NTE955MC Integrated Circuit CMOS Timing Circuit Description: The NTE955MC is a monolithic timing circuit in an 8–Lead DIP type package fabricated using CMOS process. This timer is fully compatible with CMOS, TTL, and MOS logic and operates at frequencies up to 2MHz. Because of its high impedance, this device uses smaller timing capacitors than those used by the NE555. As a result, more accurate time delays and oscillations are possible. Power consumption is low across the full range of power supply voltage. Like the NE555, the NTE955MC has a trigger level equal to approximately one–third of the supply voltage and a threshold level equal to approximately two–thirds of the supply voltage. These levels can be altered by use of the control voltage terminal (Pin5). When the trigger input (Pin2) falls below the trigger level, the flip–flop is set and the output goes high. If Pin2 is above the trigger level and the threshold input (Pin6) is above the threshold level, the flip–flop is reset and the output is low. The reset input (Pin4) can override all other inputs and can be used to initiate a new timing cycle. If Pin4 is low, the flip–flop is reset and the output is low. Whenever the output is low, a low–impedance path is provided between the discharge terminal (Pin7) and GND. All unused inputs should be tied to an appropriate logic level to prevent false triggering. While the CMOS output is capable of sinking over 100mA and sourcing over 10mA, the NTE955MC exhibits greatly reduced supply–current spikes during output transitions. This minimizes the need for the large decoupling capacitors required by the NE555. Features: D Direct Replacement for 555 Timers D Very Low Power Consumption: 1mW Typ at VDD = 5V D Operates in Both Astable and Monostable Modes D CMOS Output Capable of Swinging Rail to Rail D High Output Current Capability: Sink 100mA Typ Source 10mA Typ D Output Fully Compatible with CMOS, TTL, and MOS D Low Supply Current Reduces Spikes During Output Transitions D Single Supply Operation from 2V to 15V Applications: D Precision Timing D Pulse Generation D Sequential Timing D Time Delay Generation D Pulse Width Modulation D Pulse Position Modulation D Linear Ramp Generator Absolute Maximum Ratings: (TA = +25°C, Note 1 unless otherwise specified) Power Supply Voltage (Note 2), VDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18V Input Voltage Range (Any Input), VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 to VDD Sink Current, Discharge or Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150mA Source Current, Output, IO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15mA Continuous Total Power Dissipation, PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1000mW Derate Above 25°C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8mW/°C Operating Temperature Range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0° to +70°C Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65° to +150°C Lead Temperature (During Soldering, 10sec), TL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +260°C Note 1. 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. Note 2. All voltage values are with respect to network GND. Recommended Operating Conditions: Parameter Supply Voltage Operating Ambient Temperature Range Symbol Test Conditions Min Typ Max Unit VDD 2 – 15 V TA 0 – 70 °C Min Typ Max Unit 0.95 1.33 1.65 V 0.85 – 1.75 V – 10 – pA – 75 – pA 0.4 0.67 0.95 V 0.3 – 1.05 V – 10 – pA – 75 – pA 0.4 1.1 1.5 V 0.3 – 2.0 V – 10 – pA – 75 – pA Electrical Characteristics: (TA = +25°C, VDD = 2V unless otherwise specified) Parameter Threshold Voltage Symbol Test Conditions VTH TA = 0° to +70°C Threshold Current ITH TA = 0° to +70°C Trigger Voltage VT TA = 0° to +70°C Trigger Current IT TA = 0° to +70°C Reset Voltage VR TA = 0° to +70°C Reset Current IR TA = 0° to +70°C Control Voltage (Open Circuit) as a Percentage of Supply Voltage TA = 0° to +70°C Discharge Switch On–State Voltage IOL = 1mA 66.7% TA = 0° to +70°C Discharge Switch Off–State Current TA = 0° to +70°C High–Level Output Voltage VOH IOH = –300µA TA = 0° to +70°C Low–Level Output Voltage VOL IOL = 1mA TA = 0° to +70°C Supply Current IDD Note 3 TA = 0° to +70°C – 0.03 0.2 V – – 0.25 V – 0.1 – nA – 0.5 – nA 1.5 1.9 – V 1.5 – – V – 0.07 0.3 V – – 0.35 V – – 250 µA – – 400 µA Note 3. These values apply for the expected operating configurations in which Pin6 is connected directly to Pin7 or Pin2. Electrical Characteristics: (TA = +25°C, VDD = 5V unless otherwise specified) Parameter Symbol Threshold Voltage VTH Threshold Current ITH Test Conditions TA = 0° to +70°C TA = 0° to +70°C Trigger Voltage VT TA = 0° to +70°C Trigger Current IT TA = 0° to +70°C Reset Voltage VR TA = 0° to +70°C Reset Current IR TA = 0° to +70°C Control Voltage (Open Circuit) as a Percentage of Supply Voltage TA = 0° to +70°C Discharge Switch On–State Voltage IOL = 10mA Discharge Switch Off–State Current TA = 0° to +70°C VOH IOH = –1mA TA = 0° to +70°C Low–Level Output Voltage VOL IOL = 8mA TA = 0° to +70°C IOL = 5mA TA = 0° to +70°C IOL = 3.2mA TA = 0° to +70°C Supply Current IDD Typ Max Unit 2.8 3.3 3.8 V 2.7 – 3.9 V – 10 – pA – 75 – pA 1.36 1.66 1.96 V 1.26 – 2.06 V – 10 – pA – 75 – pA 0.4 1.1 1.5 V 0.3 – 1.8 V – 10 – pA – 75 – pA 66.7% TA = 0° to +70°C High–Level Output Voltage Min Note 3 TA = 0° to +70°C – 0.14 0.5 V – – 0.6 V – 0.1 – nA – 0.5 – nA 4.1 4.8 – V 4.1 – – V – 0.21 0.4 V – – 0.5 V – 0.13 0.3 V – – 0.4 V – 0.08 0.3 V – – 0.35 V – 170 350 µA – – 500 µA Note 3. These values apply for the expected operating configurations in which Pin6 is connected directly to Pin7 or Pin2. Electrical Characteristics: (TA = +25°C, VDD = 15V unless otherwise specified) Parameter Threshold Voltage Symbol Test Conditions VTH TA = 0° to +70°C Threshold Current ITH TA = 0° to +70°C Trigger Voltage VT TA = 0° to +70°C Trigger Current IT TA = 0° to +70°C Reset Voltage VR TA = 0° to +70°C Min Typ Max Unit 9.45 10.0 10.55 V 9.35 – 10.65 V – 10 – pA – 75 – pA 4.65 5.0 5.35 V 4.55 – 5.45 V – 10 – pA – 75 – pA 0.4 1.1 1.5 V 0.3 – 1.8 V Electrical Characteristics (Cont’d): (TA = +25°C, VDD = 15V unless otherwise specified) Parameter Reset Current Symbol Test Conditions IR TA = 0° to +70°C Control Voltage (Open Circuit) as a Percentage of Supply Voltage TA = 0° to +70°C Discharge Switch On–State Voltage IOL = 100mA Discharge Switch Off–State Current TA = 0° to +70°C VOH IOH = –10mA TA = 0° to +70°C IOH = –5mA TA = 0° to +70°C IOH = –1mA TA = 0° to +70°C Low–Level Output Voltage VOL IOL = 100mA TA = 0° to +70°C IOL = 50mA TA = 0° to +70°C IOL = 10mA TA = 0° to +70°C Supply Current IDD Typ Max Unit – 10 – pA – 75 – pA 66.7% TA = 0° to +70°C High–Level Output Voltage Min Note 3 TA = 0° to +70°C – 0.77 1.7 V – – 1.8 V – 0.1 – nA – 0.5 – nA 12.5 14.2 – V 12.5 – – V 13.5 14.6 – V 13.5 – – V 14.2 14.9 – V 14.2 – – V – 1.28 3.2 V – – 3.8 V – 0.63 1.0 V – – 1.3 V – 0.12 0.3 V – – 0.4 V – 360 600 µA – – 800 µA Note 3. These values apply for the expected operating configurations in which Pin6 is connected directly to Pin7 or Pin2. Operating Characteristics: (TA = +25°C, VDD = 5V unless otherwise specified) Parameter Symbol Initial Error of Timing Interval (Note 4) Supply Voltage Sensitivity of Timing Interval Output Pulse Rise Time tr Output Pulse Fall Time tf Maximum Frequency in Astable Mode fmax Test Conditions Min Typ Max VDD = 5V to 15V, CT = 0.1µF, RA = RB = 1kΩ Ω to 100kΩ Ω – 1% 3% – 0.1 0.5 %/V RL = 10MΩ, CL = 10pF – 20 75 ns – 15 60 ns 1.2 2.1 – MHz RA = 470Ω, RB = 200Ω, CT = 200pF Unit Note 4. Timing interval error is defined as the difference between the measured value and the average value of a random sample from each process run. Electrical Characteristics: (TA = +25°C, VDD = 5V unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit Threshold Voltage VTH 2.8 3.3 3.8 V Threshold Current ITH – 10 – pA Trigger Voltage VT 1.36 1.66 1.96 V Trigger Current IT – 10 – pA Reset Voltage VR 0.4 1.1 1.5 V Reset Current IR – 10 – pA Electrical Characteristics (Cont’d): (TA = +25°C, VDD = 5V unless otherwise specified) Parameter Symbol Test Conditions Min Control Voltage (Open Circuit) as a Percentage of Supply Voltage Typ Max Unit 66.7% Discharge Switch On–State Voltage IOL = 10mA – 0.14 0.5 V – 0.1 – nA 4.1 4.8 – V Discharge Switch Off–State Current High–Level Output Voltage VOH IOH = –1mA Low–Level Output Voltage VOL IOL = 8mA – 0.21 0.4 V IOL = 5mA – 0.13 0.3 V IOL = 3.2mA – 0.06 0.3 V Note 3 – 170 350 µA Supply Current IDD Note 3. These values apply for the expected operating configurations in which Pin6 is connected directly to Pin7 or Pin2. Function Table: Threshold Voltage Trigger Voltage Reset Voltage Output Discharge Switch Don’t Care Don’t Care < MIN Low On Don’t Care < MIN > MAX High Off > MAX > MAX > MAX Low On < MIN > MAX > MAX As previously established Note 5. For conditions shown as MIN or MAX, use the appropriate value specified under electrical characteristics. Pin Connection Diagram GND 1 8 VCC Trigger 2 7 Discharge Output 3 6 Threshold Reset 4 8 5 Control Voltage 5 .256 (6.52) Max 1 4 .393 (10.0) Max .300 (7.62) .150 (3.81) .100 (2.54) .070 (1.77) Min .300 (7.62)