Revised December 2001 FST34X2245 32-Bit Bus Switch with 25Ω Series Resistors in Outputs General Description Features The Fairchild Switch FST34X2245 provides 32-bits of high speed CMOS TTL-compatible bus switching in a standard flow-through mode. The low On Resistance of the switch allows inputs to be connected to outputs without adding propagation delay or generating additional ground bounce noise. ■ 25Ω switch connection between two ports The device is organized as a 32-bit switch. When OE is LOW, the switch is ON and Port A is connected to Port B. When OE is HIGH, the switch is OPEN and a high-impedance state exists between the two ports. ■ 32-bit version of FST32245 ■ Minimal propagation delay through the switch ■ Low lCC ■ Zero bounce in flow-through mode ■ Control inputs compatible with TTL level ■ Packaged in 20.5mm 80-lead package The FST34X2245 has equivalent 25Ω series resistors to reduce signal-reflection noise, eliminating the need for external terminating resistors. Ordering Code: Order Number Package Number FST34X2245QSP MQA80A Package Description 80-Lead, QVSOP, JEDEC MO-154, 0.150" Wide Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code. Logic Diagram © 2001 Fairchild Semiconductor Corporation DS500594 www.fairchildsemi.com FST34X2245 32-Bit Bus Switch with 25Ω Series Resistors in Outputs December 2001 FST34X2245 Connection Diagram Pin Descriptions Pin Name Description OEn Bus Switch Enable An Bus A Bn Bus B NC No Connect Function Table Input OEn www.fairchildsemi.com 2 Function L Connect H Disconnect Recommended Operating Conditions (Note 3) Supply Voltage (VCC) −0.5V to +7.0V DC Switch Voltage (VS) −0.5V to +7.0V Power Supply Operating (VCC) DC Input Voltage (VIN) (Note 2) −0.5V to +7.0V Input Voltage (VIN) 0V to 5.5V 0V to 5.5V DC Input Diode Current (lIK) VIN < 0V −50mA Output Voltage (VOUT) DC Output (IOUT) Sink Current 128mA Input Rise and Fall Time (tr, tf) +/− 100mA DC VCC/GND Current (ICC/IGND) Storage Temperature Range (TSTG) 4.0V to 5.5V Switch Control Input −65°C to +150 °C 0 ns/V to 5 ns/V Switch I/O 0 ns/V to DC −40 °C to +85 °C Free Air Operating Temperature (TA) Note 1: 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 2: The input and output negative voltage ratings may be exceeded if the input and output diode current ratings are observed. Note 3: Unused control inputs must be held HIGH or LOW. They may not float. DC Electrical Characteristics Symbol Parameter VCC (V) TA = −40 °C to +85 °C Min Typ (Note 4) Max Units −1.2 V 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 10 µA VIN = 5.5V ±1.0 µA 0 ≤ A, B ≤ VCC 38 Ω VIN = 0V, IIN = 64 mA VIN = 0V, IIN = 30 mA 4.5 IOZ OFF-STATE Leakage Current 5.5 RON Switch On Resistance 4.5 (Note 5) 2.0 V 20 26 4.5 20 27 40 Ω 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 (Note 6) 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 (Note 7) Other Inputs at VCC or GND Note 4: Typical values are at VCC = 5.0V and TA = +25°C Note 5: 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. Note 6: Per VCC pin. Note 7: Per TTL input, control pins only. 3 www.fairchildsemi.com FST34X2245 Absolute Maximum Ratings(Note 1) FST34X2245 AC Electrical Characteristics TA = −40 °C to +85 °C, CL = 50pF, RU = RD = 500Ω Symbol Parameter VCC = 4.5 – 5.5V Min tPHL, tPLH Propagation Delay Bus to Bus (Note 8) tPZH, tPZL Output Enable Time 1.0 VCC = 4.0V Max Min Units Conditions Figure Number Max 1.25 1.25 ns VI = OPEN Figures 1, 2 5.9 6.4 ns VI = 7V for tPZL Figures 1, 2 VI = OPEN for tPZH tPHZ, tPLZ Output Disable Time 1.0 6.0 5.7 ns VI = 7V for tPLZ VI = OPEN for tPHZ Figures 1, 2 Note 8: 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 the source (zero output impedance). Capacitance Symbol (Note 9) Parameter Typ Max Units Conditions CIN Control Pin Input Capacitance 3 pF VCC = 5.0V CI/O Input/Output Capacitance 5 pF VCC, OE = 5.0V Note 9: TA = +25°C, f = 1 MHz, Capacitance is characterized but not tested. AC Loading and Waveforms Note: Input driven by 50 Ω source terminated in 50 Ω Note: CL includes load and stray capacitance Note: Input PRR = 1.0 MHz tW = 500 ns FIGURE 1. AC Test Circuit FIGURE 2. AC Waveforms www.fairchildsemi.com 4 FST34X2245 32-Bit Bus Switch with 25Ω Series Resistors in Outputs Physical Dimensions 80-Lead, QVSOP, JEDEC MO-154, 0.150" Wide Package Number MQA80A 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 5 www.fairchildsemi.com