DATASHEET ICM7555, ICM7556 FN2867 General Purpose Timers Rev 1.00 June 28, 2016 The ICM7555 and ICM7556 are CMOS RC timers providing Features significantly improved performance over the standard SE/NE 555/556 and 355 timers, while at the same time being • Exact equivalent in most cases for SE/NE 555/556 or direct replacements for those devices in most applications. TLC555/556 Improved parameters include low supply current, wide • Low supply current operating supply voltage range, low Threshold, Trigger and - ICM7555 . 60µA Reset currents, no crowbarring of the supply current during output transitions, higher frequency performance and no - ICM7556 . 120µA requirement to decouple Control Voltage for stable operation. • Extremely low input currents . 20pA Specifically, the ICM7555 and ICM7556 are stable controllers • High speed operation . 1MHz capable of producing accurate time delays or frequencies. The • Guaranteed supply voltage range . 2V to 18V ICM7556 is a dual ICM7555, with the two timers operating independently of each other, sharing only V+ and GND. In the • Temperature stability . 0.005%/°C at +25°C one shot mode, the pulse width of each circuit is precisely • Normal reset function - no crowbarring of supply during controlled by one external resistor and capacitor. For astable output transition operation as an oscillator, the free running frequency and the • Can be used with higher impedance timing elements than duty cycle are both accurately controlled by two external regular 555/556 for longer RC time constants resistors and one capacitor. Unlike the regular bipolar SE/NE 555/556 devices, the Control Voltage terminal need not • Timing from microseconds through hours be decoupled with a capacitor. The circuits are triggered and • Operates in both astable and monostable modes reset on falling (negative) waveforms, and the output inverter • Adjustable duty cycle can source or sink currents large enough to drive TTL loads, or provide minimal offsets to drive CMOS loads. • High output source/sink driver can drive TTL/CMOS • Outputs have very low offsets, HIGH and LOW • Pb-free (RoHS Compliant) Applications • Precision timing • Pulse generation • Sequential timing • Time delay generation • Pulse width modulation • Pulse position modulation • Missing pulse detector Pin Configurations ICM7555ICM7556(8 LD PDIP, SOIC)(14 LD PDIP, CERDIP) TOP VIEW TOP VIEW DISCHARGE1 114 VDDTHRESHOLD1 213 DISCHARGE2GND 18 VDDCONTROL 312 THRESHOLD2TRIGGER 27 DISCHARGEVOLTAGE1RESET1CONTROL411OUTPUT 36 THRESHOLDVOLTAGE2OUTPUT1 510 RESET2RESET 45 CONTROLVOLTAGETRIGGER1 69 OUTPUT2GND 78 TRIGGER2 FN2867 Rev 1.00 Page 1 of 13 June 28, 2016