Datasheet

ManualsBrandsIntersil ManualsClockTimer IC DIL-8

8-170

November 1996

ICM7555, ICM7556

General Purpose Timers

Features

• Exact Equivalent in Most Cases for SE/NE555/556 or

TLC555/556

• Low Supply Current

- ICM7555. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60µA

- ICM7556. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120µA

• Extremely Low Input Currents . . . . . . . . . . . . . . . 20pA

• High Speed Operation . . . . . . . . . . . . . . . . . . . . . . 1MHz

• Guaranteed Supply Voltage Range . . . . . . . 2V to 18V

• Temperature Stability . . . . . . . . . . . . 0.005%/

C at 25

• Normal Reset Function - No Crowbarring of Supply

During Output Transition

• Can be Used with Higher Impedance Timing Elements

than Regular 555/6 for Longer RC Time Constants

• Timing from Microseconds through Hours

• Operates in Both Astable and Monostable Modes

• Adjustable Duty Cycle

• High Output Source/Sink Driver can Drive TTL/CMOS

• Outputs have Very Low Offsets, HI and LO

Applications

• Precision Timing

• Pulse Generation

• Sequential Timing

• Time Delay Generation

• Pulse Width Modulation

• Pulse Position Modulation

• Missing Pulse Detector

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 capa-

ble 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 con-

trolled by two external resistors and one capacitor. Unlike the regu-

lar 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.

Pinouts

Ordering Information

PART NUMBER

(BRAND)

TEMP.

RANGE (

C) PACKAGE

PKG.

NO.

ICM7555CBA

(7555CBA)

0 to 70 8 Ld SOIC M18.5

ICM7555IBA

(7555IBA)

-25 to 85 8 Ld SOIC M18.5

ICM7555IPA -25 to 85 8 Ld PDIP E8.3

ICM7555ITV -25 to 85 8 Pin Metal Can T8.C

ICM7555MTV (Note) -55 to 125 8 Pin Metal Can T8.C

ICM7556IPD -25 to 85 14 Ld PDIP E14.3

ICM7556MJD (Note) -55 to 125 14 Ld CERDIP F14.3

NOTE: Add /883B to part number if 883B processing is desired.

ICM7555 (PDIP, SOIC)

TOP VIEW

ICM7555 (METAL CAN)

TOP VIEW

ICM7556 (PDIP, CERDIP)

TOP VIEW

GND

TRIGGER

OUTPUT

RESET

DISCHARGE

THRESHOLD

CONTROL

VOLTAGE

AND CASE

THRESHOLD

TRIGGER

RESET

GND

OUTPUT

DISCHARGE

CONTROL

VOLTAGE

DISCHARGE

THRESH-

CONTROL

RESET

OUTPUT

TRIGGER

GND

DISCHARGE

THRESHOLD

CONTROL

RESET

OUTPUT

TRIGGER

VOLTAGE

OLD

File Number 2867.2

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

Summary of content (8 pages)

PAGE 1
ICM7555, ICM7556 General Purpose Timers November 1996 Features Description • Exact Equivalent in Most Cases for SE/NE555/556 or TLC555/556 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.
PAGE 2
ICM7555, ICM7556 Absolute Maximum Ratings Thermal Information Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +18V Input Voltage Trigger, Control Voltage, Threshold, Reset (Note 1). . . . . . . . . . . . . . . . . . . . . .V+ +0.3V to GND -0.3V Output Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100mA Thermal Resistance (Typical, Note 2) θJA (oC/W) θJC (oC/W) CERDIP Package . . . . . . . . . . . . . . . .
PAGE 3
ICM7555, ICM7556 Electrical Specifications Applies to ICM7555 and ICM7556, Unless Otherwise Specified (NOTE 4) -55oC TO 125oC TA = 25oC PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX MIN TYP MAX UNITS Discharge Leakage IDIS VDD = 15V - - 10 - - 50 nA Output Voltage VOL VDD = 15V, ISINK = 20mA - 0.4 1.0 - - 1.25 V VDD = 5V, ISINK = 3.2mA - 0.2 0.4 - - 0.5 V VDD = 15V, ISOURCE = 0.8mA 14.3 14.6 - 14.2 - - V VDD = 5V, ISOURCE = 0.8mA 4.0 4.3 - 3.
PAGE 4
ICM7555, ICM7556 Schematic Diagram VDD P P P P R THRESHOLD N N CONTROL VOLTAGE NPN R OUTPUT P P TRIGGER R N N N N N RESET N N GND DISCHARGE R = 100kΩ ±20% (TYP) Application Information General 500 TA = 25oC SUPPLY CURRENT (mA) The ICM7555/6 devices are, in most instances, direct replacements for the NE/SE 555/6 devices. However, it is possible to effect economies in the external component count using the ICM7555/6.
PAGE 5
ICM7555, ICM7556 Power Supply Considerations Monostable Operation Although the supply current consumed by the ICM7555/6 devices is very low, the total system supply current can be high unless the timing components are high impedance. Therefore, use high values for R and low values for C in Figures 2 and 3. In this mode of operation, the timer functions as a one-shot, see Figure 3. Initially the external capacitor (C) is held discharged by a transistor inside the timer.
PAGE 6
ICM7555, ICM7556 1200 MINIMUM PULSE WIDTH (ns) SUPPLY CURRENT (ICM7555) (µA) TA = 25oC 1100 1000 900 800 700 600 500 VDD = 2V 400 300 200 VDD = 5V 100 VDD = 18V 0 200 400 180 360 160 320 140 280 TA = -20oC 120 100 160 TA = 70oC 60 10 20 30 80 20 40 0 0 40 2 4 10 12 14 16 18 20 100 TA = 25oC TA = -20oC OUTPUT SINK CURRENT (mA) OUTPUT SOURCE CURRENT (mA) 8 FIGURE 5. SUPPLY CURRENT vs SUPPLY VOLTAGE -0.1 VDD = 2V -1.0 VDD = 5V -10.0 VDD = 18V -1.0 -0.
PAGE 7
ICM7555, ICM7556 (Continued) 100 8 TA = 25oC DISCHARGE SINK CURRENT (mA) NORMALIZED FREQUENCY DEVIATION (%) Typical Performance Curves 6 4 2 RA = RB = 10MΩ C = 100pF 0 2 RA = RB = 10kΩ C = 0.1µF 4 6 8 0.1 1.0 10.0 TA = 25oC 10.0 VDD = 2V 1.0 0.1 0.01 100.0 0.1 1.0 DISCHARGE LOW VOLTAGE (V) SUPPLY VOLTAGE (V) 600 PROPAGATION DELAY (ns) VDD = 5V 500 400 300 TA = 70oC 200 TA = 25oC TA = -20oC 100 0 0 10 20 30 40 +1.0 RA = RB = 10kΩ C = 0.1µF +0.9 +0.8 +0.7 +0.6 VDD = 5V +0.
PAGE 8
ICM7555, ICM7556 All Intersil semiconductor products are manufactured, assembled and tested under ISO9000 quality systems certification. Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable.