Custom Silicon Solutions, Inc. ©2009

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Version 1.1, May 2009

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Custom Silicon Solutions, Inc.

CSS555C

Micropower Timer (with Internal Timing Capacitor)

GENERAL PART DESCRIPTION

The CSS555C is a micropower version of the popular 555 timer IC. It features an operating current

under 5µA and a minimum supply voltage of 1.2V, making it ideal for battery-operated applications. A

six-decade programmable counter is included to allow generation of long timing delays. Configuration

data for the counter is held in EEPROM to maintain the standard pin count of eight. The analog circuits

are temperature compensated to provide excellent stability over a wide ambient temperature range. A

simple four-wire interface provides Read/Write access to the EEPROM. The CSS555C device includes

an internal precision timing capacitor (CTI). Its value is trimmed to 100pF ±1%.

Key Features

Pin Configuration

• Lowest power 555 timer (by > 10X)!

Active mode current < 5 µA

• Wide operating range

Wide supply range: 1.2V to 5.5V

Temperature range: -40°C to +85°C

• Internal 6 decade, programmable counter

Settings = 1, 10, 10

2, 103, 104, 105 & 106

Multiplies delay time by up to 10

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Figure 1

Delay times from microseconds to days

• Internal 100pF, ±1% Timing Capacitor

Typical Application Circuit

User adjustable, 0.2pF resolution

• Pin-for-pin compatible with 555 series timers

Monostable or Astable operation

• Extremely low transient switching current

“Break-Before-Make” output driver

• Temperature stability – 0.005% per °C

Applications

• Portable & Battery-Powered Systems

Figure 2

• Precision Timing & Pulse Generation

• Ultra Long Period Delay Generation

Ordering Information

• Single Cell Battery Applications

Part Number

Package Description

• Ultra Low Power Timers

CSS555C-ID

8 pin plastic DIP

• Pulse Width Modulation

CSS555C-IS

8 pin plastic SOIC

• Low Cost, High Reliability Applications

See page 9 for more details and options.

Custom Silicon Solutions Inc.

17951 Sky Park Circle, Suite F

Irvine, CA 92614

(949) 797-9220 • FAX: (949) 797-9225 • www.CustomSiliconSolutions.com

GND

TRIGGER

OUTPUT

RESET

V+

DISCHARGE

THRESHOLD

CONTROL V

8

7

6

5

1

2

3

4

PDIP or SOIC

Long Period Delay Generator

VDD

RA

RB

Trigger

Output

Reset

Operating conditions:

RA = RB = 4.7M ,

Internal counter = 10

6 (maximum)

CINT = 100pF, Delay = 16.3 minutes

Average power = 7.5 µW at VDD = 3.0V

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8

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