STMicroelectronics TSH511CFT

Overview

TSH511CFT from STMicroelectronics is a dual FM analog infrared receiver IC designed for high-fidelity stereo audio demodulation in 0.4–11 MHz carrier systems. It integrates two independent RF signal chains - each with LNA (22 dB gain), intermediate amplifier, limiter, quadrature FM demodulator, and audio buffer - delivering 20 mW per channel into 16 Ω loads with 4 µV sensitivity at 12 dB SINAD. It enables direct photodiode coupling and supports mono/stereo headset and multimedia IR audio applications.

For engineers reviewing the TSH511CFT datasheet, TSH511CFT pinout, TSH511CFT application, or TSH511CFT equivalent, key selection criteria include dual-channel FM demodulation capability, integrated 20 mW headphone drivers, standby-controlled current reduction (down to 9.5 mA), squelch-controlled mute ramping, and 44-pin TQFP package compatibility with IR stereo receiver PCB layouts.

Technical Context

The TSH511CFT implements two fully independent FM receiver paths sharing a common LNA input stage, with dedicated AMP, limiter, and quadrature demodulator sections per channel. Each path provides 50–60 dB limiter gain and delivers 700–900 mVRMS demodulated audio output into 4 kΩ load.

Its squelch circuit uses an internal noise amplifier and comparator (9 mVRMS threshold, 1 mVRMS hysteresis) to control mute ramping via external capacitor on pin 25, while standby pins SBY1/31 and SBY2/32 allow selective shutdown of RX1, RX2, or both - enabling mono operation with 30% lower supply current.

Key Specifications

Pinout & Package

Package: TQFP-44 (10 × 10 mm, 0.8 mm pitch), thermally enhanced with exposed thermal pad (pin 27 GND).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TS4962IST and MAX9867ETJ+, the TSH511CFT uniquely integrates complete dual FM receiver signal chains - including LNA, limiter, quadrature demodulator, and 20 mW headphone drivers - making it irreplaceable in analog IR stereo receiver applications requiring minimal external components and direct photodiode interfacing.

Availability

TSH511CFT is available at Aetrix Electronics and suitable for infrared stereo headsets, multimedia IR audio systems, and power-line carrier intercoms requiring stable component supply across extended temperature ranges (−40°C to +85°C) and long-lifecycle production.

Supply support for TSH511CFT 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, specializing in analog, mixed-signal, and power management ICs for industrial, automotive, and consumer markets.

The TSH511CFT belongs to ST's infrared audio receiver product line, engineered specifically for high-sensitivity, low-power stereo IR demodulation in battery-operated headsets and multimedia peripherals.

FAQ

What is the minimum supply voltage for reliable operation of the TSH511CFT?

The TSH511CFT operates reliably down to 2.3 V, as confirmed by electrical characteristics tables and typical application schematics. At this voltage, it maintains 20 mW output into 16 Ω, 4 µV sensitivity, and functional squelch behavior - validated across −40°C to +85°C ambient temperature.

Can the TSH511CFT drive 32 Ω headphones effectively?

Yes - the audio buffers deliver 15–20 mW into 16 Ω and maintain ≤0.8% THD at 32 Ω loads per Figure 9 and Table 4. Output power drops to ~10 mW at 32 Ω, but SNR remains >58 dB and bandwidth exceeds 35 kHz, preserving hi-fi fidelity for higher-impedance earpieces.

How does the squelch function respond to weak carrier signals?

The squelch circuit monitors RF noise amplitude at the limiter output, comparing it against a 9 mVRMS threshold (adjustable via RMUTE resistor). When carrier level falls below threshold, MUTE-OUT (pin 25) ramps low over ~10 ms (with 100 nF capacitor), muting both audio buffers smoothly to prevent pop/click artifacts.

Is the TSH511CFT pin-compatible with any newer STMicroelectronics receivers?

No - the TSH511CFT has no direct pin-compatible successor. ST discontinued the TSH5xx family after 2010, and newer IR receivers (e.g., STP16DP05) use digital I²S output and lack analog FM demodulation. Migration requires redesigning RF front-end, demodulation, and audio buffering stages.