SN74HC238N

XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer General Description The SN74HC/HCT238 decodes three binary weighted address inputs (A0, A1 and A2) to eight mutually — — exclusive outputs (Y0 to Y7). The device features three enable inputs (E1 and E2 and E3). Every output — — will be LOW unless E1 and E2 are LOW and E3 is HIGH. This multiple enable function allows easy parallel expansion to a 1-of-32 (5 to 32 lines) decoder with just four SN74HC/HCT238 ICs and one inverter. The SN74HC/HCT238 can be used as an eight output demultiplexer by using one of the active LOW enable inputs as the data input and the remaining enable inputs as strobes. Inputs include clamp diodes. This enables the use of current limiting resistors to interface inputs to voltages in excess of VCC . .Features Input levels: For SN74HC238: CMOS level For SN74HCT238: TTL level Demultiplexing capability Multiple input enable for easy expansion Ideal for memory chip select decoding Active HIGH mutually exclusive outputs Specified from -40C to +105C Packaging information: DIP16/SOP16/TSSOP16 Ordering Information 型号 封装 丝印 包装 包装数量 SN74HC238N DIP-16 74HC238N 管装 1000/ 盒 SN74HC238DTR SOP-16 74HC238 编带 2500/ 盘 SN74HC238TDTR TSSOP-16 74HC238 编带 编带 3000/ 盘 SN74HCT238DTR SN74HCT238TDTR XBLWversion1.0 SOP-16 TSSOP-16 74HCT238 74HCT238 编带 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 2500/ 盘 3000/ 盘 第 1 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer 2 Block Diagram And Pin Description 2.1 Block Diagram Figure 1. Logic symbol Figure 2. Functional diagram Figure 3. Logic diagram XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 2 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer 2.2 Pin Configurations 2.3 Pin Description Description address input address input address input Pin No. 1 2 3 Pin Name A0 A1 4 E1 — enable input (active LOW) 5 — E2 enable input (active LOW) 6 7 8 9 10 E3 Y7 GND Y6 Y5 11 12 13 14 15 16 Y4 Y3 enable input (active HIGH) output (active HIGH) ground (0V) output (active HIGH) output (active HIGH) output (active HIGH) output (active HIGH) A2 Y2 Y1 Y0 output (active HIGH) output (active HIGH) output (active HIGH) supply voltage VCC 2.4 Function Table Input — E1 — E2 E3 A0 Output A1 A2 Y2 Y3 Y4 Y5 Y6 Y7 H X X X X X L L L X H X X X X L L L X X L X X X L L L L L H L L L H L L L L H H L L L H L L L H L H L L L H L L H H H L L L L L L H L L H L L L L L H H L H L L L L L H L H H L L L L L H H H H L L L Note: H=HIGH voltage level; L=LOW voltage level; X=don’t care. L L L L L L H L L L L L L L L L L L H L L L L L L L L L L L H L L L L L L L L L L L H L L L L L L L L L L L H XBLWversion1.0 Y0 Y1 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 3 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer 3 Electrical Parameter 3.1 Absolute Maximum Ratings Parameter supply voltage input clamping current output clamping current output current supply current ground current storage temperature total power dissipation Soldering temperature Symbol VCC Conditions - Min. -0.5 Max. +7.0 Unit V IIK VI < -0.5V or VI > VCC+0.5V - ±20 mA IOK VO < -0.5V or VO > VCC+0.5V - ±20 mA IO ICC IGND -0.5V < VO < VCC+0.5V - -50 ±25 +50 - mA mA mA Tstg - -65 +150 C Ptot - - 500 mW DIP SOP 10s TL 245 250 C C (Voltages are referenced to GND(ground=0V), unless otherwise specified.) Note: [1] For DIP16 packages: above 70C the value of Ptot derates linearly with 12mW/K. [2] For SOP16 packages: above 70C the value of Ptot derates linearly with 8mW/K. [3] For (T)SSOP16 packages: above 60C the value of Ptot derates linearly with 5.5mW/K. 3.2 Recommended Operating Conditions Parameter Symbol supply voltage input voltage output voltage VCC VI VO input transition rise and fall rate Δt/ΔV ambient temperature Tamb supply voltage input voltage output voltage input transition rise and fall rate ambient temperature XBLWversion1.0 Min. Typ. Max. Unit VCC=2.0V VCC=4.5V VCC=6.0V 2.0 0 0 5.0 V V V - 6.0 VCC VCC 625 139 83 ns/V ns/V ns/V - -40 - +105 C - 4.5 0 0 5.0 - 5.5 VCC VCC V V V Δt/ΔV VCC=4.5V - 1.67 139 ns/V Tamb - -40 - +105 C Conditions SN74HC238 SN74HCT238 VCC VI VO - 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 1.67 第 4 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer 3.3 Electrical Characteristics 3.3.1 DC Characteristics 1 (Tamb=25C, voltages are referenced to GND (ground=0V), unless otherwise specified.) Parameter Symbol HIGH-level input voltage VIH LOW-level input voltage VIL HIGH-level output voltage LOW-level output voltage input leakage current supply current input capacitance HIGH-level input voltage LOW-level input voltage Conditions SN74HC238 VCC=2.0V VCC=4.5V VCC=6.0V VCC=2.0V VCC=4.5V VCC=6.0V IO=-20uA; VCC=2.0V IO=-20uA; VCC=4.5V VI = VIH or VIL IO=-20uA; VCC=6.0V IO=-4.0mA; VCC=4.5V IO=-5.2mA; VCC=6.0V IO=20uA; VCC=2.0V IO=20uA; VCC=4.5V IO=20uA; VCC=6.0V VI = VIH or VIL IO=4.0mA; VCC=4.5V IO=5.2mA; VCC=6.0V Min. Typ. Max. Unit 1.5 3.15 4.2 0.5 1.35 1.8 - 1.2 2.4 3.2 0.8 2.1 2.8 2.0 4.5 6.0 4.32 5.81 0 0 0 0.15 0.16 0.1 0.1 0.1 0.26 0.26 V V V V V V V V V V V V V V V V II VI=VCC or GND; VCC=6.0V - - ±0.1 uA ICC VI=VCC or GND; IO=0A; VCC=6.0V - - 8.0 uA CI - - 3.5 - pF V OH VOL SN74HCT238 VIH VCC=4.5V to 5.5V 2.0 1.6 - V VIL VCC=4.5V to 5.5V - 1.2 0.8 V 4.4 3.98 - 4.5 4.32 0 0.16 0.1 0.26 V V V V - - ±0.1 uA - 70 40 8.0 252 144 uA uA uA - 145 522 uA - 3.5 - pF HIGH-level output voltage V OH VI = VIH or VIL ; VCC=4.5V LOW-level output voltage input leakage current supply current VOL VI = VIH or VIL ; VCC=4.5V additional supply current ΔICC input capacitance CI XBLWversion1.0 1.9 4.4 5.9 3.98 5.48 II ICC IO=-20uA IO=-4.0mA IO=20uA IO=4.0mA VI=VCC or GND; VCC=5.5V VI=VCC or GND; IO=0A; VCC=5.5V VI=VCC-2.1V; An inputs — — other inputs at VCC E1, E2 inputs or GND; IO=0A; E3 input VCC=4.5V to 5.5V - 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 5 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer 3.3.2 DC Characteristics 2 (Tamb=-40C to +85C, voltages are referenced to GND (ground=0V), unless otherwise specified.) Parameter Symbol Conditions SN74HC238 VCC=2.0V VCC=4.5V VCC=6.0V VCC=2.0V VCC=4.5V VCC=6.0V IO=-20uA; VCC=2.0V IO=-20uA; VCC=4.5V VI = VIH or VIL IO=-20uA; VCC=6.0V IO=-4.0mA; VCC=4.5V IO=-5.2mA; VCC=6.0V IO=20uA; VCC=2.0V IO=20uA; VCC=4.5V IO=20uA; VCC=6.0V VI = VIH or VIL IO=4.0mA; VCC=4.5V IO=5.2mA; VCC=6.0V Min. Typ. Max. Unit 1.5 3.15 4.2 0.5 1.35 1.8 - - 0.1 0.1 0.1 0.33 0.33 V V V V V V V V V V V V V V V V II VI=VCC or GND; VCC=6.0V - - ±1.0 uA ICC VI=VCC or GND; IO=0A; VCC=6.0V SN74HCT238 - - 80 uA VIH VCC=4.5V to 5.5V 2.0 - - V VIL VCC=4.5V to 5.5V - - 0.8 V 4.4 3.84 - - 0.1 0.33 V V V V - - ±1.0 uA - - - - 80 315 180 uA uA uA - - 653 uA HIGH-level input voltage VIH LOW-level input voltage VIL HIGH-level output voltage LOW-level output voltage input leakage current supply current HIGH-level input voltage LOW-level input voltage V OH VOL HIGH-level output voltage V OH VI = VIH or VIL ; VCC=4.5V LOW-level output voltage input leakage current supply current VOL VI = VIH or VIL ; VCC=4.5V additional supply current ΔICC 3.3.4 XBLWversion1.0 IO=-20uA IO=-4.0mA IO=20uA IO=4.0mA VI=VCC or GND; VCC=5.5V II ICC VI=VCC or GND; IO=0A; VCC=5.5V VI=VCC-2.1V; An inputs — — other inputs at VCC E1, E2 inputs or GND; IO=0A; E3 input VCC=4.5V to 5.5V 1.9 4.4 5.9 3.84 5.34 AC Characteristics 1 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 6 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer (Tamb=25C, voltages are referenced to GND (ground=0V), unless otherwise specified.) Symbol Parameter propagation delay tpd Conditions SN74HC238 VCC=2.0V VCC=4.5V An to Yn; VCC=5.0V; CL=15pF see Figure 5 VCC=6.0V VCC=2.0V VCC=4.5V E3 to Yn; VCC=5.0V; CL=15pF see Figure 5 VCC=6.0V VCC=2.0V — VCC=4.5V En to Yn; VCC=5.0V; CL=15pF see Figure 6 VCC=6.0V VCC=2.0V see Figure 5, 6 VCC=4.5V VCC=6.0V Min. Typ. Max. Unit - 47 17 14 14 52 19 16 15 50 18 17 14 19 7 6 150 30 26 75 15 13 ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns 26 160 32 27 155 31 transition time tt power dissipation capacitance CPD per package; VI=GND to VCC - 72 - pF tpd transition time power dissipation capacitance tt - 19 18 20 20 20 21 7 35 propagation delay SN74HCT238 VCC=4.5V An to Yn; VCC=5.0V; CL=15pF see Figure 5 VCC=4.5V E3 to Yn; VCC=5.0V; CL=15pF see Figure 5 — VCC=4.5V En to Yn; VCC=5.0V; CL=15pF see Figure 6 VCC=4.5V; see Figure 5, 6 15 ns ns ns ns ns ns ns CPD per package; VI=GND to VCC- 1.5V - 76 - pF 37 35 Note: [1] tpd is the same as tPLH and tPHL. [2] tt is the same as tTHL and tTLH . [3] CPD is used to determine the dynamic power dissipation (PD in uW). PD=CPD ×VCC2 ×fi ×N+∑(CL ×VCC2 ×fo) where: fi=input frequency in MHz; fo=output frequency in MHz; CL=output load capacitance in pF; VCC=supply voltage in V; N=number of inputs switching; ∑(CL ×VCC2 ×fo)=sum ofoutputs. XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 7 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer 3.3.5 AC Characteristics 2 (Tamb=-40C to +85C, voltages are referenced to GND (ground=0V), unless otherwise specified.) Symbol Parameter propagation delay tpd transition time tt propagation delay tpd Conditions SN74HC238 VCC=2.0V An to Yn; VCC=4.5V see Figure 5 VCC=6.0V VCC=2.0V E3 to Yn; VCC=4.5V see Figure 5 VCC=6.0V VCC=2.0V — En to Yn; VCC=4.5V see Figure 6 VCC=6.0V VCC=2.0V see Figure 5, 6 VCC=4.5V VCC=6.0V SN74HCT238 An to Yn; VCC=4.5V see Figure 5 E3 to Yn; VCC=4.5V see Figure 5 Min. Typ. Max. Unit - - 190 38 33 200 40 34 195 39 33 95 19 16 ns ns ns ns ns ns ns ns ns ns ns ns - - 44 ns - - 46 ns - - 44 ns - - 19 ns — tt transition time En to Yn; VCC=4.5V see Figure 6 VCC=4.5V; see Figure 5, 6 Note: [1] tpd is the same as tPLH and tPHL. [2] tt is the same as tTHL and tTLH . XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 8 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer 3.3.6 AC Characteristics 3 (Tamb=-40C to +105C, voltages are referenced to GND (ground=0V), unless otherwise specified.) Symbol Parameter Conditions Min. Typ. Max. SN74HC238 225 VCC=2.0V An to Yn; 45 VCC=4.5V see Figure 5 38 VCC=6.0V 240 VCC=2.0V propagation E3 to Yn; 48 tpd VCC=4.5V delay see Figure 5 41 VCC=6.0V 235 VCC=2.0V — En to Yn; 47 VCC=4.5V see Figure 6 40 VCC=6.0V 110 VCC=2.0V see Figure 5, 6 22 VCC=4.5V transition time tt 19 VCC=6.0V - propagation delay ns ns ns ns ns ns ns ns ns ns ns ns SN74HCT238 tpd An to Yn; see Figure 5 E3 to Yn; see Figure 5 tt En to Yn; VCC=4.5V see Figure 6 VCC=4.5V; see Figure 5, 6 VCC=4.5V - - 53 ns VCC=4.5V - - 56 ns - - 53 ns - - 22 ns — transition time Unit Note: [1] tpd is the same as tPLH and tPHL. [2] tt is the same as tTHL and tTLH . XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 9 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer 4 Testing Circuit 4 .1 AC Testing Circuit 1 Figure 4. Test circuit for measuring switching times Definitions for test circuit: CL=Load capacitance including jig and probe capacitance. RT=Termination resistance should be equal to the output impedance Zo of the pulse generator. RL=Load resistance. S1=Test selection switch. 4.2 AC Testing Waveform Figure 5. Input (An, E3) to output (Yn) propagation delays and output transition times — — Figure 6. Input (E1, E2) to output (Yn) propagation delays and output transition times XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 10 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer 4.3 Measurement Points Type SN74HC238 SN74HCT238 Input VM 0.5×VCC 1.3V 4.4 Test Data Type SN74HC238 SN74HCT238 5 Package Information Output VM 0.5×VCC 1.3V Input VI VCC 3V VX 0.1×VCC 0.1×VCC S1 position Load tr , tf 6ns 6ns CL 15pF, 50pF 15pF, 50pF VY 0.9×VCC 0.9×VCC RL 1kΩ 1kΩ tPHL, tPLH open open 5.1 DIP14 XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 11 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer 5.2 SOP16 XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 12 页 共 13 页 XBLW SN74HC/HCT238 3-to-8 Line Decoder/Demultiplexer 5.3 TSSOP16 XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 13 页 共 13 页