Philips Semiconductors Product specification 8-input multiplexer (3-State) 74F251A FEATURES PIN CONFIGURATION • High speed 8-to-1 multiplexing • On chip decoding • Multifunction capability • Inverting and Non-Inverting outputs • Both outputs are 3-State for further multiplexer expansion DESCRIPTION The 74F251A is a logic implementation of a single 8-position switch with the switch position controlled by the state of three Select (S0, S1, S2) inputs. True (Y) and complementary (Y) outputs are both provided. The output enable (OE) is active Low. When OE is High, both outputs are in High impedance state, allowing multiple output connections to a common bus without driving nor loading the bus significantly. All but one device must be in High impedance state to avoid high currents that would exceed the maximum ratings when the outputs of the 3-State devices are tied together. When the output of more than one device is tied together the user must ensure that there is no overlap in the active Low portion of the output enable voltages. I3 1 16 VCC I2 2 15 I4 I1 3 14 I5 I0 4 13 I6 Y 5 12 I7 Y 6 11 S0 OE 7 10 S1 GND 8 9 S2 SF00778 TYPE TYPICAL PROPAGATION DELAY TYPICAL SUPPLY CURRENT (TOTAL) 4.5ns 19mA 74F251A ORDERING INFORMATION ORDER CODE DESCRIPTION COMMERCIAL RANGE VCC = 5V ±10%, Tamb = 0°C to +70°C PKG DWG # 16-pin plastic DIP N74F251AN SOT38-4 16-pin plastic SO N74F251AD SOT162-1 INPUT AND OUTPUT LOADING AND FAN-OUT TABLE PINS DESCRIPTION 74F (U.L.) HIGH/LOW LOAD VALUE HIGH/LOW Data inputs 1.0/1.0 20µA/0.6mA Select inputs 1.0/1.0 20µA/0.6mA OE Output Enable input (active Low) 1.0/1.0 20µA/0.6mA Y, Y Data outputs 150/40 3mA/24mA I0–I7 S0–S2 NOTE: One (1.0) FAST unit load is defined as: 20µA in the High state and 0.6mA in the Low state. LOGIC SYMBOL IEC/IEEE SYMBOL 4 3 2 1 15 14 13 12 7 MUX EN 11 10 I0 11 S0 10 S1 9 S2 7 OE I1 I2 I3 I4 I5 I6 9 I7 0 G 0 7 5 2 4 3 6 2 1 Y Y 15 14 13 VCC = Pin 16 GND = Pin 8 5 12 6 SF00779 1996 Jan 05 SF00780 1 853–0358 16191 Philips Semiconductors Product specification 8-input multiplexer (3-State) 74F251A LOGIC DIAGRAM I0 I1 4 S0 S1 S2 I2 3 I3 2 I4 1 I5 15 I6 14 I7 13 12 11 10 9 7 OE 5 VCC = Pin 16 GND = Pin 8 Y SF00781 FUNCTION TABLE INPUTS OUTPUTS S2 S1 S0 OE X X X H Z Z L L L L I0 I0 L L H L I1 I1 L H L L I2 I2 L H H L I3 I3 H L L L I4 I4 H L H L I5 I5 H H L L I6 I6 Y Y H H H L I7 I7 NOTES: H = High voltage level L = Low voltage level X = Don’t care Z = High impedance “off” state 1996 Jan 05 6 Y 2 Philips Semiconductors Product specification 8-input multiplexer (3-State) 74F251A ABSOLUTE MAXIMUM RATINGS (Operation beyond the limit set forth in this table may impair the useful life of the device. Unless otherwise noted these limits are over the operating free air temperature range.) PARAMETER SYMBOL RATING UNIT VCC Supply voltage –0.5 to +7.0 V VIN Input voltage –0.5 to +7.0 V IIN Input current –30 to +5 mA VOUT Voltage applied to output in High output state –0.5 to VCC V IOUT Current applied to output in Low output state 48 mA Tamb Operating free-air temperature range 0 to +70 °C Tstg Storage temperature –65 to +150 °C RECOMMENDED OPERATING CONDITIONS SYMBOL LIMITS PARAMETER MIN NOM MAX 5.0 5.5 UNIT VCC Supply voltage 4.5 V VIH High-level input voltage 2.0 VIL Low-level input voltage 0.8 V IIK Input clamp current –18 mA IOH High-level output current –3 mA IOL Low-level output current 24 mA Tamb Operating free-air temperature range 70 °C V 0 DC ELECTRICAL CHARACTERISTICS (Over recommended operating free-air temperature range unless otherwise noted.) SYMBOL LIMITS TEST CONDITIONS1 PARAMETER VCC = MIN, VIL = MAX, VIH = MIN, IOH = MAX VOH High-level output voltage VOL Low-level output voltage VCC = MIN, VIL = MAX, VIH = MIN, IOL = MAX VIK Input clamp voltage VCC = MIN, II = IIK II Input current at maximum input voltage IIH MIN ±10%VCC 2.4 ±5%VCC 2.7 ±10%VCC TYP2 MAX UNIT V 3.3 V 0.35 0.50 V 0.35 0.50 V –0.73 –1.2 V VCC = MAX, VI = 7.0V 100 µA High-level input current VCC = MAX, VI = 2.7V 20 µA IIL Low-level input current VCC = MAX, VI = 0.5V –0.6 mA IOZH Off-state output current High-level voltage applied VCC = MAX, VI = 2.7V 50 µA IOZL Off-state output current Low-level voltage applied VCC = MAX, VI = 0.5V –50 mA IOS Short-circuit output current3 VCC = MAX –150 mA 20 27 mA ICC Supply S pply current ((total) l)) 17 24 mA 21 29 mA –60 ICCH ICCL ±5%VCC VCC = MAX ICCZ NOTES: 1. For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions for the applicable type. 2. All typical values are at VCC = 5V, Tamb = 25°C. 3. Not more than one output should be shorted at a time. For testing IOS, the use of high-speed test apparatus and/or sample-and-hold techniques are preferable in order to minimize internal heating and more accurately reflect operational values. Otherwise, prolonged shorting of a High output may raise the chip temperature well above normal and thereby cause invalid readings in other parameter tests. In any sequence of parameter tests, IOS tests should be performed last. 1996 Jan 05 3 Philips Semiconductors Product specification 8-input multiplexer (3-State) 74F251A AC ELECTRICAL CHARACTERISTICS LIMITS SYMBOL TEST CONDITION PARAMETER VCC = +5V ± 10% Tamb = 0°C to +70°C CL = 50pF RL = 500Ω VCC = +5V Tamb = +25°C CL = 50pF RL = 500Ω MIN TYP MAX MIN MAX UNIT tPLH tPHL Propagation delay In to Y Waveform 2 3.0 3.0 5.0 5.0 7.0 7.0 2.5 3.0 8.0 8.0 ns tPLH tPHL Propagation delay In to Y Waveform 1 2.5 1.0 4.5 2.5 7.0 5.0 2.0 1.0 7.5 5.0 ns tPLH tPHL Propagation delay Sn to Y Waveform 1 Waveform 2 4.5 4.0 6.5 5.5 10.0 9.0 4.0 3.5 11.5 9.5 ns tPLH tPHL Propagation delay Sn to Y Waveform 1 Waveform 2 3.5 2.5 6.0 4.5 9.0 7.0 3.5 2.5 9.5 7.5 ns tPZH tPZL Output Enable time OE to Y Waveform 3 Waveform 4 3.5 3.5 5.5 5.0 7.5 7.5 3.0 3.0 8.5 8.0 ns tPHZ tPLZ Output Disable time OE to Y Waveform 3 Waveform 4 2.5 1.0 4.0 4.0 6.5 6.0 2.0 1.0 7.0 6.5 ns tPZH tPZL Output Enable time OE to Y Waveform 3 Waveform 4 2.5 2.5 4.0 4.0 6.5 6.5 2.0 2.5 7.0 7.0 ns tPHZ tPLZ Output Disable time OE to Y Waveform 3 Waveform 4 3.5 1.0 5.0 2.0 7.5 4.5 3.0 1.0 8.0 4.5 ns AC WAVEFORMS For all waveforms, VM = 1.5V VIN VIN VM tPHL VOUT VM VM tPLH tPLH VM VM VM tPHL VM VOUT VM SF00782 SF00092 Waveform 1. For Inverting Outputs OE VM Waveform 2. For Non-Inverting Outputs VM tPZH OE VM VM tPZL tPHZ tPLZ VOH –0.3V Y, Y Y, Y VM 0V VM VOL +0.3V SF00784 SF00785 Waveform 3. 3-State Output Enable Time to High Level and Output Disable Time from High Level Waveform 4. 3-State Output Enable Time to Low Level and Output Disable Time from Low Level 1996 Jan 05 4 Philips Semiconductors Product specification 8-input multiplexer (3-State) 74F251A TEST CIRCUIT AND WAVEFORMS VCC 7.0V VIN RL VOUT PULSE GENERATOR tw 90% NEGATIVE PULSE VM CL AMP (V) VM 10% D.U.T. RT 90% 10% tTHL (tf ) tTLH (tr ) tTLH (tr ) tTHL (tf ) 0V RL AMP (V) 90% 90% Test Circuit for 3-State Outputs POSITIVE PULSE VM VM 10% TEST tPLZ tPZL All other SWITCH closed closed open DEFINITIONS: RL = Load resistor; see AC electrical characteristics for value. CL = Load capacitance includes jig and probe capacitance; see AC electrical characteristics for value. RT = Termination resistance should be equal to ZOUT of pulse generators. 10% tw SWITCH POSITION 0V Input Pulse Definition INPUT PULSE REQUIREMENTS family amplitude VM 74F 3.0V 1.5V rep. rate tw tTLH tTHL 1MHz 500ns 2.5ns 2.5ns SF00777 1996 Jan 05 5