended Input Impedance 40 50 60 Ω Typ Max Units VCC V 0.5 V VREF V TTL DC Electrical Characteristics VCC = +3.0V to +3.6V; TA = –40°C to +85°C. Symbol Parameter Condition Min VOH LOS Output HIGH Level Sourcing 100µA 2.4 VOL LOS Output LOW Level Sinking 2mA VIH /EN Input HIGH Voltage VIL /EN Input LOW Voltage IIH /EN Input HIGH Current VIN = 2.7V VIN = VCC IIL /EN Input LOW Current VIN = 0.5V 2.0 –0.3 V 0.8 V 20 100 µA µA mA Notes: 1. Permanent device damage may occur if ratings in the absolute maximum ratings section are exceeded. This is a stress rating only and functional operation is not implied for conditions other than those detailed in the operational sections of this data sheet. Exposure to absolute maximum ratings 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. Thermal performance assumes are of 4-layer PCB. Exposed pad must be soldered (or equivalent) to the device's most negative potential on the PCB. 4. Excludes current of CML output stage. See “Detailed Description.” 5. Total device current with no output load. 6. If the load impedance is different, the output level will be changed. Amplifier is in limiting mode. May 2009 4 M9999-051509-A [email protected] or (408) 955-1690 Micrel, Inc. SY84403BL AC Electrical Characteristics VCC = +3.0V to +3.6V; TA = –40°C to +85°C; RL = 50 Ω to VCC; typical values at VCC = +3.3V, TA = 25°C. Symbol Parameter Condition tr, tf Output Rise/Fall Time (20% to 80%) tJITTER Deterministic Random Min Typ Max Units Note 7 60 120 ps Note 8 Note 9 10 1 VID Differential Input Voltage Swing See Figure 1 10 VOD_AC AC Differential Output Voltage Note 10 600 tOFF LOS Release Time tON LOS Assert Time psPP psRMS 1800 mVpp 800 950 mVpp 2 10 µs 2 10 µs LOSAL Low LOS Assert Level RLOSLVL = 15kΩ, Note 11 LOSDL Low LOS De-assert Level RLOSLVL = 15kΩ, Note 11 HSYL Low LOS Hysteresis RLOSLVL = 15kΩ, Note 12 2 LOSAM Medium LOS Assert Level RLOSLVL = 5kΩ, Note 11 12 LOSDM Medium LOS De-assert Level RLOSLVL = 5kΩ, Note 11 HSYM Medium LOS Hysteresis RLOSLVL = 5kΩ, Note 12 LOSAH High LOS Assert Level RLOSLVL = 100Ω, Note 11 LOSDH High LOS De-assert Level RLOSLVL = 100Ω, Note 11 HSYH High LOS Hysteresis RLOSLVL = 100Ω, Note 12 VSR LOS Sensitivity Range 10 AV(Diff) Differential Voltage Gain 32 38 dB S21 Single-Ended Small-Signal Gain 26 32 dB 8 mVPP 12 mVPP 3.5 4.5 17 dB mVPP 25 33 mVPP 2 3.5 4.5 dB 34 47 70 83 mVPP 2 3.5 4.5 dB 35 mVPP mVPP Notes: 7. Amplifier in limiting mode. Input is a 200MHz square wave. 8. Deterministic jitter measured using 4.25Gbps K28.5 pattern, VID = 20mVPP. 9. Random jitter measured using 4.25Gbps K28.7 pattern, VID = 20mVPP. 10. Differential output swing measured at 4.25Gbps with 20mVpp input and PRBS-23 data pattern and 50Ω load. 11. See “Typical Operating Characteristics” for a graph showing how to choose a particular RLOSLVL for a particular LOS assert and its associated de-assert amplitude. 12. This specification defines electrical hysteresis as 20log(LOS De-assert/LOS Assert). The ratio between optical hysteresis and electrical hysteresis is found to vary between 1.5 and 2 depending on the level of received optical power and ROSA characteristics. Based on that ratio, the optical hysteresis corresponding to the electrical hysteresis range 2dB-4.5 dB shown in the AC characteristics table will be 0.5dB3dB Optical Hysteresis. May 2009 5 M9999-051509-A [email protected] or (408) 955-1690 Micrel, Inc. SY84403BL Typical Operating Characteristics 60 Power Supply Current vs. Temperature 55 50 45 40 35 30 25 -40 RLOSLVL (kΩ) RLOSLVL (kΩ) Differential Output Voltage Swing vs. Temperature (Amplifier in Limiting Mode) 900 880 860 840 820 800 780 760 740 720 700 -40 May 2009 -15 10 35 60 TEMPERATURE (°C) 85 Differential Output Voltage Swing vs. Differential Input Voltage Swing 900 800 700 600 500 400 300 200 100 0 -15 10 35 60 TEMPERATURE (°C) 85 0 5 10 15 20 25 30 35 40 45 50 VID (mVpp) 6 M9999-051509-A [email protected] or (408) 955-1690 Micrel, Inc. SY84403BL Detailed Description Loss-of-Signal The SY84403BL incorporates a chatter-free loss-ofsignal (LOS) open-collector TTL output with internal 4.75kΩ pull-up resistor as shown in Figure 5. LOS is used to determine that the input amplitude is too small to be considered a valid input. LOS asserts high if the input amplitude falls below the threshold set by LOSLVL and de-asserts low otherwise. LOS can be fed back to the enable (/EN) input to maintain output stability under a loss of signal condition. /EN deasserts low the true output signal without removing the input signals. Typically, 3.5dB LOS hysteresis is provided to prevent chattering. The SY84403BL low-power limiting post amplifier operates from a single +3.3V power supply, over temperatures from –40°C to +85°C. Signals with data rates up to 4.25Gbps and as small as 10mVPP can be amplified. Figure 1 shows the allowed input voltage swing. The SY84403BL generates an LOS output, allowing feedback to /EN for output stability. LOSLVL sets the sensitivity of the input amplitude detection. SY84403BL is available in the industry’s smallest form ® factor, a tiny 10-pin (2mm x 2mm) MLF package. It is part of Micrel’s new family of ultra-small Fiber Optic ICs. Input Amplifier/Buffer The SY84403BL’s inputs are internally terminated with 50Ω-to-REF. If not affected by this internal termination scheme, upstream devices need to be AC-coupled to the SY84403BL's inputs. Figure 2 shows a simplified schematic of the input stage. The high-sensitivity of the input amplifier allows signals as small as 10mVPP to be detected and amplified. The input amplifier allows input signals as large as 1800mVPP. Input signals are linearly amplified with a typically 38dB differential voltage gain. Since it is a limiting amplifier, the SY84403BL outputs typically 800mVPP voltage-limited waveforms for input signals that are greater than 20mVPP. Applications requiring the SY84403BL to operate with high-gain should have the upstream TIA placed as close as possible to the SY84403BL’s input pins to ensure the best performance of the device. Loss-of-Signal Level Set A programmable loss-of-signal level set pin (LOSLVL) sets the threshold of the input amplitude detection. Connecting an external resistor between VCC and LOSLVL sets the voltage at LOSLVL. This voltage ranges from VCC to VREF. The external resistor creates a voltage divider between VCC and VREF as shown in Figure 6. If desired, an appropriate external voltage may be applied rather than using a resistor. The relationship between VLOSLVL and RLOSLVL is given by: RLOSLVL VLOSLVL = VCC − 1.3 RLOSLVL + 2.8 where voltages are in volts and resistances are in kΩ. The smaller the external resistor, implying a smaller voltage difference from LOSLVL to VCC, lowers the LOS sensitivity. Hence, larger input amplitude is required to de-assert LOS. “Typical Operating Characteristics” contains graphs showing the relationship between the input amplitude detection sensitivity and RLOSLVL. Output Buffer The SY84403BL’s CML output buffer is designed to drive 50Ω lines. The output buffer requires appropriate termination for proper operation. An external Ω 50 resistor to VCC or equivalent for each output pin provides this. Figure 3 shows a simplified schematic of the output stage and includes an appropriate termination method. Of course, driving a downstream device with a CML input that is internally terminated with 50 Ω -to-VCC eliminates the need for external termination. As noted in the previous section, the amplifier outputs typically 800mVPP waveforms across 25Ω total loads. The output buffer thus switches typically 16mA tail-current. Figure 4 shows the power supply current measurement, which excludes the 16mA tail-current. May 2009 Hysteresis The SY84403BL typically provides 3.5dB LOS electrical hysteresis. By definition, a power ratio measured in dB is 10log (power ratio). Power is 2 calculated as VIN /R for an electrical signal. Hence, the same ratio can be stated as 20log (voltage ratio). While in linear mode, the electrical voltage input changes linearly with the optical power and hence the ratios change linearly. Therefore, the optical hysteresis in dB is half the electrical hysteresis in dB given in the datasheet. The SY84403BL provides typically 1.75dB LOS optical hysteresis. As the SY84403BL is an electrical device, this datasheet refers to hysteresis in electrical terms. With 3.5dB LOS hysteresis, a voltage factor of 1.5 is required to de-assert LOS. 7 M9999-051509-A [email protected] or (408) 955-1690 Micrel, Inc. SY84403BL Figure 1. VIS and VID Definition Figure 2. Input Structure May 2009 Figure 3. Output Structure 8 M9999-051509-A [email protected] or (408) 955-1690 Micrel, Inc. SY84403BL Figure 5. LOS Output Structure Figure 6. LOSLVL Setting Circuit Figure 4. Power Supply Current Measurement Related Product and Support Documentation Part Number Function Datasheet Link Application Notes Notes on Sensitivity and Hysteresis in Micrel Post Amplifier www.micrel.com/product-info/app_hints+notes.shtml May 2009 9 M9999-051509-A [email protected] or (408) 955-1690 Micrel, Inc. SY84403BL Package Information ® 10-Pin MicroLeadFrame (MLF-10) MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com The information furnished by Micrel in this data sheet 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 a Purchaser’s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. © 2009 Micrel, Incorporated. May 2009 10 M9999-051509-A [email protected] or (408) 955-1690