NTE955MC Integrated Circuit CMOS Timing Circuit Description: The NTE955MC is a monolithic timing circuit in an 8Lead 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 con- sumption is low across the full range of power supply voltage. Like the NE555, the NTE955MC has a trigger level equal to approximately onethird of the supply voltage and a threshold level equal to approximately twothirds 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 flipflop 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 flipflop 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 flipflop is reset and the output is low. Whenever the output is low, a lowimpedance path is pro- vided between the discharge terminal (Pin7) and GND. All unused inputs should be tied to an ap- propriate 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 supplycurrent spikes during output transitions. This minimizes the need for the large decoupling capacitors required by the NE555. Features: Direct Replacement for 555 Timers Very Low Power Consumption: 1mW Typ at V = 5V DD Operates in Both Astable and Monostable Modes CMOS Output Capable of Swinging Rail to Rail High Output Current Capability: Sink 100mA Typ Source 10mA Typ Output Fully Compatible with CMOS, TTL, and MOS Low Supply Current Reduces Spikes During Output Transitions Single Supply Operation from 2V to 15V Applications: Precision Timing Pulse Generation Sequential Timing Time Delay Generation Pulse Width Modulation Pulse Position Modulation Linear Ramp GeneratorAbsolute Maximum Ratings: (T = +25C, Note 1 unless otherwise specified) A Power Supply Voltage (Note 2), V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18V DD Input Voltage Range (Any Input), V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 to V I DD Sink Current, Discharge or Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150mA Source Current, Output, I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15mA O Continuous Total Power Dissipation, P . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1000mW D Derate Above 25C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8mW/C Operating Temperature Range, T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to +70C A Storage Temperature Range, T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 to +150C stg Lead Temperature (During Soldering, 10sec), T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +260C L 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 absolutemaximumrated conditions for extended periods may affect device reliability. Note 2. All voltage values are with respect to network GND. Recommended Operating Conditions: Parameter Symbol Test Conditions Min Typ Max Unit Supply Voltage V 2 15 V DD Operating Ambient Temperature Range T 0 70 C A Electrical Characteristics: (T = +25C, V = 2V unless otherwise specified) A DD Parameter Symbol Test Conditions Min Typ Max Unit Threshold Voltage V 0.95 1.33 1.65 V TH T = 0 to +70C 0.85 1.75 V A Threshold Current I 10 pA TH T = 0 to +70C 75 pA A Trigger Voltage V 0.4 0.67 0.95 V T T = 0 to +70C 0.3 1.05 V A Trigger Current I 10 pA T T = 0 to +70C 75 pA A Reset Voltage V 0.4 1.1 1.5 V R T = 0 to +70C 0.3 2.0 V A Reset Current I 10 pA R T = 0 to +70C 75 pA A Control Voltage (Open Circuit) as a T = 0 to +70C 66.7% A Percentage of Supply Voltage Discharge Switch OnState Voltage I = 1mA 0.03 0.2 V OL T = 0 to +70C 0.25 V A Discharge Switch OffState Current 0.1 nA T = 0 to +70C 0.5 nA A HighLevel Output Voltage V I = 300 A 1.5 1.9 V OH OH T = 0 to +70C 1.5 V A LowLevel Output Voltage V I = 1mA 0.07 0.3 V OL OL T = 0 to +70C 0.35 V A Supply Current I Note 3 250 A DD T = 0 to +70C 400 A A Note 3. These values apply for the expected operating configurations in which Pin6 is connected directly to Pin7 or Pin2.