PRECISION SINGLE CELL TIMER ZSCT1555 ISSUE 3 - JULY 2006 and the output goes low. The reset pin has DEVICE DESCRIPTION priority over all the other inputs and is used These devices are precision timing circuits for to start new timing cycles. A low on the reset generation of accurate time delays or input causes the flip-flop to reset forcing the oscillation. Advanced circuit design means that output low. Whenever the output is forced these devices can operate from a single battery low then the internal discharge transistor is cell with the minimum of quiescent current. turned on. In monostable mode time delays are FEATURES controlled by a single resistor and capacitor network. In astable mode the frequency and 0.9V supply operating voltage guaranteed duty cycle can be accurately and Pin connections comparable with 555 independently controlled with two external series timers resistors and one capacitor. Very low quiescent current 74 A The threshold and trigger levels are normally SO8 and DIL8 packages set as a proportion of V by internal resistors. CC Operating temperature range These levels can be programmed by the use compatible with battery technologies of the control input pin. When the trigger input reduces to a value APPLICATIONS below the trigger level, the flip-flop is set and Portable and battery powered the output goes high. With the trigger input equipment above the trigger level and the threshold input Low voltage and low power systems above the threshold level, the flip-flop is reset SCHEMATIC DIAGRAM 8 VCC CONTROL 5 6 THRESH 2 TRIGGER 7 DISCHARGE 3 OUTPUT 4 RESET 1 GND Issue 3 - July 2006 Zetex Semiconductors plc 2006ZSCT1555 ABSOLUTE MAXIMUM RATINGS Supply Voltage 9V Power Dissipation (Tamb=25C) Input Voltages 9V DIL8 625mW (Cont, Reset, Thres, Trig) SO8 625mW Output Current 100mA Recommended Operating Conditions Operating Temperature -20 to 100C Supply Voltage 0.9V(min) 6V(max) Storage Temperature -55 to 150C Input Voltages 6V(max) (Cont, Reset, Thres, Trig) Output Current Sink 100mA(max) Source 150A(max) ELECTRICAL CHARACTERISTICS TEST CONDITIONS (Unless otherwise stated):T = 25C,V = 1.5V amb CC SYMBOL PARAMETER CONDITIONS LIMITS UNITS MIN. TYP. MAX. V Supply Voltage 0.9 6 V CC I Supply Current no load 74 120 A CC V = 5V, no load 150 200 CC V Threshold Voltage 1.195 1.22 1.245 V TH V = 5V 3.9 4 4.1 CC I Threshold Current (Note 1) 0 20 100 nA TH V Trigger Voltage 0.2 0.25 0.3 V TR V = 5V 0.57 0.62 0.67 CC I Trigger Current 0 -35 -100 nA TR t Trigger Propagation delay Delay from trigger 2 s PD to output V Reset Voltage 0.1 0.2 0.4 V RS I Reset Current Reset 0V 0 -5 -10 A RS I Discharge switch Off-state 0 10 100 nA DS current V Discharge switch On-state I = 0.2mA 0 180 225 mV DS DS voltage V = 5V, I = 0.3mA 0 240 350 CC DS V Control Voltage (Open Circuit) 1.195 1.22 1.245 V CT V = 5V 3.9 4 4.1 CC V Output Voltage (Low) I =10mA 0 0.15 0.3 V OL OL I =50mA 0 0.45 0.65 OL V =5V, I =10mA 0 0.13 0.3 CC OL V =5V, I =100mA 0 0.65 1 CC OL V Output Voltage (High) I = 100A 1 1.1 1.5 V OH OH 4.5 4.6 5 V = 5V, I = 150A CC OH Issue 3 - July 2006 www.zetex.com Zetex Semiconductors plc 2006