1. Device Overview:

️· Device: Fairchild FST3245 (now part of ON Semiconductor)
️· Type: Bidirectional Bus Switch
️· Function: Connects or disconnects two buses (A and B) based on the /OE (Output Enable) signal.

2. Pin Descriptions:

️· 1 (NC): No Connection
️· 19 (/OE): Bus Switch Enable (Active LOW)
️· 2-9 (A0-A7): Bus A
️· 10 (GND): Ground
️· 11-18 (B7-B0): Bus B
️· 20 (VCC): Supply Voltage

3. Absolute Maximum Ratings:

️· VCC (Supply Voltage): -0.5 to +7.0 V
️· VS (DC Switch Voltage): -0.5 to +7.0 V
️· VIN (DC Input Voltage): -0.5 to +7.0 V
️· TSTG (Storage Temperature Range): -65 to +150 °C

4. Electrical Characteristics (Typical @ VCC = 4.5-5.5 V unless otherwise noted):

️· VIK (Clamp Diode Voltage): -1.2 V (at IIN = -18mA)
️· VIH (High-Level Input Voltage): 2.0 V
️· VIL (Low-Level Input Voltage): 0.8 V
️· IIN (Input Leakage Current): ±1.0 µA
️· IOZ (Off-state Leakage Current): ±1.0 µA
️· RON (Switch On Resistance): 4-8 Ohms (varies with current and VCC)
️· ICC (Quiescent Supply Current): 3 µA
️· ∆ICC (Increase in ICC per Input): 2.5 mA

5. AC Characteristics (Timing):

️· tPHL, tPLH (Bus-to-Bus Propagation Delay): 0.25 ns
️· tPZH, tPZL (Output Enable Time): 1.5 to 6.4 ns (depending on input voltage)
️· tPHZ, tPLZ (Output Disable Time): 1.5 to 5.7 ns (depending on input voltage)

6. Capacitance:

️· CIN (Control Pin Input Capacitance): 3 pF
️· CI/O (Input/Output Capacitance): 5 pF

7. Operating Conditions:

️· VCC (Power Supply Operating): 4.0 to 5.5 V (4.0V for reduced VCC)
️· TA (Operating Temperature, Free Air): -40 to +85 °C

8. Key Operational Notes
️· /OE is active LOW.
️· Low input voltage on the OE pin will connect the buses.
️· High input voltage on the OE pin will disconnect the buses.

9. Contact Information
️· N. American Technical Support: 800−282−9855 Toll Free
️· Europe, Middle East and Africa Technical Support: Phone: 421 33 790 2910
️· Japan Customer Focus Center: Phone: 81−3−5817−1050
️· Website : www.onsemi.com