ICM7555

Features:

• Exact equivalent in most applications for NE/SE555
• Low supply current: 80mA (typ)
• Extremely low trigger, threshold, and reset currents: 20pA (typ)
• High-speed operation: 500kHz guaranteed
• Wide operating supply voltage range guaranteed 3 to 16V over full automotive temperatures
• Normal reset function; no crowbarring of supply during output transition
• Can be used with higher-impedance timing elements than the bipolar 555 for longer time constants




Application

• Precision timing
• Pulse generation
• Sequential timing
• Time delay generation
• Pulse width modulation
• Pulse position modulation
• Missing pulse detector




Pinout






Specifications

SYMBOL	PARAMETER	RATING	UNITS
VDD	Supply voltage	+18	V
VTRIG1 VCV VTH VRST	Triggerinput voltage Control voltage Threshold input voltage RESETinput voltage	> -0.3 to <VDD + 0.3	V
IOUT	Output current	100	mA
PDMAX	Maximum power dissipation, TA = 25°C (still air)2 N package D package	1160 780	mW mW
TSTG	Storage temperature range	-65 to +150
TSOLD	Lead temperature (Soldering 60s)	300

NOTES:
1. Due to the SCR structure inherent in the CMOS process used to fabricate these devices, connecting any terminal to a voltage greater than V_DD + 0.3V or less than GND -0.3V may cause destructive latch-up. For this reason it is recommended that no inputs from external sources not operating from the same power supply be applied to the device before its power supply is established. In multiple systems, the supply of the ICM7555 must be turned on first.
2. Derate above 25, at the following rates:N package at 9.3mW/ D package at 6.2mW/
3. See "Power Dissipation Considerations" section.




Description

The ICM7555 and ICM7556 are CMOS RC timers providing significantly improved performance over the standard SE/NE555/6 and 355 timers, while at the same time being direct replacements for those devices in most applications. Improved parameters include low supply current, wide operating supply voltage range, low THRESHOLD, TRIGGER and RESET currents, no crowbarring of the supply current during output transitions, higher frequency performance and no requirement to decouple CONTROL VOLTAGE for stable operation. Specifically, the ICM7555 and ICM7556 are stable controllers capable of producing accurate time delays or frequencies. The ICM7556 is a dual ICM7555, with the two timers operating independently of each other, sharing only V+ and GND. In the one shot mode, the pulse width of each circuit is precisely controlled by one external resistor and capacitor. For astable operation as an oscillator, the free running frequency and the duty cycle are both accurately controlled by two external resistors and one capacitor. Unlike the regular bipolar 555/6 devices, the CONTROL VOLTAGE terminal need not be decoupled with a capacitor. The circuits are triggered and reset on falling (negative) waveforms, and the output inverter can source or sink currents large enough to drive TTL loads, or provide minimal offsets to drive CMOS loads.