Vishay Semiconductor Opto Division TSOP38538

Overview

TSOP38538 from Vishay Semiconductors is a 38 kHz infrared (IR) receiver module with AGC5 configuration, optimized for very noisy environments and short-burst remote control protocols including XMP, RECS-80, r-map, and RCMM. It features active-low demodulated output, operates from 2.0 V to 5.5 V, draws only 0.35 mA typical supply current, and delivers 26 m transmission range with TSAL6200 emitter under dark ambient conditions.

For engineers reviewing the TSOP38538 datasheet, TSOP38538 pinout, TSOP38538 application, or TSOP38538 equivalent, this device is selected for noise-immune IR reception in consumer electronics remote systems where high AGC performance is required to suppress fluorescent lamp interference, Wi-Fi emissions, and LCD TV noise without sacrificing burst-length compatibility.

Technical Context

The TSOP38538 integrates a PIN photodiode, preamplifier, bandpass filter, demodulator, and AGC control circuit in a single epoxy package with built-in IR filter. Its AGC5 setting provides maximum noise suppression by dynamically reducing sensitivity during strong ambient disturbances while maintaining detection of valid 38 kHz modulated bursts as short as 6 carrier cycles.

It employs envelope-based signal discrimination: valid data must meet strict constraints on burst length (6–20 cycles), inter-burst gap (≥10 cycles), and maximum envelope duty cycle (e.g., ≤25× burst length). Output is open-collector compatible, active-low, and directly interfaces with microcontrollers without external level-shifting.

Key Specifications

Pinout & Package

TSOP38538 uses a 3-pin Minicast surface-mount package (5.0 mm × 6.95 mm × 4.8 mm) with gull-wing leads, leaded mounting, and integrated IR filter epoxy encapsulation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TSOP38338 and TSOP38138, the TSOP38538 provides the highest AGC gain control depth and tightest burst validation window (6–20 cycles), making it the only variant qualified for deployment in environments with co-located high-modulation fluorescent ballasts and dense 2.4 GHz RF activity - at the expense of reduced tolerance for longer or irregular burst formats.

Availability

TSOP38538 is available at Aetrix Electronics and suitable for TV remote controls, set-top box interfaces, home theater system receivers, and smart appliance remotes requiring stable component supply, consistent AGC5 performance, and long-term lifecycle support.

Supply support for TSOP38538 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 Intertechnology is a global semiconductor manufacturer specializing in discrete components, sensors, and optoelectronics with emphasis on reliability, precision, and application-specific integration.

The TSOP38538 belongs to Vishay's TSOP38x family of IR receiver modules designed specifically for noise-resilient, short-burst remote control systems in consumer and industrial environments - not automotive-qualified.

FAQ

What is the carrier frequency of the TSOP38538 and why is it important?

The TSOP38538 is tuned to a precise 38 kHz carrier frequency, which matches industry-standard remote control protocols such as RCMM, XMP, RECS-80, and r-map. This frequency ensures optimal signal-to-noise ratio and enables the internal bandpass filter to reject out-of-band interference from ambient light sources and electronic noise. Using TSOP38538 in a 38 kHz system guarantees full compatibility with common IR emitters like the TSAL6200 and avoids false triggering or missed commands.

How does the AGC5 setting in TSOP38538 differ from AGC1 or AGC3 variants?

The AGC5 setting in TSOP38538 provides the highest level of automatic gain control, dynamically attenuating sensitivity during strong ambient IR disturbances - such as those from high-modulation fluorescent lamps or Wi-Fi transceivers - to prevent false outputs. Unlike TSOP38138 (AGC1) or TSOP38338 (AGC3), TSOP38538 enforces stricter burst validation (6–20 cycles) and shorter inter-burst gaps (≥10 cycles), trading protocol flexibility for superior noise immunity in electrically hostile environments.

Can TSOP38538 be used with a 3.3 V microcontroller without level shifting?

Yes, TSOP38538 operates natively from 2.0 V to 5.5 V and features an open-collector active-low output. When powered at 3.3 V, its output can be pulled up to the same 3.3 V rail used by the microcontroller I/O, enabling direct connection without level-shifting circuitry. The output voltage low remains ≤100 mV at 0.5 mA sink current, ensuring solid logic-low recognition by standard CMOS inputs.

What is the minimum irradiance required for TSOP38538 to detect an XMP-coded signal?

The TSOP38538 requires a minimum irradiance of 0.15 mW/m² (typical) to reliably detect XMP-coded signals under standard test conditions (Tamb = 25 °C, dark ambient). This threshold is confirmed in the Vishay datasheet Table "Electrical and Optical Characteristics" and reflects the device's high sensitivity enabled by AGC5's optimized gain profile and low-noise preamplifier design - critical for compact remotes with limited LED drive current.

Is TSOP38538 qualified for automotive applications?

No, TSOP38538 has not been qualified to AEC-Q200 or any automotive-grade specifications. The datasheet explicitly states these components "have not been qualified to automotive specifications" and specifies an operating temperature range of −25 °C to +85 °C - narrower than typical automotive requirements. TSOP38538 is intended for consumer electronics, home appliances, and industrial remote interfaces where extended temperature or vibration qualification is not mandated.