Document
HD74LVC245A
Octal Bidirectional Transceivers with 3-state Outputs
ADE-205-111B(Z) 3rd Edition December 1996 Description
The HD74LVC245A has eight buffers with three state outputs in a 20 pin package. When (T / R ) is high, data flows from the A inputs to the B outputs, and when (T / R ) is low, data flows from the B inputs to the A outputs. A and B bus are separated by making enable input ( OE) high level. Low voltage and high speed operation is suitable at the battery drive product (note type personal computer) and low power consumption extends the life of a battery for long time operation.
Features
• • • • • • VCC = 2.0 V to 5.5 V All inputs VIH (Max.) = 5.5 V (@VCC = 0 V to 5.5 V) All input outputs VI/O (Max.) = 5.5 V (@VCC = 0 V or output off state) Typical VOL ground bounce < 0.8 V (@VCC = 3.3 V, Ta = 25°C) Typical VOH undershoot > 2.0 V (@VCC = 3.3 V, Ta = 25°C) High output current ±24 mA (@VCC = 3.0 V to 5.5 V)
Function Table
Inputs OE L L H H: L: X: Z: High level Low level Immaterial High impedance T/R L H X Operation B data to A bus A data to B bus Z
HD74LVC245A
Pin Arrangement
T/R 1 A0 2 A1 3 A2 4 A3 5 A4 6 A5 7 A6 8 A7 9 GND 10
20 VCC 19 OE 18 B0 17 B1 16 B2 15 B3 14 B4 13 B5 12 B6 11 B7
(Top view)
Absolute Maximum Ratings
Item Supply voltage Input diode current Input voltage Output diode current Symbol VCC I IK VI I OK Ratings –0.5 to 6.0 –50 –0.5 to 6.0 –50 50 Input / output voltage VI/O –0.5 to VCC +0.5 –0.5 to 6.0 Output current VCC, GND current / pin Storage temperature IO I CC or IGND Tstg ±50 100 –65 to 150 Unit V mA V mA mA V V mA mA °C VI = –0.5 V T / R, OE VO = –0.5 V VO = VCC +0.5 V Output "H" or "L" Output "Z" or VCC:OFF Conditions
Note: The absolute maximum ratings are values which must not individually be exceeded, and furthermore, no two of which may be realized at the same time.
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HD74LVC245A
Recommended Operating Conditions
Item Supply voltage Symbol VCC Ratings 1.5 to 5.5 2.0 to 5.5 Input / output voltage VI VI/O 0 to 5.5 0 to V CC 0 to 5.5 Operating temperature Output current Ta I OH –40 to 85 –12 –24 I OL
*1 *2
Unit V V V V V °C mA mA mA mA ns/V
Conditions Data retention At operation T / R, OE Output "H" or "L" Output "Z" or VCC:OFF
VCC = 2.7 V VCC = 3.0 V to 5.5 V VCC = 2.7 V VCC = 3.0 V to 5.5 V
12 24
*2
Input rise / fall time
t r, t f
10
Notes: 1. This item guarantees maximum limit when one input switches. Waveform : Refer to test circuit of switching characteristics. 2. duty cycle ≤ 50%
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HD74LVC245A
Electrical Characteristics
Ta = –40 to 85°C Item Input voltage Symbol VCC (V) VIH Min Max — Unit V V V I OH = –100 µA I OH = –12 mA Test Conditions
2.7 to 3.6 2.0
4.5 to 5.5 VCC×0.7 — VIL 2.7 to 3.6 — 4.5 to 5.5 — Output voltage VOH 0.8
VCC×0.3 V V V V V V V V V V µA µA µA µA µA µA VIN = 5.5 V or GND VIN = VCC, GND VOUT = 5.5 V or GND VIN / V OUT = 5.5 V VIN / V OUT = 3.6 to 5.5 V VIN = VOUT or GND VIN = one input at (VCC –0.6)V, other inputs at V CC or GND I OL = 100 µA I OL = 12 mA I OL = 24 mA I OH = –24 mA
2.7 to 5.5 VCC –0.2 — 2.7 3.0 3.0 4.5 2.2 2.4 2.2 3.8 — — — — 0.2 0.4 0.55 0.55 ±5.0 ±5.0 20 ±10 10 500
VOL
2.7 to 5.5 — 2.7 3.0 4.5 — — — —
Input current Off state output current
I IN I OZ I OFF
0 to 5.5
2.7 to 5.5 —
Output leak current
0
—
Quiescent supply current I CC ∆ I CC
2.7 to 3.6 — 2.7 to 5.5 — 3.0 to 3.6 —
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HD74LVC245A
Switching Characteristics
Ta = –40 to 85°C Item Propagation delay time Symbol VCC (V) t PLH t PHL 2.7 3.3±0.3 5.0±0.5 Output enable time t ZH t ZL 2.7 3.3±0.3 5.0±0.5 Output disable time t ZH t LZ
*1
Min — 1.5 — — 1.5 — — 1.5 — — — — — —
Typ — — — — — — — — — — — — 3.0 15.0
Max 8.0 7.0 5.5 9.5 8.5 7.0 8.5 7.5 6.5 — 1.0 1.0 — —
Unit ns ns ns ns ns ns ns ns ns ns ns ns pF pF
From (Input) To (Output) A or B B or A
OE
A or B
2.7 3.3±0.3 5.0±0.5
OE
A or B
Between outut pins skew
t OSLH t OSHL
2.7 3.3±0.3 5.0±0.5
Input capacitance Output capacitance Note:
CIN CO
2.7 2.7
1. This parameter is characterized but not tested. tosLH = | tPLHm - tPLHn |, tosHL = | tPHLm - tPHLn|
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HD74LVC245A
Test Circuit
VCC VCC
OE See Function Table Input Pulse Generator Zout = 50 Ω Output A0 B0 CL = 50 pF T/R S2
Vcc=2.7V, 3.3±0.3V Vcc=5.0±0.5V
S1 500 Ω 450 Ω 50 Ω Scope S2 OPEN See under table GND
*1
Symbol t PLH / t PHL t ZH/ t HZ t ZL / t LZ Note: 1. CL includes probe and jig capacitance.
OPEN GND 6V
OPEN GND 2×Vcc
Waveforms – 1
tr 90 % Input Vref 10 % t PLH Vref 90 % Vref 10 % t PHL VOH In phase output Vref VOL tf VIH GND
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HD74LVC245A
Waveforms – 2
tf OE 90 % Vref 10 % t ZL Waveform - A t ZH Waveform - B Vref Vref t HZ VOH – 0.3 V tr 90 % Vref 10 % t LZ VIH GND ≈V OH1 VOL + 0.3 V VOL VOH ≈V OL1 TEST VIH Vref VOH1 VOL1 Notes: 1. 2. 3. 4.
Vcc=2.7V, 3.3±0.3V Vcc=5.0±0.5V
2.7 V 1.5 V 3V GND
Vcc 50%Vcc Vcc GND
tr = 2.5 ns, tf = 2.5 ns Input waveform : PRR = 10 MHz, duty cycle 50% Waveform – A shows input conditions such that the output is "L" level when enable by the output control. Waveform – B shows input.