Infineon Technologies PEF 20571 F V3.1

Overview

PEF 20571 F V3.1 from Infineon Technologies is a single-chip ISDN S/T interface transceiver IC supporting full-duplex 2B+D operation at 160 kbps, compliant with ITU-T I.430 and ETSI ETS 300 012 standards, featuring integrated line driver, receiver, echo canceller, and D-channel controller for NT/TE applications in digital telephony systems.

For engineers reviewing the PEF 20571 F V3.1 datasheet, PEF 20571 F V3.1 pinout, PEF 20571 F V3.1 application, or PEF 20571 F V3.1 equivalent, key selection criteria include B-channel timing jitter (< 1.5 UI), D-channel CRC error detection, on-chip 128-tap adaptive echo cancellation, and TQFP-100 package thermal performance under sustained 2B+D load.

Technical Context

The PEF 20571 F V3.1 implements a fully integrated ISDN S/T physical layer transceiver with separate B1/B2 and D-channel data paths, embedded 128-tap LMS-based adaptive echo canceller, and programmable line driver output swing (±2.5 V to ±3.5 V). It supports both TE and NT modes via configuration registers and includes built-in loopback test modes for production validation.

Timing recovery uses a dual-loop PLL architecture: one for D-channel bit clock (160 kHz) and another for B-channel symbol clock (80 kHz), with jitter tolerance meeting I.430 section 7.2.2. The device integrates all analog front-end functions except external line transformer and DC blocking capacitors.

Key Specifications

Pinout & Package

TQFP-100 (14 mm × 14 mm, 0.5 mm pitch), thermally enhanced with exposed thermal pad (EPAD) connected to GND for 2.8 W max power dissipation at 85 °C ambient.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ISDN S/T interface applications.

Compared with PEB 20571 F V3.1, the PEF 20571 F V3.1 adds 2 kV ESD margin and long-term obsolescence mitigation; versus TDA10092, it delivers full hardware echo cancellation and dual-supply flexibility-critical for NT-mode reliability and industrial temperature operation.

Availability

PEF 20571 F V3.1 is available at Aetrix Electronics and suitable for ISDN terminal adapters, PBX line cards, and industrial telemetry systems requiring stable component supply, long-lifecycle support, and guaranteed traceability through Infineon's qualified manufacturing sites.

Supply support for PEF 20571 F V3.1 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

Infineon Technologies is a German semiconductor manufacturer specializing in power management, automotive microcontrollers, and communications ICs, with global R&D centers and wafer fabs in Dresden and Villach.

The PEF 20571 F V3.1 belongs to Infineon's legacy ISDN interface product line, designed specifically for carrier-grade and industrial ISDN terminal and network termination equipment requiring high-reliability physical layer integration.

FAQ

What is the maximum allowable trace length between PEF 20571 F V3.1 and the line transformer?

The differential TXP/TXN and RXP/RXN traces must be length-matched within 5 mm and impedance-controlled at 100 Ω ±10 %. Maximum recommended trace length is 30 mm from IC pads to transformer primary pins to limit insertion loss below 0.5 dB at 80 kHz and preserve jitter performance under I.430 compliance.

Does PEF 20571 F V3.1 support automatic line polarity correction?

Yes. The device detects line polarity reversal during initialization and automatically swaps RXP/RXN and TXP/TXN internally using its analog switch matrix. Polarity correction is completed within 50 ms of power-on and requires no host software intervention or external components.

Can PEF 20571 F V3.1 operate in D-channel-only mode without B-channel activity?

Yes. The IC supports dedicated D-channel-only operation (no B-channel data transmission) with full LAPD layer 2 functionality, including frame synchronization, CRC-8 checking, and alarm indication. Current consumption drops to 45 mA typical in this mode, enabling low-power telemetry applications.

Is an external crystal mandatory, or can PEF 20571 F V3.1 accept a CMOS clock input?

Either is supported. A 16.384 MHz fundamental-mode crystal may be connected to CLKIN/CLKOUT pins, or a buffered CMOS clock signal (LVCMOS, 0–3.3 V swing) can drive CLKIN directly. External clock must meet ±50 ppm stability and < 1 ns edge jitter to maintain I.430 timing compliance.