TC74HC148AP/AF TOSHIBA CMOS Digital Integrated Circuit Silicon Monolithic TC74HC148AP,TC74HC148AF 8-to-3 Line Priority Encoder The TC74HC148A is a high speed CMOS 8-to-3 LINE ENCODER fabricated with silicon gate C2MOS technology. It achieves the high speed operation similar to equivalent LSTTL while maintaining the CMOS low power dissipation. All data inputs and outputs of these encoders are active at the low logic level. The encoder detects a low level of the highest order among eight input signals and outputs the corresponding signal position in binaly code. Enable Input EI and Enable Output EO are used to easily cascade without using external circuits. All inputs are equipped with protection circuits against static discharge or transient excess voltage. TC74HC148AP TC74HC148AF Features • High speed: tpd = 15 ns (typ.) at VCC = 5 V • Low power dissipation: ICC = 4 μA (max) at Ta = 25°C • High noise immunity: VNIH = VNIL = 28% VCC (min) • Output drive capability: 10 LSTTL loads • • Symmetrical output impedance: |IOH| = IOL = 4 mA (min) ∼ tpHL Balanced propagation delays: tpLH − • Wide operating voltage range: VCC (opr) = 2 to 6 V • Pin and function compatible with 74LS148 Weight DIP16-P-300-2.54A SOP16-P-300-1.27A : 1.00 g (typ.) : 0.18 g (typ.) Pin Assignment 1 2007-10-01 TC74HC148AP/AF IEC Logic Symbol Truth Table Inputs E1 0 1 2 3 Outputs 4 5 6 7 A2 A1 A0 GS EO H X X X X X X X X H H H H H L H H H H H H H H H H H H L L X X X X X X X L L L L L H L X X X X X X L H L L H L H L X X X X X L H H L H L L H L X X X X L H H H L H H L H L X X X L H H H H H L L L H L X X L H H H H H H L H L H L X L H H H H H H H H L L H L L H H H H H H H H H H L H X: Don’t care 2 2007-10-01 TC74HC148AP/AF System Diagram Absolute Maximum Ratings (Note 1) Characteristics Symbol Rating Unit Supply voltage range VCC −0.5 to 7 V DC input voltage VIN −0.5 to VCC + 0.5 V DC output voltage VOUT −0.5 to VCC + 0.5 V Input diode current IIK ±20 mA Output diode current IOK ±20 mA DC output current IOUT ±25 mA DC VCC/ground current ICC ±50 mA Power dissipation PD 500 (DIP) (Note 2)/180 (SOP) mW Storage temperature Tstg −65 to 150 °C Note 1: Exceeding any of the absolute maximum ratings, even briefly, lead to deterioration in IC performance or even destruction. Using continuously under heavy loads (e.g. the application of high temperature/current/voltage and the significant change in temperature, etc.) may cause this product to decrease in the reliability significantly even if the operating conditions (i.e. operating temperature/current/voltage, etc.) are within the absolute maximum ratings and the operating ranges. Please design the appropriate reliability upon reviewing the Toshiba Semiconductor Reliability Handbook (“Handling Precautions”/“Derating Concept and Methods”) and individual reliability data (i.e. reliability test report and estimated failure rate, etc). Note 2: 500 mW in the range of Ta = −40 to 65°C. From Ta = 65 to 85°C a derating factor of −10 mW/°C shall be applied until 300 mW. 3 2007-10-01 TC74HC148AP/AF Operating Ranges (Note) Characteristics Symbol Rating Unit Supply voltage VCC 2 to 6 V Input voltage VIN 0 to VCC V VOUT 0 to VCC V −40 to 85 °C Output voltage Operating temperature Topr 0 to 1000 (VCC = 2.0 V) Input rise and fall time 0 to 500 (VCC = 4.5 V) tr, tf ns 0 to 400 (VCC = 6.0 V) Note: The operating ranges must be maintained to ensure the normal operation of the device. Unused inputs must be tied to either VCC or GND. Electrical Characteristics DC Characteristics Characteristics High-level input voltage Low-level input voltage VCC (V) Min Typ. Max Min Max 2.0 1.50 ⎯ ⎯ 1.50 ⎯ 4.5 3.15 ⎯ ⎯ 3.15 ⎯ 6.0 4.20 ⎯ ⎯ 4.20 ⎯ 2.0 ⎯ ⎯ 0.50 ⎯ 0.50 4.5 ⎯ ⎯ 1.35 ⎯ 1.35 6.0 ⎯ ⎯ 1.80 ⎯ 1.80 2.0 1.9 2.0 ⎯ 1.9 ⎯ 4.5 4.4 4.5 ⎯ 4.4 ⎯ 6.0 5.9 6.0 ⎯ 5.9 ⎯ IOH = −4 mA 4.5 4.18 4.31 ⎯ 4.13 ⎯ IOH = −5.2 mA 6.0 5.68 5.80 ⎯ 5.63 ⎯ 2.0 ⎯ 0.0 0.1 ⎯ 0.1 4.5 ⎯ 0.0 0.1 ⎯ 0.1 6.0 ⎯ 0.0 0.1 ⎯ 0.1 IOL = 4 mA 4.5 ⎯ 0.17 0.26 ⎯ 0.33 IOL = 5.2 mA 6.0 ⎯ 0.18 0.26 ⎯ 0.33 ⎯ VIH ⎯ VIL IOH = −20 μA High-level output voltage VOH VIN = VIH or VIL IOL = 20 μA Low-level output voltage VOL Ta = −40 to 85°C Ta = 25°C Test Condition Symbol VIN = VIH or VIL Unit V V V V Input leakage current IIN VIN = VCC or GND 6.0 ⎯ ⎯ ±0.1 ⎯ ±1.0 μA Quiescent supply current ICC VIN = VCC or GND 6.0 ⎯ ⎯ 4.0 ⎯ 40.0 μA 4 2007-10-01 TC74HC148AP/AF AC Characteristics (CL = 15 pF, VCC = 5 V, Ta = 25°C, input: tr = tf = 6 ns) Characteristics Symbol Test Condition Min Typ. Max Unit ⎯ ⎯ 4 8 ns ⎯ ⎯ 15 25 ns ⎯ ⎯ 15 25 ns ⎯ ⎯ 11 19 ns ⎯ ⎯ 11 19 ns ⎯ ⎯ 11 19 ns tTLH Output transition time tTHL Propagation delay time tpLH (IN-A0, A1, A2) tpHL Propagation delay time tpLH (IN-EO, GS) tpHL Propagation delay time tpLH (EI-EO) tpHL Propagation delay time tpLH (EI-GS) tpHL Propagation delay time tpLH (EI-A0, A1, A2) tpHL AC Characteristics (CL = 50 pF, input: tr = tf = 6 ns) Characteristics Output transition time Symbol tTLH tTHL Propagation delay time tpLH (IN-A0, A1, A2) tpHL Propagation delay time tpLH (IN-EO, GS) tpHL Propagation delay time tpLH (EI-EO) tpHL Propagation delay time tpLH (EI-GS) tpHL Propagation delay time tpLH (EI-A0, A1, A2) tpHL Input capacitance CIN Power dissipation capacitance CPD Note: (Note) Ta = −40 to 85°C Ta = 25°C Test Condition Unit VCC (V) Min Typ. Max Min Max 2.0 ⎯ 30 75 ⎯ 95 4.5 ⎯ 8 15 ⎯ 19 6.0 ⎯ 7 13 ⎯ 16 2.0 ⎯ 52 150 ⎯ 190 4.5 ⎯ 19 30 ⎯ 38 6.0 ⎯ 15 26 ⎯ 33 2.0 ⎯ 52 150 ⎯ 190 4.5 ⎯ 19 30 ⎯ 38 6.0 ⎯ 15 26 ⎯ 33 2.0 ⎯ 40 115 ⎯ 145 4.5 ⎯ 14 23 ⎯ 29 6.0 ⎯ 11 20 ⎯ 25 2.0 ⎯ 40 115 ⎯ 145 4.5 ⎯ 14 23 ⎯ 29 6.0 ⎯ 12 20 ⎯ 25 2.0 ⎯ 40 115 ⎯ 145 4.5 ⎯ 14 23 ⎯ 29 6.0 ⎯ 12 20 ⎯ 25 ⎯ ⎯ 5 10 ⎯ 10 pF ⎯ ⎯ 55 ⎯ ⎯ ⎯ pF ⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ns ns ns ns ns ns CPD is defined as the value of the internal equivalent capacitance which is calculated from the operating current consumption without load. Average operating current can be obtained by the equation: ICC (opr) = CPD･VCC･fIN + ICC 5 2007-10-01 TC74HC148AP/AF Typical Application 6 2007-10-01 TC74HC148AP/AF Package Dimensions Weight: 1.00 g (typ.) 7 2007-10-01 TC74HC148AP/AF Package Dimensions Weight: 0.18 g (typ.) 8 2007-10-01 TC74HC148AP/AF RESTRICTIONS ON PRODUCT USE 20070701-EN GENERAL • The information contained herein is subject to change without notice. • TOSHIBA is continually working to improve the quality and reliability of its products. Nevertheless, semiconductor devices in general can malfunction or fail due to their inherent electrical sensitivity and vulnerability to physical stress. It is the responsibility of the buyer, when utilizing TOSHIBA products, to comply with the standards of safety in making a safe design for the entire system, and to avoid situations in which a malfunction or failure of such TOSHIBA products could cause loss of human life, bodily injury or damage to property. In developing your designs, please ensure that TOSHIBA products are used within specified operating ranges as set forth in the most recent TOSHIBA products specifications. Also, please keep in mind the precautions and conditions set forth in the “Handling Guide for Semiconductor Devices,” or “TOSHIBA Semiconductor Reliability Handbook” etc. • The TOSHIBA products listed in this document are intended for usage in general electronics applications (computer, personal equipment, office equipment, measuring equipment, industrial robotics, domestic appliances, etc.).These TOSHIBA products are neither intended nor warranted for usage in equipment that requires extraordinarily high quality and/or reliability or a malfunction or failure of which may cause loss of human life or bodily injury (“Unintended Usage”). Unintended Usage include atomic energy control instruments, airplane or spaceship instruments, transportation instruments, traffic signal instruments, combustion control instruments, medical instruments, all types of safety devices, etc.. Unintended Usage of TOSHIBA products listed in his document shall be made at the customer’s own risk. • The products described in this document shall not be used or embedded to any downstream products of which manufacture, use and/or sale are prohibited under any applicable laws and regulations. • The information contained herein is presented only as a guide for the applications of our products. No responsibility is assumed by TOSHIBA for any infringements of patents or other rights of the third parties which may result from its use. No license is granted by implication or otherwise under any patents or other rights of TOSHIBA or the third parties. • Please contact your sales representative for product-by-product details in this document regarding RoHS compatibility. Please use these products in this document in compliance with all applicable laws and regulations that regulate the inclusion or use of controlled substances. Toshiba assumes no liability for damage or losses occurring as a result of noncompliance with applicable laws and regulations. 9 2007-10-01