Preliminary Revised August 2001 FSTU162450 Configurable 4-Bit to 20-Bit Bus Switch with −2V Undershoot Protection and 25Ω Series Resistors in Outputs (Preliminary) General Description Features The Fairchild Universal Bus Switch FSTU162450 provides 4-bit, 5-bit, 8-bit, 10-bit, 16-bit, 20-bit of high-speed CMOS TTL-compatible bus switching. The low On Resistance of the switch allows inputs to be connected to outputs without adding propagation delay or generating additional ground bounce noise. ■ Undershoot protected to −2V (A and B Ports) The FSTU162450 is designed to allow “customer” configuration control of the enable connections. The device can be organized as either a five 4-bit, four 5-bit, two 10-bit or one 20-bit enable bus switch. Also achieveable are 8-bit and 16-bit enabled configurations (see Functional Description). The device’s bit configuration is controlled through select pin logic. (see Truth Table). When OEx is LOW, Port Ax is connected to Port Bx. When OEx is HIGH, the switch is OPEN. ■ Control inputs compatible with TTL level The A and B Ports are protected against undershoot to support an extended range to 2.0V below ground. Fairchild’s integrated Undershoot Hardened Circuit (UHC) senses undershoot at the I/O and responds by preventing voltage differentials from developing and turning the switch on. ■ 25Ω switch connection between two ports ■ Minimal propagation delay through the switch ■ Low lCC ■ Zero bounce in flow-through mode ■ See Applications Notes AN-5008 and AN-5021 for UHC details ■ Also packaged in plastic Fine-Pitch Ball Grid Array (FBGA) (Preliminary) Applications Note Select pins S0, S1, S2 are intended to be used as static user configurable control pins. The AC performance of these pins has not been characterized or tested. Switching of these select pins during system operation may temporarily disrupt output logic states and/or enable pin controls. Ordering Code: Order Number FSTU162450GX (Note 1) FSTU162450MTD (Note 2) Package Number BGA54A (Preliminary) MTD56 Package Description 54-Ball Fine-Pitch Ball Grid Array (FBGA), JEDEC MO-205, 5.5mm Wide [Tape and Reel] 56-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 6.1mm Wide Note 1: BGA package available in Tape and Reel only. Note 2: Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code. UHC is a trademark of Fairchild Semiconductor Corporation. © 2001 Fairchild Semiconductor Corporation DS500423 www.fairchildsemi.com FSTU162450 Configurable 4-Bit to 20-Bit Bus Switch with −2V Undershoot Protection and 25Ω Series Resistors in Outputs (Preliminary) February 2001 FSTU162450 Preliminary Connection Diagrams Pin Descriptions Pin Assignment for TSSOP Pin Name Description OE1, OE2 Bus Switch Enables 1A, 2A Bus A 1B, 2B Bus B S0 , S1 Bit Configuration Enables NC No Connect FBGA Pin Assignments Pin Assignment for FBGA (Top Thru View) www.fairchildsemi.com 2 1 2 3 4 5 6 A 1A3 1A2 OE1 OE2 1B2 1B3 B 1A5 1A4 1A1 1B1 1B4 1B5 C 1A7 1A6 GND OE5 1B6 1B7 D 1A9 1A8 GND VCC 1B8 1B9 E 2A1 1A10 S0 VCC 1B10 2B1 F 2A3 2A2 S1 GND 2B2 2B3 G 2A5 2A4 VCC GND 2B4 2B5 H 2A7 2A6 2A10 2B10 2B6 2B7 J 2A9 2A8 OE4 OE3 2B8 2B9 Preliminary FSTU162450 Logic Diagrams 20-Bit Configuration 10-Bit Configuration 5-Bit Configuration 4-Bit Configuration 3 www.fairchildsemi.com FSTU162450 Preliminary Functional Description The device can also be configured as an 8 and 16-bit device by grounding the unused pins in the 10-bit and 20-bit configurations respectively. The 8-bit configuration may also be achieved by connecting two of the 4-bit enables from the 4-bit configuration together and connecting the remaining enable pin (OE) HIGH. Truth Tables (see Functional Description) 20-Bit Configuration (S0 = S1 = L) Inputs Inputs/Outputs OE1 OE2 OE3 OE4 OE5 L X X X X 1A1-10 = 1B1-10, 2A1-10 = 2B1-10 H X X X X Z 10-Bit Configuration (S0 = L, S1 = H) Inputs Inputs/Outputs OE1 OE2 OE3 OE4 OE5 1A1-10 = 1B1-10 2A1-10 = 2B1-10 L X X L X 1AX = 1BX 2AX = 2BX L X X H X 1AX = 1BX Z H X X L X Z 2AX = 2BX H X X H X Z Z 5-Bit Configuration (S0 = H, S1 = L) Inputs Inputs/Outputs OE1 OE2 OE3 OE4 OE5 1A1-5, 1B1-5 1A6-10, 1B6-10 2A1-5, 2B1-5 2A5-10, 2B5-10 L L L L X 1Ax = 1Bx 1Ay = 1By 2Ax = 2Bx 2Ay = 2By L L L H X 1Ax = 1Bx 1Ay = 1By 2Ax = 2Bx Z L L H L X 1Ax = 1Bx 1Ay = 1By Z 2Ay = 2By L L H H X 1Ax = 1Bx 1Ay = 1By Z Z L H L L X 1Ax = 1Bx Z 2Ax = 2Bx 2Ay = 2By L H L H X 1Ax = 1Bx Z 2Ax = 2Bx Z L H H L X 1Ax = 1Bx Z Z 2Ay = 2By L H H H X 1Ax = 1Bx Z Z Z H L L L X Z 1Ay = 1By 2Ax = 2Bx 2Ay = 2By H L L H X Z 1Ay = 1By 2Ax = 2Bx Z H L H L X Z 1Ay = 1By Z 2Ay = 2By H L H H X Z 1Ay = 1By Z Z H H L L X Z Z 2Ax = 2Bx 2Ay = 2By H H L H X Z Z 2Ax = 2Bx Z H H H L X Z Z Z 2Ay = 2By H H H H X Z Z Z Z www.fairchildsemi.com 4 Preliminary (Continued) 4-Bit Configuration (S0 = S1 = H) Inputs Inputs/Outputs 1A9-10, 2B9-10 OE1 OE2 OE3 OE4 OE5 1A1-4, 1B1-4 1A5-8, 1B5-8 2A3-6, 2B3-6 2A7-10, 2B7-10 L L L L L 1Ax = 1Bx 1Ay = 1By 2Ax = 2Bx 2Ay = 2By L L L L H 1Ax = 1Bx 1Ay = 1By 2Ax = 2Bx 2Ay = 2By Z 1Az = 1Bz 2Az = 2Bz 2A1-2, 2B1-2 1Az = 1Bz 2Az = 2Bz L L L H L 1Ax = 1Bx 1Ay = 1By 2Ax = 2Bx Z L L L H H 1Ax = 1Bx 1Ay = 1By 2Ax = 2Bx Z Z 1Az = 1Bz 2Az = 2Bz L L H L L 1Ax = 1Bx 1Ay = 1By Z 2Ay = 2By L L H L H 1Ax = 1Bx 1Ay = 1By Z 2Ay = 2By Z 1Az = 1Bz 2Az = 2Bz L L H H L 1Ax = 1Bx 1Ay = 1By Z Z L L H H H 1Ax = 1Bx 1Ay = 1By Z Z Z 1Az = 1Bz 2Az = 2Bz L H L L L 1Ax = 1Bx Z 2Ax = 2Bx 2Ay = 2By L H L L H 1Ax = 1Bx Z 2Ax = 2Bx 2Ay = 2By Z 1Az = 1Bz 2Az = 2Bz L H L H L 1Ax = 1Bx Z 2Ax = 2Bx Z L H L H H 1Ax = 1Bx Z 2Ax = 2Bx Z Z 1Az = 1Bz 2Az = 2Bz L H H L L 1Ax = 1Bx Z Z 2Ay = 2By L H H L H 1Ax = 1Bx Z Z 2Ay = 2By Z 1Az = 1Bz 2Az = 2Bz L H H H L 1Ax = 1Bx Z Z Z L H H H H 1Ax = 1Bx Z Z Z Z 1Az = 1Bz 2Az = 2Bz H L L L L Z 1Ay = 1By 2Ax = 2Bx 2Ay = 2By H L L L H Z 1Ay = 1By 2Ax = 2Bx 2Ay = 2By Z 1Az = 1Bz 2Az = 2Bz H L L H L Z 1Ay = 1By 2Ax = 2Bx Z H L L H H Z 1Ay = 1By 2Ax = 2Bx Z Z 1Az = 1Bz 2Az = 2Bz H L H L L Z 1Ay = 1By Z 2Ay = 2By H L H L H Z 1Ay = 1By Z 2Ay = 2By Z 1Az = 1Bz 2Az = 2Bz H L H H L Z 1Ay = 1By Z Z H L H H H Z 1Ay = 1By Z Z Z 1Az = 1Bz 2Az = 2Bz H H L L L Z Z 2Ax = 2Bx 2Ay = 2By H H L L H Z Z 2Ax = 2Bx 2Ay = 2By Z 1Az = 1Bz 2Az = 2Bz H H L H L Z Z 2Ax = 2Bx Z H H L H H Z Z 2Ax = 2Bx Z Z 1Az = 1Bz 2Az = 2Bz H H H L L Z Z Z 2Ay = 2By H H H L H Z Z Z 2Ay = 2By Z H H H H L Z Z Z Z 1Az = 1Bz 2Az = 2Bz H H H H H Z Z Z Z Z 5 www.fairchildsemi.com FSTU162450 Truth Tables FSTU162450 Preliminary Absolute Maximum Ratings(Note 3) Supply Voltage (VCC ) −0.5V to +7.0V DC Switch Voltage (VS) (Note 4) −2.0V to +7.0V Recommended Operating Conditions (Note 6) Power Supply Operating (VCC) DC Input Control Pin Voltage −0.5V to +7.0V (VIN) (Note 5) DC Input Diode Current (lIK) VIN < 0V −50 mA DC Output (IOUT ) Current 128 mA 0V to 5.5V Switch Control Input 0 ns/V to 5 ns/V Switch I/O −65°C to +150 °C Storage Temperature Range (TSTG) 0V to 5.5V Output Voltage (VOUT) Input Rise and Fall Time (tr, tf) +/− 100 mA DC VCC/GND Current (ICC/IGND) 4.0V to 5.5V Input Voltage (VIN) 0 ns/V to DC Free Air Operating Temperature (TA) -40 °C to +85 °C Note 3: The “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. The device should not be operated at these limits. The parametric values defined in the Electrical Characteristics tables are not guaranteed at the absolute maximum rating. The “Recommended Operating Conditions” table will define the conditions for actual device operation. Note 4: VS is the voltage observed/applied at either the A or B Ports across the switch. Note 5: The input and output negative voltage ratings may be exceeded if the input and output diode current ratings are observed. Note 6: Unused control inputs must be held HIGH or LOW. They may not float. DC Electrical Characteristics VCC Symbol Parameter (V) TA = −40 °C to +85 °C Min Typ (Note 7) Max −1.2 Units Conditions IIN = −18 mA VIK Clamp Diode Voltage VIH HIGH Level Input Voltage 4.0-5.5 VIL LOW Level Input Voltage 4.0-5.5 0.8 V II Input Leakage Current 5.5 ±1.0 µA 0 ≤ VIN ≤ 5.5V 0 ±1.0 µA VIN = 5.5V ±1.0 µA 0 ≤ A, B ≤ VCC 4.5 2.0 V V IOZ OFF-STATE Leakage Current 5.5 RON Switch On Resistance 4.5 20 26 38 Ω VIN = 0V, IIN = 64 mA (Note 8) 4.5 20 27 40 Ω VIN = 0V, IIN = 30 mA 4.5 20 28 48 Ω VIN = 2.4V, IIN = 15 mA 4.0 20 30 48 Ω VIN = 2.4V, IIN = 15 mA ICC Quiescent Supply Current 5.5 3 µA VIN = VCC or GND, IOUT = 0 ∆ ICC Increase in ICC per Input 5.5 2.5 mA One Input at 3.4V VIKU Voltage Undershoot 5.5 −2.0 V Other Inputs at VCC or GND 0.0 mA ≥ IIN ≥ −50 mA OEx = 5.5V Note 7: Typical values are at VCC = 5.0V and T A = +25°C Note 8: Measured by the voltage drop between A and B pins at the indicated current through the switch. On Resistance is determined by the lower of the voltages on the two (A or B) pins. www.fairchildsemi.com 6 Preliminary TA = −40 °C to +85 °C, Symbol Parameter CL = 50pF, RU = RD = 500Ω VCC = 4.5 – 5.5V Min tPHL, tPLH Propagation Delay Bus-to-Bus (Note 9) tPZH, tPZL Output Enable Time 1.5 Max VCC = 4.0V Min Units Conditions Max 0.25 0.25 ns VI = OPEN Figures 2, 3 5.5 6.0 ns VI = 7V for tPZL Figures 2, 3 VI = OPEN for tPZH tPHZ, tPLZ Output Disable Time 1.5 5.5 6.0 VI = 7V for tPLZ ns VI = OPEN for tPHZ tPZH, tPZL Sel (S0, 1) to Output Enable Time 1.5 6.0 6.5 VI = 7V for tPZL ns VI = OPEN for tPZH tPHZ, tPLZ Sel (S0, 1) to Output Disable Time 1.5 Figure Number 6.0 6.5 VI = 7V for tPLZ ns VI = OPEN for tPHZ Figures 2, 3 Figures 2, 3 Figures 2, 3 Note 9: This parameter is guaranteed by design but is not tested. The bus switch contributes no propagation delay other than the RC delay of the typical On Resistance of the switch and the 50pF load capacitance, when driven by an ideal voltage source (zero output impedance). Capacitance Symbol (Note 10) Parameter Typ Max Units Conditions CIN Control Pin Input Capacitance 3 pF VCC = 5.0V, VIN = 0V CI/O Input/Output Capacitance “OFF State” 6 pF VCC, OE = 5.0V, VIN = 0V Note 10: TA = +25°C, f = 1 MHz, Capacitance is characterized but not tested. 7 www.fairchildsemi.com FSTU162450 AC Electrical Characteristics FSTU162450 Preliminary Undershoot Characteristic (Note 11) Symbol Parameter Output Voltage During Undershoot VOUTU Min Typ 2.5 VOH − 0.3 Max Units V Conditions Figure 1 Note 11: This test is intended to characterize the device’s protective capabilities by maintaining output signal integrity during an input transient voltage undershoot event. FIGURE 1. Device Test Conditions Parameter Value Units VIN see Waveform V R1 = R2 100K Ω VTRI 11.0 V VCC 5.5 V Transient Input Voltage (VIN) Waveform AC Loading and Waveforms Note: Input driven by 50Ω source terminated in 50Ω Note: CL includes load and stray capacitance Note: Input Frequency = 1.0 MHz, tW = 500 ns FIGURE 2. AC Test Circuit FIGURE 3. AC Waveforms www.fairchildsemi.com 8 Preliminary FSTU162450 Physical Dimensions inches (millimeters) unless otherwise noted 54-Ball Fine-Pitch Ball Grid Array (FBGA), JEDEC MO-205, 5.5mm Wide Package Number BGA54A Preliminary 9 www.fairchildsemi.com FSTU162450 Configurable 4-Bit to 20-Bit Bus Switch with −2V Undershoot Protection and 25Ω Series Resistors in Outputs (Preliminary) Preliminary Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 56-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 6.1mm Wide Package Number MTD56 Technology Description The Fairchild Switch family derives from and embodies Fairchild’s proven switch technology used for several years in its 74LVX3L384 (FST3384) bus switch product. Fairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and Fairchild reserves the right at any time without notice to change said circuitry and specifications. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. www.fairchildsemi.com www.fairchildsemi.com 10