OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS WS74HC245 D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Drive Bus Lines Directly or Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC D D D Typical tpd = 12 ns ±6-mA Output Drive at 5 V Low Input Current of 1 µA Max N, NS, PACKAGE (TOP VIEW) DIR A1 A2 A3 A4 A5 A6 A7 A8 Vss 1 20 2 19 3 18 4 17 5 16 6 15 7 14 8 13 9 12 10 11 VDD OE B1 B2 B3 B4 B5 B6 B7 B8 description/ordering information These octal bus transceivers are designed for asynchronous bi-direction communication between data buses. The control-function implementation minimizes external timing requirements. The devices allow data transmission from the A bus to the B bus or from the B bus to the A bus, depending on the logic level at the direction-control (DIR) input. The output-enable (OE) input can be used to disable the device so that the buses are effectively isolated. ORDERING INFORMATION PACKAGE† TA 85°C C –40°C –40 C to 85 ORDERABLE PART NUMBER TOP-SIDE MARKING PDIP – N Tube of 20 WS74HC245N WS74HC245N SOP – NS Reel of 2000 WS74HC245NSR HC245 HC245 1 OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS WS74HC245 FUNCTION TABLE INPUTS OE DIR OPERATION L L B data to A bus L H A data to B bus H X Isolation logic diagram (positive logic) DIR 1 19 A1 OE 2 18 B1 To Seven Other Channels absolute maximum ratings over operating free-air temperature range (unless otherwise noted)† Supply voltage range, VDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 7 V Input clamp current, IIK (VI < 0 or VI > VDD) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20 mA Output clamp current, IOK (VO < 0 or VO > VDD) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20 mA Continuous output current, IO (VO = 0 to VDD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±35 mA Continuous current through VDD or Vss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .±70 mA Package thermal impedance, θJA (see Note 2): N package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69°C/W NS package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60°C/W ................................. Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to 150°C † Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. NOTES: 1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed. 2. The package thermal impedance is calculated in accordance with JESD 51-7. 2 OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS WS74HC245 recommended operating conditions (see Note 3) WS74HC245 VDD VIH Supply voltage VDD = 2 V VDD = 4.5 V High-level input voltage VI VO ∆t/∆v t/ v Low-level input voltage NOM MAX 2 5 6 V V 3.15 4.2 0.5 VDD = 4.5 V VDD = 6 V 1.35 V 1.8 Input voltage 0 Output voltage 0 VDD = 2 V VDD = 4.5 V Input transition rise/fall time UNIT 1.5 VDD = 6 V VDD = 2 V VIL MIN VDD VDD V V 1000 500 VDD = 6 V TA Operating free-air temperature NOTE 3: All unused inputs of the device must be held at VDD or Vss to ensure proper device operation. ns 400 –40 85 °C DC ELECTRICAL CHARACTERISTICS electrical characteristics over recommended operating free-air temperature range (unless otherwise noted) PARAMETER VOH TEST CONDITIONS ICC Ci A or B MAX UNIT 1.9 1.998 1.9 4.4 4.499 4.4 6V 5.9 5.999 5.9 IOH = –6 mA IOH = –7.8 mA 4.5 V 3.98 4.3 3.84 6V 5.48 5.8 5.34 2V 0.002 0.1 0.1 IOL = 20 µA A 4.5 V 0.001 0.1 0.1 6V 0.001 0.1 0.1 4.5 V 0.17 0.26 0.33 6V 0.15 0.26 0.33 6V ±0.1 ±100 ±1000 nA 6V ±0.01 ±0.5 ±5 µA 8 80 µA 10 10 pF VI = VDD or 0 VO = VDD or 0 VI = VDD or 0, WS74HC245 MIN 2V VI = VIH or VIL DIR or OE TA = 25°C TYP MAX 4.5 V IOL = 6 mA IOL = 7.8 mA II IOZ MIN IOH = –20 µA A VI = VIH or VIL VOL VDD C IO = 0 DIR or OE 6V 2 V to 6 V 3 V V AC ELECTRICAL CHARACTERISTICS 3 OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS WS74HC245 switching characteristics over recommended operating free-air temperature range, CL = 50 pF (unless otherwise noted) (see Figure 1) TA = 25°C TYP MAX WS74HC245 PARAMETER FROM (INPUT) TO (OUTPUT) VDD 2V 40 105 130 tpd A or B B or A 4.5 V 15 21 26 6V 12 18 22 ten OE tdis OE tt A or B A or B A or B MIN MIN MAX 2V 125 230 290 4.5 V 23 46 58 6V 20 39 49 2V 74 200 250 4.5 V 25 40 50 6V 21 34 43 2V 20 60 75 4.5 V 8 12 15 6V 6 10 13 UNIT ns ns ns ns switching characteristics over recommended operating free-air temperature range, CL = 150 pF (unless otherwise noted) (see Figure 1) TA = 25°C MIN TYP MAX WS74HC245 PARAMETER FROM (INPUT) TO (OUTPUT) VDD 2V 54 135 170 tpd A or B B or A 4.5 V 18 27 34 ten tt OE A or B A or B MIN MAX 6V 15 23 29 2V 150 270 335 4.5 V 31 54 67 6V 25 46 56 2V 45 210 265 4.5 V 17 42 53 6V 13 36 45 UNIT ns ns ns operating characteristics, TA = 25°C PARAMETER Cpd 4 Power dissipation capacitance per transceiver TEST CONDITIONS No load TYP 40 UNIT pF OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS WS74HC245 PARAMETER MEASUREMENT INFORMATION VCC PARAMETER Test Point From Output Under Test tPZH S1 ten RL CL (see Note A) 1 kΩ tPZL tPHZ tdis S2 RL tPLZ tpd or tt 1 kΩ –– LOAD CIRCUIT CL S1 S2 50 pF or 150 pF Open Closed Closed Open Open Closed Closed Open Open Open 50 pF 50 pF or 150 pF VDD Input 50% 50% 0V tPLH In-Phase Output 50% 10% tPHL 90% VOH 50% 10% V OL tf 90% tr tPHL Out-of-Phase Output 90% tPLH 50% 10% 50% 10% 90% VOH VOL tf tr VOLTAGE WAVEFORMS PROPAGATION DELAY AND OUTPUT TRANSITION TIMES Output Control (Low-Level Enabling) VDD 50% 50% 0V tPZL Output Waveform 1 (See Note B) tPLZ 10% tPZH Input 50% 10% 90% 90% tr VDD 50% 10% 0 V Output Waveform 2 (See Note B) ≈VDD ≈VCC 50% VOL tPHZ 50% 90% VOH ≈0 V tf VOLTAGE WAVEFORM INPUT RISE AND FALL TIMES VOLTAGE WAVEFORMS ENABLE AND DISABLE TIMES FOR 3-STATE OUTPUTS NOTES: A. CL includes probe and test-fixture capacitance. B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control. Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control. C. Phase relationships between waveforms were chosen arbitrarily. All input pulses are supplied by generators having the following characteristics: PRR ≤ 1 MHz, ZO = 50 Ω, tr = 6 ns, tf = 6 ns. D. The outputs are measured one at a time with one input transition per measurement. E. tPLZ and tPHZ are the same as tdis. F. tPZL and tPZH are the same as ten. G. tPLH and tPHL are the same as tpd. Figure 1. Load Circuit and Voltage Waveforms 5 OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS WS74HC245 PIN DESCRIPTION PIN NO. SYMBOL 1 2, 3, 4, 5, 6, 7, 8, 9 10 18, 17, 16, 15, 14, 13, 12, 11 19 20 DIR A1 – A8 VSS B1 – B8 OE VDD Direction control Data inputs / Outputs Ground (0V) Data inputs / Outputs Output enable input (active Low) Positive power supply PAD DIAGRAM B7 VSS B8 A8 A7 B6 A6 B5 WS74 HC245 Die Size = 69 mil x 72 mil A5 Pad size = 90 um x 90 um B4 A4 B3 A3 B2 B1 OE VDD DIR A1 A2 The Coordinate of Low Left Corner for Each Pad B2 (-741.9, -722.4) A3 ( 651.8, -503.2) B8 (-267.8, 657.6) B1 (-558.3, -747.1) A4 ( 651.8, -124.2) B7 (-466.6, 657.6) OE (-288.0, -747.1) A5 ( 651.8, 74.6) B6 (-741.9, 506.6) VDD(-111.4, -742.5) A6 ( 651.8, 454.0) B5 (-741.9, 236.8) DIR ( 85.8, -747.1) A7 ( 559.5, 657.6) B4 (-741.9, -143.4) A1 ( 262.6, -747.1) A8 ( 179.3, 657.6) B3 (-741.9, -342.2) A2 ( 642.8, -747.1) VSS ( 2.7, 658.6) 6 WS74HC245 OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS 7 WS74HC245 8 OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS