STMicroelectronics TS555IDTTR

Overview

TS555IDTTR from STMicroelectronics is a low-power single CMOS timer IC designed for precision timing in battery-powered and space-constrained systems. It delivers 110 µA typical supply current at 5 V, supports 2.7 MHz maximum astable frequency, operates across 2–16 V supply range, and maintains timing accuracy in both monostable and astable modes - used in portable instrumentation, sensor wake-up circuits, and LED flash controllers.

For engineers reviewing the TS555IDTTR datasheet, TS555IDTTR pinout, TS555IDTTR application, or TS555IDTTR equivalent, key selection criteria include ultra-low ICC (90 µA @ 3 V), high input impedance (10¹² Ω), reduced supply current spikes during transitions, and SO8 package compatibility with legacy NE555 layouts while enabling smaller decoupling capacitors.

Technical Context

The TS555 implements a CMOS-based relaxation oscillator architecture with dual comparators, SR flip-flop, and discharge transistor - identical functional topology to bipolar 555 timers but with rail-to-rail input stages and CMOS output stage. Its threshold and trigger comparators reference internal voltage dividers (1/3 VCC and 2/3 VCC), ensuring supply-independent timing intervals in both monostable (t = 1.1·R·C) and astable (f = 1.44/[(RA + 2RB)·C]) configurations.

Unlike bipolar NE555, it eliminates large supply current transients during output switching via optimized internal drive logic, reducing required decoupling capacitance. High-impedance inputs (10¹² Ω) minimize loading on timing capacitors, enabling use of sub-nF values without drift - critical for compact, low-power designs operating from 2 V to 16 V over –40 °C to +125 °C.

Key Specifications

Pinout & Package

TS555IDTTR is housed in an SO8 (plastic micropackage) with 1.27 mm pitch, compliant with ECOPACK environmental standards. The package measures 4.90 mm × 6.00 mm × 1.75 mm (L × W × H) and features gull-wing leads suitable for reflow soldering.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar timer IC applications.

Compared with NE555P and TLC555CP, TS555IDTTR uniquely combines ultra-low ICC (90 µA @ 3 V), full automotive temperature range (–40 °C to +125 °C), and 2.7 MHz capability - making it the only option qualified for long-life, wide-voltage, thermally demanding embedded timing.

Availability

TS555IDTTR is available at Aetrix Electronics and suitable for portable medical sensors, industrial motor control, smart lighting systems, and automotive body electronics requiring stable component supply across extended temperature and voltage ranges.

Supply support for TS555IDTTR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, sensors, and analog components for industrial, automotive, and consumer markets.

The TS555 belongs to ST's precision analog timer product line, engineered specifically for low-power, high-accuracy timing in harsh environments - targeting applications where battery longevity, thermal resilience, and supply voltage flexibility are critical design constraints.

FAQ

What is the minimum supply voltage for reliable TS555IDTTR operation?

The TS555IDTTR operates reliably down to 2 V per its specified operating conditions (Table 2). At this voltage, supply current drops to 65 µA typ, and timing accuracy remains within ±4% in monostable mode. Internal comparators retain proper hysteresis and output stage functionality, validated across –40 °C to +125 °C.

Can TS555IDTTR replace NE555 in existing PCB layouts?

Yes - TS555IDTTR uses the same SO8 package and pinout as standard NE555 variants, with identical terminal functions (GND, Trigger, Output, Reset, Control Voltage, Threshold, Discharge, VCC). No layout changes are needed, though decoupling capacitors may be reduced due to lower supply current spikes.

Does TS555IDTTR support adjustable duty cycle in astable mode?

Yes - by configuring external resistors RA and RB (with RA between VCC and Discharge, RB between Discharge and Threshold/Trigger), the duty cycle is precisely set as D = RB/(RA + 2RB). This enables ratios from near 0% to near 100%, confirmed in Figure 6 and Table 8 for VCC = 5 V and C = 0.1 µF.

What is the maximum continuous output current capability?

The TS555IDTTR output stage supports ±100 mA peak sink/source current per Absolute Maximum Ratings (Table 1), with VOL = 0.6 V max at 8 mA sink and VOH = 4.4 V min at 2 mA source under 5 V supply. Sustained DC current should remain ≤50 mA to maintain thermal stability within SO8 package limits.