1 Features

? AEC-Q100 qualified for automotive applications:

– Temperature grade 1: –40°C to +125°C, TA

? Functional Safety-Capable

– Documentation available to aid functional safety

system design

? Very-low power consumption

– 1mW (typical) at VDD = 5V

? Astable operation up to 3MHz

? CMOS output capable of swinging rail to rail

? High-output-current capability

– Sink 200mA

– Source 50mA

? Output fully compatible with CMOS, TTL, and

MOS logic

? Integrated RESET pullup to VDD

? Power-on reset to known state

? Integrated thermal shutdown protection

? Single-supply operation from 1.5V to 18V

2 Applications

? Automotive lighting

? Vehicle instrument cluster

? Telematics

? Pulse generation

? Sequential timing

? Time delay generation

? Pulse width modulation

? Pulse position modulation

? MOSFET gate drive

3 Description

The TLC3555-Q1 is a monolithic timing circuit

fabricated using a TI CMOS process. The timer is

fully compatible with CMOS, TTL, and MOS logic

and operates at frequencies to 3MHz and even

beyond. The TLC3555-Q1 improves upon the existing

TLC555-Q1 from both a performance and feature

standpoint, with tighter specification tolerances and

additional features, such as thermal shutdown and

power-on reset.

The trigger, threshold, and reset logic of the TLC3555-

Q1 follow the same truth table as the TLC555-Q1. Set

the reset pin (RESET) high for typical operation, or

set the reset pin low to reset the flip-flop and force

the output low. The TLC3555-Q1 features an internal

pullup resistor from RESET to VDD, which can reduce

passive count and save board area.

As a result of low propagation delay and rapid

rise and fall times, the TLC3555-Q1 supports higherfrequency

astable operation than previous timers such

as the NE555 and TLC555-Q1. At a 15V supply,

the TLC3555-Q1 achieves a clean square wave at

3.1MHz in TI's conventional astable test circuit. When

used as an oscillator, with the output and inputs

tied together, the TLC3555-Q1 achieves an oscillatory

frequency of 7.2MHz. Circuit parasitics dominate the

response at high frequencies. In addition to the

D package, which is pin-to-pin compatible with the

TLC555-Q1, the TLC3555-Q1 is offered in a DDF

package that enables concise implementations with

reduced parasitics.