STMicroelectronics TS556IDTTR

Overview

TS556IDTTR from STMicroelectronics is a dual CMOS timer IC designed for precision timing in monostable and astable configurations. It delivers 220 µA typical supply current at 5 V, supports up to 2.7 MHz astable frequency, operates across 2–16 V supply, and features 10¹² Ω input impedance-enabling low-power sensor interface and battery-operated timing circuits.

For engineers reviewing the TS556IDTTR datasheet, TS556IDTTR pinout, TS556IDTTR application, or TS556IDTTR equivalent, key selection criteria include supply current vs. voltage (180–340 µA typ. from 3–12 V), timing accuracy (±2% monostable, ±3% astable), discharge saturation voltage (0.2–0.35 V at 10 mA), output drive capability (±100 mA), and SO14 thermal resistance (105 °C/W).

Technical Context

The TS556 integrates two independent CMOS-based 555-style timers sharing a common supply and ground. Each timer uses high-impedance comparators (10¹² Ω) and a precision resistive divider (1/3 and 2/3 VCC thresholds) to achieve supply-independent timing intervals. Internal logic ensures reset dominance over trigger and maintains state integrity during supply transients.

Its dual architecture enables synchronized or isolated timing functions-e.g., one section as a precision delay generator and the other as a variable-duty-cycle oscillator-with no cross-coupling between sections. Output transitions are slew-rate controlled to minimize supply current spikes, reducing required decoupling capacitance versus bipolar NE556.

Key Specifications

Pinout & Package

TS556IDTTR is housed in a 14-lead SOIC (SO14) package with 1.27 mm pitch, 8.75 mm × 4.0 mm body, and 1.75 mm max height. The package meets ECOPACK2 environmental compliance and supports reflow soldering per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with NE556DR and LM556CN/NOPB, TS556IDTTR offers >96% lower supply current, >27× higher maximum frequency, and integrated ESD protection (1200 V HBM), making it the sole choice for modern portable, automotive, and industrial timing where efficiency and density matter.

Availability

TS556IDTTR is available at Aetrix Electronics and suitable for industrial sequencers, automotive cabin timers, battery-powered sensor wake-up circuits, and LED status indicators requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TS556IDTTR 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 analog, MCU, power, and sensing solutions for automotive, industrial, and consumer markets.

The TS556 belongs to ST's precision analog timer product line, engineered specifically for replacing legacy bipolar 556 timers in space-, power-, and reliability-constrained applications while maintaining pin and functional compatibility.

FAQ

What is the maximum recommended load capacitance for TS556IDTTR outputs?

The TS556IDTTR output drivers are characterized with 10 pF load for rise/fall time specs (25 ns/20 ns), but can safely drive up to 100 pF without oscillation or excessive delay. For loads >100 pF, add a series 10–50 Ω resistor near the output pin to damp ringing and maintain timing integrity in high-speed astable modes.

Can TS556IDTTR operate reliably at 2 V supply with full functionality?

Yes-TS556IDTTR is fully specified down to 2 V: supply current is 130 µA typ., trigger voltage is 0.4 V min, and output swing remains rail-to-rail. However, maximum astable frequency drops to ~100 kHz at 2 V, and output drive strength decreases to ±20 mA, so verify timing and load requirements for each application.

How does the TS556IDTTR handle simultaneous trigger and reset pulses?

Reset has priority over trigger: when both pins 2 (Trigger A) and 4 (Reset A) go low simultaneously, the output is forced LOW and the internal timing capacitor is discharged immediately. This hard reset overrides any pending monostable timeout or astable cycle phase, ensuring deterministic state recovery.

Is the SO14 package of TS556IDTTR compatible with standard 0.156" wide SOIC footprints?

No-the TS556IDTTR uses a narrow-body SO14 (8.75 mm × 4.0 mm) with 1.27 mm lead pitch, matching JEDEC MS-012, not the wider 0.156" (3.96 mm) DIP-14 or wide SOIC. PCB footprints must follow ST's SO14 mechanical data (DocID4078 Rev 4, Table 11), especially D = 8.55–8.75 mm and E = 3.80–4.00 mm.