SY55854U 2 x 2 Protection Crosspoint Switch General Description The SY55854U is a fully differential, CML, 2 x 2-crosspoint switch. The non-blocking design allows any input to be connected to any output. Varying the state of the select inputs allows SY55854U to be used in backup, fault tolerant, protection, and backplane distribution applications. SY55854U inputs can be terminated with a single resistor between the true and the complement pins of a given input. The SY55854U is a member of Micrel’s new SuperLite® family of high-speed logic devices. This family features very small packaging, high signal integrity, and flexible supply voltage operation. Datasheets and support documentation can be found on Micrel’s web site at: www.micrel.com. Functional Block Diagram SuperLite® Features • Guaranteed fMAX >2.5GHz over temperature • • • • • • • • • • 2.3V to 5.7V power supply Non-blocking “switch architecture” Guaranteed <15ps channel-to-channel skew Guaranteed <480ps propagation delay over temperature Configurable as 2:1 mux, 1:2 fan-out buffer, dual buffer, or 2 x 2 switch Accepts CML, PECL, LVPECL inputs Fully differential inputs/outputs Source terminated CML outputs for fast edge rates Wide operating temperature range: –40°C to +85°C Available in a tiny 16-pin EPAD-QSOP package Applications • • • • • High-speed logic Data communications systems Wireless communications systems Telecom systems Backplane redundancy SuperLite is a registered trademark of Micrel, Inc. Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com January 2010 M9999-011210-G [email protected] or (408) 955-1690 Micrel, Inc. SY55854U Ordering Information(1) Part Number Package Type Temperature Range Package Lead Finish SY55854UYI Y16-1 Industrial 854U Sn-Pb SY55854UYITR(2) Y16-1 Industrial 854U Sn-Pb SY55854UYY(3) Y16-1 Industrial 854U with Pb-Free bar-line indicator Matte-Sn Pb-Free SY55854UYYTR(2, 3) Y16-1 Industrial 854U with Pb-Free bar-line indicator Matte-Sn Pb-Free 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 recommended for new designs. Pin Configuration 16-Pin EPAD-QSOP (Y16-1) Pin Description Pin Number Pin Name Pin Function 2, 3 D0, /D0 CML/PECL/LVPECL Input (Differential). This is one of the data inputs to the crosspoint. It will be switched either to the Q0 output, the Q1 output, both outputs, or neither output, depending on the state of the S0 and S1 inputs. 4, 5 S0, /S0 CML/PECL/LVPECL Input (Differential). This selects input chooses which data input switches to the Q0 output. S0 logic low selects the D0 input, while S0 logic high selects the B input. 6, 7 /D1, D1 CML/PECL/LVPECL Input (Differential). This is the other data input to the crosspoint. It will be switched either to the Q0 output, the Q1 output, both outputs, or neither output, depending on the state of the S0 and S1 inputs. 1, 8 GND Ground. Power Supply. 9, 16 VCC 10, 11 Q1, /Q1 CML Output (Differential). This is the other output from the crosspoint. Input S1 selects either the D0 or D1 input to be switched to this output. 12, 13 /S1, S1 CML/PECL/LVPECL Input (Differential). This select input chooses which data input switches to the Q1 output. S1 logic low selects the D0 input, while S1 logic high selects the D1 input. 14, 15 /Q0, Q0 CML Output (Differential). This is one output from the crosspoint. Input S0 selects either the D0 or the D1 input to be switched to this output. January 2010 2 M9999-011210-G [email protected] or (408) 955-1690 Micrel, Inc. Functional Description Establishing Static Logic Inputs The true pin of an input pair is internally biased to ground through a 75kΩ resistor. The complement pin of an input pair is internally biased halfway between VCC and ground by a voltage divider consisting of two 75kΩ resistors. In this way, unconnected inputs appear as logic zeros. To keep an input at static logic zero at VCC > 3.0V, leave both inputs unconnected. For VCC ≤ 3.0V, connect the complement input to VCC and leave the true input unconnected. To make an input static logic one, connect the true input to VCC, and leave the complement input unconnected. These are the only two safe ways to cause inputs to be at a static value. In particular, no input pin should be directly connected to ground. All NC (no connect) pins should be unconnected. SY55854U Usage SY55854U is very versatile. Tying its select inputs in various ways varies its functionality. For example, tying the select inputs together turns SY55854U into a redundant distributor. Either input will be switched to both outputs simultaneously. This is very useful in redundant backplane applications. By cross-tying the select inputs, SY55854U becomes a true crosspoint, selecting between “straight through” and “cross connected” operation. Also, using the select inputs independently, SY55854U functions as two multiplexers. Setting the select inputs to static values turns SY55854U into a dual buffer, or a fan-out buffer. To make larger crosspoints, cascade SY55854U devices, either in a tree, or in a Banyan structure, as appropriate for your application. Figure 1. Hard Wiring a Logic “1” (1) Note: 1. X is either D0, D1, S0, or S1 input. /X is either /D0, /D1, /S0, or /S1 input. Figure 2. Hard Wiring a Logic “0” (1) January 2010 3 M9999-011210-G [email protected] or (408) 955-1690 Micrel, Inc. SY55854U Truth Table S0 S1 Q0 Q1 Function 0 0 D0 D0 Fan-Out Buffer 0 1 D0 D1 Dual Buffer 1 0 D1 D0 Dual Buffer 1 1 D1 D1 Fan-Out Buffer CTL CTL Same Same Redundant Distribution CTL /CTL Opposite Opposite Crosspoint January 2010 4 M9999-011210-G [email protected] or (408) 955-1690 Micrel, Inc. SY55854U Absolute Maximum Ratings(1) Operating Ratings(2) Supply Voltage (VCC).......................................–0.5 to +6.0V Input Voltage (VIN) ....................................–0.5 to VCC +0.5V CML Output Voltage (VOUT).............. VCC –1.0 to VCC +0.5V Lead Temperature (soldering, 20sec.)....................... 260°C Storage Temperature (Ts) ............................. –65 to +150°C Supply Voltage (VIN)........................................–0.5 to +6.0V Ambient Temperature (TA) .............................. –40 to +85°C DC Electrical Characteristics VCC = 2.3V to 5.7V; GND = 0V; TA = –40°C to +85°C Symbol Parameter Condition VCC Power Supply Voltage ICC Power Supply Current Min Typ 2.3 Max Units 5.7 V 60 mA Max Units CML DC Electrical Characteristics VCC = 2.3V to 5.7V; GND = 0V; TA = –40°C to +85°C(3) Symbol Parameter VID Differential Input Voltage 100 VIH Input HIGH Voltage 1.6 VCC V VIL Input LOW Voltage 1.5 VCC-0.1 V VOH Output HIGH Voltage No Load VCC – 0.020 VCC – 0.010 VCC V VOL Output LOW Voltage No Load VCC – 0.97 VCC – 0.825 VCC – 0.660 V No Load 0.700 0.800 0.950 V VOS Output Voltage Condition Swing(4) 100Ω Min Environment(5) 50Ω Environment(6) RDRIVE Output Source Impedance 80 Typ mV 0.400 V 0.200 V 100 120 Ω 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 rating conditions for extended periods may affect device reliability. 2. The device is not guaranteed to function outside its operating rating. 3. Equilibrium temperature. 4. Actual voltage levels and differential swing will depend on customer termination scheme. Typically, a 400mV swing is available in the 100Ω environment and a 200mV swing in the 50Ω environment. Refer to the “CML Termination” diagram for more details 5. See Figure 4. 6. See Figure 3a and 3b. January 2010 5 M9999-011210-G [email protected] or (408) 955-1690 Micrel, Inc. SY55854U AC Electrical Characteristics(8, 9) VCC = 2.3V to 5.7V; GND = 0V; TA = –40°C to +85°C Symbol Parameter Condition Min Typ Max fMAX Max. Operating Frequency tPD Propagation Delay, S0, S1, D0, D1 to Q0, Q1 400 mA tSKEW Within-Device Skew(9) Part-to-Part Skew (Diff.) 15 100 ps tr, tf CML Output Rise/Fall Times (20% to 80%) 150 ps 2.5 Units V Notes: 8. Tested using environment of Figure 3b, 50Ω load CML output. 9. Worst case difference between Q0 and Q1 from either A or B, when both outputs come from the same input. January 2010 6 M9999-011210-G [email protected] or (408) 955-1690 Micrel, Inc. SY55854U CML Termination All inputs accept the output from any other member of this family. All outputs are source terminated 100Ω CML differential drivers as shown in Figures 3 and 4. SY55854U expects the inputs to be terminated, and that good high speed design practices be adhered to. SY55854U inputs are designed to accept a termination resistor between the true and complement inputs of a differential pair. 0402 form factor chip resistors will fit with some trace fanout. Figure 3b. Individually Terminated (50Ω Load CML Output) Figure 3a. Differentially Terminated (50Ω Load CML Output) Figure 4. 100Ω Load CML Output January 2010 7 M9999-011210-G [email protected] or (408) 955-1690 Micrel, Inc. SY55854U Package Information 16-Pin EPAD-QSOP (Y16-1) 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. © 2006 Micrel, Incorporated. January 2010 8 M9999-011210-G [email protected] or (408) 955-1690