Texas Instruments SE555DRG4

Overview

SE555DRG4 from Texas Instruments is a precision bipolar 555 timer IC operating across –55°C to +125°C, supporting monostable and astable timing modes with ±200mA output drive, 4.5V–18V supply range, and 30 ppm/°C temperature coefficient for high-stability industrial and aerospace timing applications.

For engineers reviewing the SE555DRG4 datasheet, SE555DRG4 pinout, SE555DRG4 application, or SE555DRG4 equivalent, this page delivers verified electrical specs, SOIC-8 package details, functional mode behavior, real-world use cases, and two validated alternative parts with documented technical and application differences.

Technical Context

The SE555DRG4 implements a dual-comparator, SR-latch, and high-current output stage architecture. Its internal voltage divider sets fixed trigger (≈⅓ VCC) and threshold (≈⅔ VCC) reference levels, modifiable via the CONT pin. Reset overrides all inputs, forcing low output and enabling discharge switch conduction.

Timing accuracy relies on external RC networks: monostable operation uses one resistor and capacitor for delay control; astable operation uses two resistors and one capacitor to independently adjust frequency and duty cycle. Output rise/fall times are ≤200 ns at 25°C with 15 pF load.

Key Specifications

Pinout & Package

SE555DRG4 is housed in an 8-pin SOIC (D) package with gull-wing leads, 1.27 mm pitch, and JEDEC MS-012AC compliant footprint. Thermal resistance R_θJA = 125.4°C/W enables operation up to 125°C ambient with standard PCB copper.

Key Features

Applications

Equivalent & Alternatives

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

Compared with NE555DR and TLC555CDR, the SE555DRG4 uniquely combines military-grade temperature range, ±200mA drive, and low 30 ppm/°C drift-making it the sole option for high-reliability timing in harsh environments where both thermal robustness and load-driving capability are essential.

Availability

SE555DRG4 is available at Aetrix Electronics and suitable for industrial control timing, pulse-width modulation, missing-pulse detection, and sequential timer chains requiring stable component supply across extreme temperature ranges.

Supply support for SE555DRG4 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

Texas Instruments is a global semiconductor leader delivering analog, embedded processing, and connectivity solutions with emphasis on reliability, longevity, and industrial-grade qualification.

The SE555DRG4 belongs to TI's precision analog timer product line, engineered specifically for mission-critical timing functions in aerospace, defense, and high-reliability industrial systems where extended temperature operation and deterministic behavior are mandatory.

FAQ

What is the maximum supply voltage for the SE555DRG4?

The SE555DRG4 supports a maximum supply voltage of 18V, as specified in its Absolute Maximum Ratings. This exceeds the 16V limit of commercial variants like NE555 and SA555, enabling use with higher-voltage legacy or industrial power rails. Operation at 18V is validated across the full –55°C to +125°C temperature range, and the device maintains specified timing accuracy and output drive performance under this condition. Always include a 0.1 µF ceramic decoupling capacitor close to the VCC and GND pins when operating near maximum voltage.

Can the SE555DRG4 replace a NE555 in an existing design?

The SE555DRG4 is pin-compatible with the NE555 in SOIC-8 (D) and PDIP-8 (P) packages and shares identical pinout and basic functionality. However, due to its wider temperature range (–55°C to +125°C vs. 0°C to +70°C), lower temperature coefficient (30 ppm/°C vs. 150 ppm/°C), and higher output drive (±200mA vs. ±100mA), it may exhibit tighter timing tolerance and greater load capability. Verify timing resistor/capacitor values and thermal dissipation in the target environment before drop-in replacement, especially if operating outside 0°C–70°C.

What is the minimum monostable pulse width achievable with the SE555DRG4?

The SE555DRG4 supports a minimum monostable pulse width of 10 µs, limited by internal comparator storage time when the TRIG pin is grounded. This value holds across the full –55°C to +125°C operating range. Achieving shorter intervals requires external circuitry such as fast comparators or dedicated monostable ICs. For designs requiring sub-10 µs timing, consider evaluating TI's SN74LVC1G123 or similar high-speed retriggerable monostables instead of the SE555DRG4.

How does the CONT pin affect timing accuracy in the SE555DRG4?

The CONT pin on the SE555DRG4 directly sets the internal threshold and trigger reference voltages, allowing external modulation of timing intervals. When left open or bypassed with a capacitor, it defaults to ≈⅔ VCC and ≈⅓ VCC. Applying a stable DC voltage to CONT scales both thresholds proportionally, enabling precise duty-cycle adjustment in astable mode or variable-delay control in monostable mode. Noise on the CONT pin directly impacts timing jitter, so a low-impedance source and local 0.01 µF ceramic bypass are essential for stable operation.

Is the SE555DRG4 RoHS compliant and lead-free?

Yes, the SE555DRG4 is RoHS compliant and lead-free, meeting JEDEC J-STD-020 moisture sensitivity level 3 and TI's corporate environmental standards. The SOIC-8 (D) package uses matte tin lead finish, and the device carries the "G4" suffix per TI's packaging nomenclature, indicating green (halogen-free) and lead-free construction. Full compliance documentation-including test reports and material declarations-is available through TI's Quality & Environmental Information portal using the SE555DRG4 part number.