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PI74LPT2Q245
Fast CMOS 3.3V 8-Bit Bidirectional Transceiver
Product Description
Pericom Semiconductor’s PI74LPT series of logic circuits are
produced in the Company’s advanced 0.6 micron CMOS technology
achieving high speed while maintaining low power operation.
The PI74LPT2Q245 is an 8-bit bidirectional transceiver designed
for asynchronous two-way communication between data buses.
The transmit/receive input pin (T/R) determines the direction of
data flow through the bidirectional transceiver. Transmit (active
HIGH) enables data from A ports to B ports, and receive (active
LOW) from B ports to A ports. The Output Enable (OE) input, when
HIGH, disables both A and B ports by placing them in HIGH Z
condition.
The PI74LPT2Q245 can be driven from either 3.3V or 5.0V devices
allowing this device to be used as a translator in a mixed 3.3V/5.0V
system.
Logic Block Diagram
Product Pin Configuration
Product Pin Description
Truth Table
(1)
Note:
1. H = High Voltage Level, X = Don't Care,
L = Low Voltage Level, Z = High Impedance
stupnI
)1(
stuptuO
)1(
EOR/T
LL AsuBotataDBsuB
LH BsuBotataDAsuB
HX ZetatShgiH
20-PIN
L20
Q20
R20
S20
emaNniPnoitpircseD
OE elbanEtuptuOetatS-3
)WOLevitcA(stupnI
R/TtupnIlortnoCnoitceriD
7A-0ArostupnIAediS
stuptuOetatS-3
7B-0BrostupnIBediS
stuptuOetatS-3
DNGdnuorG
V
CC
rewoP
Product Features
• Compatible with LCX™ and LVT™ families of products
• Supports 5V Tolerant Mixed Signal Mode Operation
– Input can be 3V or 5V
– Output can be 3V or connected to 5V bus
• Advanced Low Power CMOS Operation
• Excellent output drive capability:
Balanced drives (12 mA sink and source)
•33Ω Series Resistors on all outputs
• Low ground bounce outputs
• Hysteresis on all inputs
• Industrial operating temperature range: –40°C to +85°C
• Packages available:
– 20-pin 173 mil wide plastic TSSOP (L)
– 20-pin 150 mil wide plastic QSOP (Q)
– 20-pin 150 mil wide plastic TQSOP (R)
– 20-pin 300 mil wide plastic SOIC (S)
B
0
A
0
OE
T/R
B
1
A
1
B
2
A
2
B
3
A
3
B
4
A
4
B
5
1A5
B
6
A
6
B
7
A
7
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3.3V 8-BIT BIDIRECTIONAL TRANSCEIVER
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Maximum Ratings
(Above which the useful life may be impaired. For user guidelines, not tested.)
Note:
Stresses greater than those listed under MAXIMUM
RATINGS may cause permanent damage to the
device. This is a stress rating only and functional
operation of the device at these or any other conditions above those indicated in the operational
sections of this specification is not implied. Exposure
to absolute maximum rating conditions for extended
periods may affect reliability.
DC Electrical Characteristics (Over the Operating Range, TA = –40°C to +85°C, VCC = 2.7V to 3.6V)
Parameters Description Test Conditions
(1)
Min. Typ
(2)
Max. Units
VIH Input HIGH Voltage (Input pins) Guaranteed Logic HIGH Level 2.2 — 5.5 V
Input HIGH Voltage (I/O pins) 2.0 — 5.5 V
VIL Input LOW Voltage Guaranteed Logic LOW Level –0.5 — 0.8 V
(Input and I/O pins)
IIH Input HIGH Current (Input pins) VCC = Max. VIN = 5.5V — — ±1 µA
Input HIGH Current (I/O pins) VCC = Max. VIN = VCC ——±1µA
IIL Input LOW Current (Input pins) VCC = Max. VIN = GND — — ±1 µA
Input LOW Current (I/O pins) VCC = Max. VIN = GND — — ±1 µA
IOZH High Impedance Output Current VCC = Max. VOUT = 5.5V — — ±1 µA
IOZL (3-State Output pins) VCC = Max. VOUT = GND — — ±1 µA
VIK Clamp Diode Voltage VCC = Min., IIN = –18 mA — –0.7 –1.2 V
IODH Output HIGH Current V CC = 3.3V, V IN = VIH or VIL, VO = 1.5V
(3)
–20 — –60 mA
IODL Output LOW Current VCC = 3.3V, VIN = VIH or VIL, VO = 1.5V
(3)
20 — 60 mA
VOH Output HIGH Voltage VCC = MIN.IOH = –0.1 mA Vcc -0.2 — — V
VIN = VIH or VIL
VCC = 3.0V IOH = –8 mA 2.4
(5)
——V
VIN = VIH or VIL
VOL Output LOW Voltage VCC = Min. IOL = 0.1 mA — — 0.2 V
VIN = VIH or VIL IOL = 8 mA — — 0.5 V
IOS Short Circuit Current
(4)
VCC = Max.
(3)
, VOUT ≤ GND –40 — –100 mA
IOFF Power Down Disable VCC = 0V, VIN or VOUT ≤ 4.5V — — ±100 µA
VH Input Hysteresis — 150 — mV
Capacitance (TA = 25°C, f = 1 MHz)
Parameters
(1)
Description Test Conditions Typ. Max. Units
CIN Input Capacitance VIN = 0V 4.5 6 pF
COUT Output Capacitance VOUT = 0V 5.5 8 pF
Notes:
1. For Max. or Min. conditions, use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at Vcc = 3.3V, +25°C ambient and maximum loading.
3. Not more than one output should be shorted at one time. Duration of the test should not exceed one second.
4. This parameter is guaranteed but not tested.
Note:
1. This parameter is determined by device characterization but is not production tested.
Storage Temperature .......................................................... –65°C to +150°C
Ambient Temperature with Power Applied ......................... –40°C to +85°C
Supply Voltage to Ground Potential (Inputs & Vcc Only) .. –0.5V to +7.0V
Supply Voltage to Ground Potential (Outputs & D/O Only) –0.5V to +7.0V
DC Input Voltage .................................................................. –0.5V to +7.0V
DC Output Current ............................................................................ 120 mA
Power Dissipation ..................................................................................1.0W
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PI74LPT2Q245
3.3V 8-BIT BIDIRECTIONAL TRANSCEIVER
Power Supply Characteristics
Parameters Description Test Conditions
(1)
Min. Typ
(2)
Max. Units
ICC Quiescent Power Supply Current VCC = Max. VIN = GND or VCC 0.1 10 µA
∆ICC Quiescent Power Supply Current VCC = Max. VIN = VCC – 0.6V
(3)
2.0 30 µA
TTL Inputs HIGH
ICCD Dynamic Power Supply
(4)
VCC = Max., VIN = VCC 50 75 µA/
Outputs Open VIN = GND MHz
OE = GND
One Bit Toggling
50% Duty Cycle
IC Total Power Supply V CC = Max., VIN = VCC – 0.6V 0.6 2.3 mA
Current
(6)
Outputs Open VIN = GND
fI = 10 MHZ
50% Duty Cycle
OE = GND
One Bit Toggling
VCC = Max., VIN = VCC – 0.6V 2.1 4.7
(5)
Outputs Open VIN = GND
fI = 2.5 MHZ
50% Duty Cycle
OE = GND
8 Bits Toggling
Notes:
1. For Max. or Min. conditions, use appropriate value specified under Electrical Characteristics for the applicable device.
2. Typical values are at Vcc = 3.3V, +25°C ambient.
3. Per TTL driven input; all other inputs at Vcc or GND.
4. This parameter is not directly testable, but is derived for use in Total Power Supply Calculations.
5. Values for these conditions are examples of the Icc formula. These limits are guaranteed but not tested.
6. IC =IQUIESCENT + IINPUTS + IDYNAMIC
IC = ICC + ∆ICC DHNT + ICCD (fCP/2 + fINI)
ICC = Quiescent Current (ICCL, ICCH and ICCZ)
∆ICC = Power Supply Current for a TTL High Input
DH = Duty Cycle for TTL Inputs High
NT = Number of TTL Inputs at DH
ICCD = Dynamic Current Caused by an Input Transition Pair (HLH or LHL)
fCP = Clock Frequency for Register Devices (Zero for Non-Register Devices)
NCP = Number of Clock Inputs at fCP
fI = Input Frequency
NI = Number of Inputs at fI
All currents are in milliamps and all frequencies are in megahertz.
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PI74LPT2Q245
3.3V 8-BIT BIDIRECTIONAL TRANSCEIVER
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Pericom Semiconductor Corporation
2380 Bering Drive • San Jose, CA 95131 • 1-800-435-2336 • Fax (408) 435-1100 • http://www.pericom.com
Notes:
1. Propagation Delays and Enable/Disable times are with Vcc = 3.3V ±0.3V, normal range. For Vcc = 2.7V,
extended range, all Propagation Delays and Enable/Disable times should be degraded by 20%.
2. See test circuit and waveforms.
3. Minimum limits are guaranteed but not tested on Propagation Delays.
4. This parameter is guaranteed but not production tested.
5. Skew between any two outputs, of the same package, switching in the same direction. This parameter is
guaranteed by design.
Switching Characteristics over Operating Range
(1)
LPT2Q245 LPT2Q245A
Com. Com.
Parameters Description Conditions
(2)
Min.
(3)
Max. Min.
(3)
Max.
tPLH Propagation Delay CL = 50 pF 1.5 7.0 1.5 4.6 ns
tPHL A to B, B to A RL = 500
Ω
tPZH Output Enable Time 1.5 8.5 1.5 6.2 ns
tPZL OE to A or B
tPHZ Output Disable Time
(4)
1.5 7.5 1.5 5.0 ns
tPLZ OE to A or B
tPZH Output Enable Time 1.5 8.5 1.5 6.2 ns
tPZL T/R to A or B
tPHZ Output Disable Time
(4)
1.5 7.5 1.5 5.0 ns
tPLZ T/R to A or B
tSK(o) Output Skew
(5)
0.5 0.5 ns
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