Vishay Semiconductor Opto Division TSOP75438WTR

Overview

TSOP75438WTR from Vishay Semiconductors is a surface-mount infrared (IR) receiver module optimized for NEC, Sharp, and Mitsubishi remote control protocols at 38 kHz carrier frequency. It integrates a PIN photodiode, preamplifier, AGC-controlled bandpass filter, and demodulator in a single epoxy package with integrated IR filter. It delivers 18 m transmission distance with TSAL6200 emitter and operates from 2.0 V to 5.5 V supply.

For engineers reviewing the TSOP75438WTR datasheet, TSOP75438WTR pinout, TSOP75438WTR application, or TSOP75438WTR equivalent, key selection criteria include AGC4-level noise immunity against fluorescent lamps and Wi-Fi interference, ±75° horizontal directivity, and compatibility with long-burst IR data formats requiring ≥12-cycle gap timing.

Technical Context

The TSOP75438WTR implements an AGC4-configured demodulation architecture tuned specifically for 38 kHz carrier signals, enabling robust rejection of ambient IR noise from LCD TVs and electronic ballasts. Its internal bandpass filter has Δf(3 dB) = f₀/10 and supports envelope duty cycle discrimination up to 5× burst length for reliable signal validation.

It features automatic sensitivity reduction during disturbance events, ensuring spurious output pulses are suppressed without external logic. The device outputs active-low demodulated signals directly compatible with microcontroller GPIO inputs, requiring no additional level-shifting or conditioning circuitry.

Key Specifications

Pinout & Package

TSOP75438WTR uses a 4-pin SMD TSOP package (6.8 mm × 3.0 mm × 2.35 mm) with Heimdall no-lens construction and integrated IR filter. Lead frame assembly includes molded epoxy encapsulation for environmental stability.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar IR receiver applications.

Compared with TSOP75438WTR, TSOP75238W offers broader protocol compatibility at the cost of reduced noise margin, while TSOP38238 replicates core functionality in a non-SMD package-neither is pin-compatible, and both require layout or sourcing adjustments.

Availability

TSOP75438WTR is available at Aetrix Electronics and suitable for consumer electronics remote controls, industrial human-machine interface (HMI) systems, and smart home controller designs requiring stable component supply, consistent AGC4 performance, and long-burst IR protocol support.

Supply support for TSOP75438WTR 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

Vishay Semiconductors is a global manufacturer of discrete semiconductors and passive components, specializing in high-reliability optoelectronics, power management, and sensing solutions.

The TSOP75x series was designed specifically for noise-immune infrared remote control reception in consumer and industrial environments, emphasizing AGC-configurable demodulation, wide operating temperature, and direct microcontroller interfacing.

FAQ

What is the carrier frequency supported by TSOP75438WTR?

The TSOP75438WTR is factory-tuned to 38 kHz carrier frequency, matching industry-standard NEC, Sharp, and Mitsubishi remote control protocols. This frequency is fixed and not adjustable; deviation beyond ±5% of 38 kHz results in significant sensitivity loss per the datasheet's frequency dependence curve (Fig. 5). The device does not support multi-frequency operation or software reconfiguration.

Does TSOP75438WTR require external components for basic operation?

TSOP75438WTR operates with only a 100 nF ceramic decoupling capacitor between VS and GND, as specified in the application circuit. No pull-up resistors, level shifters, or external filters are needed-the demodulated active-low output drives standard CMOS inputs directly. R1 and C1 are optional and recommended only if supply ripple exceeds 50 mV RMS.

How does the AGC4 setting in TSOP75438WTR improve noise immunity?

The AGC4 setting in TSOP75438WTR dynamically reduces receiver sensitivity during strong ambient IR disturbances-such as those from fluorescent lamps with electronic ballasts-preventing false triggering. Unlike AGC2 variants, AGC4 prioritizes noise suppression over code compatibility, making it ideal for environments with 20–100 kHz switching noise sources, as validated in Fig. 14 and Fig. 15 of the datasheet.

Is TSOP75438WTR qualified for automotive applications?

No, TSOP75438WTR is explicitly stated in the Vishay documentation as "not qualified to automotive specifications." Its operating temperature range (−25 °C to +85 °C) and qualification scope exclude AEC-Q200 stress testing. For automotive use, Vishay recommends the TSOP48xx or TFDU series, which undergo full automotive qualification including extended temperature and humidity testing.

What is the minimum burst length and inter-burst gap required for reliable TSOP75438WTR operation?

TSOP75438WTR requires a minimum burst length of 10 cycles at 38 kHz and a minimum inter-burst gap of ≥12 cycles. For bursts longer than 70 cycles, the gap must exceed 15× the burst length. These timing constraints ensure proper AGC settling and envelope detection, as defined in the "Suitable Data Format" section and verified in Fig. 8 of the datasheet.