Toshiba Semiconductor and Storage TC4538BP(N,F)

Overview

TC4538BP(N,F) from Toshiba is a dual precision retriggerable/resettable monostable multivibrator in 16-pin DIP package, operating from 3 V to 18 V, with externally programmable pulse width via RX/CX (e.g., 10 ms ±5% at RX = 100 kΩ, CX = 0.1 μF), and edge-triggered inputs A/B enabling flexible timing control in digital logic systems.

For engineers reviewing the TC4538BP(N,F) datasheet, TC4538BP(N,F) pinout, TC4538BP(N,F) application, or TC4538BP(N,F) equivalent, key selection considerations include its dual independent monostable operation, retriggerability, reset capability, wide supply range, and compatibility with TTL/CMOS logic levels across industrial temperature range.

Technical Context

The TC4538BP(N,F) implements two identical CMOS monostable circuits, each with separate A/B trigger inputs (leading/trailing edge selectable), CD enable/disable control, and complementary Q/Q̅ outputs. Pulse width is fully determined by external RC network-no internal timing elements-enabling precise, user-defined delays from microseconds to seconds.

Each section supports independent retriggering during output pulse generation and asynchronous reset via CD low. Input thresholds scale with VDD (VIH ≈ 0.5×VDD, VIL ≈ 0.33×VDD), ensuring robust noise immunity and interoperability with mixed-voltage logic families.

Key Specifications

Pinout & Package

TC4538BP(N,F) uses a 16-pin plastic DIP package (DIP16-P-300-2.54A), 300 mil width, 2.54 mm pitch, with standard through-hole mounting and 1.00 g typical weight.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar monostable multivibrator applications.

Compared with CD4098BE and 74HC4538N, TC4538BP(N,F) uniquely combines dual retriggerable monostables, full 3–18 V operation, RC-programmable pulse widths from μs to seconds, and industrial temperature support - making it optimal for robust, field-configurable timing in mixed-voltage industrial controls.

Availability

TC4538BP(N,F) is available at Aetrix Electronics and suitable for industrial timer sequencing, encoder debouncing, pulse width modulation gate control, and legacy system glitch suppression requiring stable component supply and long-term lifecycle assurance.

Supply support for TC4538BP(N,F) 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

Toshiba Electronic Devices & Storage Corporation is a Japanese semiconductor manufacturer specializing in power devices, logic ICs, and analog components for industrial, automotive, and consumer applications.

The TC4538BP(N,F) belongs to Toshiba's legacy CMOS logic family designed for reliable, low-power, programmable timing functions in industrial control, instrumentation, and legacy system upgrades.

FAQ

What is the maximum output pulse width achievable with TC4538BP(N,F)?

The TC4538BP(N,F) has no theoretical upper limit on output pulse width-it is fully determined by external RX and CX values. With RX = 1 MΩ and CX = 100 μF, TC4538BP(N,F) achieves ~100 s pulses. Practical limits arise from capacitor leakage, resistor tolerance, and temperature drift; for stable long-duration timing, use low-leakage film capacitors and metal-film resistors. The datasheet confirms operation with CX up to 10 μF and RX up to 1000 kΩ.

Can TC4538BP(N,F) operate reliably at 3.3 V supply?

Yes, TC4538BP(N,F) is fully specified down to 3 V VDD, including VIH/VIL thresholds, propagation delays, and output drive strength. At 3.3 V, VIH ≈ 1.65 V and VIL ≈ 1.1 V per scaling rules, ensuring compatibility with 3.3 V CMOS logic. Static current is ~5 μA, and tPLH/tPHL remain within 760 ns max-making TC4538BP(N,F) suitable for mixed-voltage systems interfacing with modern low-voltage MCUs.

How does the retrigger function work on TC4538BP(N,F) compared to standard monostables?

Unlike non-retriggerable monostables that ignore new triggers during output pulse generation, TC4538BP(N,F) restarts the timing cycle on each valid A/B edge while the output is active. This allows continuous pulse extension-e.g., in motion detection circuits where repeated sensor edges maintain an "active" output until motion ceases. The retrigger behavior is inherent to the internal architecture and requires no external components.

Is TC4538BP(N,F) pin-compatible with TC4538BF?

No-TC4538BP(N,F) uses a 16-pin DIP package (DIP16-P-300-2.54A), while TC4538BF uses SOP16 (SOP16-P-300-1.27A). Though electrically identical and sharing the same pin numbering and function mapping, the physical packages differ in pitch (2.54 mm vs 1.27 mm), body size, and mounting method. PCB layout must match the specific variant; TC4538BP(N,F) is not a drop-in replacement for TC4538BF without board redesign.

What is the pulse width matching specification between the two channels of TC4538BP(N,F)?

The TC4538BP(N,F) guarantees pulse width matching of ±1% between Channel 1 and Channel 2 under identical RX/CX conditions and temperature (Ta = 25°C). This tight matching-verified in the Dynamic Electrical Characteristics table as ΔtwOUT-is achieved via matched internal transistor geometries and shared process characteristics. It enables precise differential timing applications such as balanced dead-time generation or dual-channel synchronization without calibration.