Document
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
December 2013
74LCX245 Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Features
■ 5V tolerant inputs and outputs ■ 2.3V to 3.6V VCC specifications provided ■ 7.0ns tPD max. (VCC = 3.3V), 10µA ICC max. ■ Power down high impedance inputs and outputs ■ Supports live insertion/withdrawal(1) ■ ±24mA output drive (VCC = 3.0V) ■ Implements proprietary noise/EMI reduction circuitry ■ Latch-up performance exceeds 500mA ■ ESD performance:
– Human body model > 2000V – Machine model > 200V ■ Leadless DQFN package
Note: 1. To ensure the high-impedance state during power up
or down, OE should be tied to VCC through a pull-up resistor: the minimum value or the resistor is determined by the current-sourcing capability of the driver.
General Description
The LCX245 contains eight non-inverting bidirectional buffers with 3-STATE outputs and is intended for bus oriented applications. The device is designed for low voltage (2.5V and 3.3V) VCC applications with capability of interfacing to a 5V signal environment. The T/R input determines the direction of data flow through the device. The OE input disables both the A and B ports by placing them in a high impedance state.
The LCX245 is fabricated with an advanced CMOS technology to achieve high speed operation while maintaining CMOS low power dissipation.
Ordering Information
Order Number
Package Number
Package Description
74LCX245WM
M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300" Wide
74LCX245SJ
M20D 20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
74LCX245BQX(2)
MLP20B 20-Terminal Depopulated Quad Very-Thin Flat Pack No Leads (DQFN), JEDEC MO-241, 2.5 x 4.5mm
74LCX245MSA
MSA20 20-Lead Shrink Small Outline Package (SSOP), JEDEC MO-150, 5.3mm Wide
74LCX245MTC
MTC20 20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
Note: 2. DQFN package available in Tape and Reel only.
Device also available in Tape and Reel. Specify by appending suffix letter “X” to the ordering number.
All packages are lead free per JEDEC: J-STD-020B standard.
©1994 Fairchild Semiconductor Corporation 74LCX245 Rev. 1.11.1
www.fairchildsemi.com
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Connection Diagrams
Pin Assignments for SOIC, SOP, SSOP, and TSSOP
Logic Symbol
Pin Assignment for DQFN
Truth Table
Inputs
OE T/R
Outputs
L L Bus B0 – B7 Data to Bus A0 – A7 L H Bus A0 – A7 Data to Bus B0 – B7 H X HIGH Z State on A0 – A7, B0 – B7(3)
H = HIGH Voltage Level L = LOW Voltage Level X = Immaterial Z = High Impedance
Note: 3. Unused bus terminals during HIGH Z State must be
held HIGH or LOW.
Logic Diagram
(Top Through View)
(Bottom View)
Pin Description
Pin Names
Description
OE Output Enable Input
T/R Transmit/Receive Input
A0–A7 B0–B7 DAP
Side A Inputs or 3-STATE Outputs Side B Inputs or 3-STATE Outputs No Connect
Note: DAP (Die Attach Pad)
©1994 Fairchild Semiconductor Corporation 74LCX245 Rev. 1.11.1
2
www.fairchildsemi.com
74LCX245 — Low Voltage Bidirectional Transceiver with 5V Tolerant Inputs and Outputs
Absolute Maximum Ratings
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only.
Symbol
Parameter
VCC Supply Voltage VI DC Input Voltage VO DC Output Voltage
Output in 3-STATE Output in HIGH or LOW State(4)
IIK IOK
IO ICC IGND TSTG
DC Input Diode Current, VI < GND DC Output Diode Current
VO < GND VO > VCC DC Output Source/Sink Current DC Supply Current per Supply Pin DC Ground Current per Ground Pin Storage Temperature
Note: 4. IO Absolute Maximum Rating must be observed.
Rating –0.5V to +7.0V –0.5V to +7.0V
–0.5V to +7.0V –0.5V to VCC + 0.5V
–50mA
–50mA +50mA ±50mA ±100mA ±100mA –65°C to +150°C
Recommended Operating Conditions(5)
The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to absolute maximum ratings.
Symbol
Parameter
VCC Supply Voltage Operating
Data Retention
VI Input Voltage VO Output Voltage
3-STATE
HIGH or LOW State
IOH / IOL
TA ∆t / ∆V
Output Current VCC = 3.0V–3.6V VCC = 2.7V–3.0V VCC = 2.3V–2.7V
Free-Air Operating Temperature
Input Edge Rate, VIN = 0.8V–2.0V, VCC = 3.0V
Note: 5. Unused inputs must be held HIGH or LOW. They may not float.
Min. 2.0 1.5 0 0 0
–40 0
Max.
3.6 3.6 5.5
5.5 VCC
±24 ±12 ±8 85 10
Units V V V
mA
°C ns /V
©1994 Fairchild Semiconductor Corporation 74LCX245 Rev. 1..