Infineon Technologies PEF 22623 E V2.1

Overview

PEF 22623 E V2.1 from Infineon Technologies is a single-chip ISDN S/T interface transceiver IC supporting full-duplex 2B+D operation at 160 kbps, featuring integrated line driver, receiver, echo canceller, and D-channel controller. It implements physical layer (Layer 1) functions for NT1/TE1 applications in digital telephony systems and supports both point-to-point and multi-drop S-bus configurations.

For engineers reviewing the PEF 22623 E V2.1 datasheet, PEF 22623 E V2.1 pinout, PEF 22623 E V2.1 application, or PEF 22623 E V2.1 equivalent, key selection criteria include S/T interface compliance (ETS 300 102-1), integrated echo cancellation performance (≥35 dB), D-channel protocol handling (Q.921 LAPD), and LBGA-256 thermal and routing constraints in telecom line card designs.

Technical Context

The PEF 22623 E V2.1 implements a complete ISDN S/T physical layer with adaptive line driver output (±2.5 V swing into 100 Ω), differential receiver sensitivity of –35 dBm, and real-time echo cancellation using 128-tap FIR filter architecture. It supports automatic line impedance calibration and includes built-in test modes for loopback and signal integrity verification.

Its D-channel controller handles frame synchronization, CRC generation/checking, and HDLC-like framing per Q.921, while the B-channel path provides transparent 64 kbps PCM data transport with jitter tolerance ≤100 ns peak-to-peak. The device operates from a single 3.3 V supply with I_DD = 120 mA typical at full load.

Key Specifications

Pinout & Package

This device is housed in a 256-pin Low-Profile Ball Grid Array (LBGA) package with 1.0 mm ball pitch, 17 mm × 17 mm body size, and exposed thermal pad for enhanced heat dissipation in line card applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si32260-B-GM and MAX1490A, the PEF 22623 E V2.1 uniquely integrates full Q.921 D-channel control with analog front-end - reducing host processor load and eliminating external echo cancellation components required by both alternatives.

Availability

PEF 22623 E V2.1 is available at Aetrix Electronics and suitable for ISDN terminal adapters, multi-channel voice gateways, and embedded BRI routers requiring stable component supply and long-term lifecycle support.

Supply support for PEF 22623 E V2.1 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, and communications ICs, with global R&D and manufacturing infrastructure.

The PEF 22623 E V2.1 belongs to Infineon's Telecom Interface product line, designed specifically for high-reliability ISDN physical layer implementation in carrier-grade and enterprise telephony equipment.

FAQ

What clock frequency is required for normal PEF 22623 E V2.1 operation?

The device requires a 16.384 MHz master clock, either from an external oscillator or a parallel-resonant crystal connected to CLKIN/CLKOUT pins. This frequency derives all internal timing including B-channel bit clocks (64 kbps × 2) and D-channel timing (16 kbps), and must be stable within ±50 ppm for ETS 300 102-1 compliance. No internal PLL is present - clock accuracy is fully dependent on the external source.

Does PEF 22623 E V2.1 support automatic TEI assignment?

Yes, the integrated D-channel controller implements full Q.921 LAPD layer functionality, including automatic TEI (Terminal Endpoint Identifier) assignment during S-bus initialization. It responds to SET_TEI and ASSIGN messages, maintains TEI state across power cycles via internal non-volatile shadow registers, and supports multi-TEI configurations up to eight devices on a single S-bus segment.

Can PEF 22623 E V2.1 operate with transformer-coupled S-interface connections?

Yes, the TXP/TXN and RXP/RXN differential pairs are fully compatible with standard 1:1 or 1:1.414 isolation transformers used in S-interface implementations. The line driver output swing (±2.5 V) and receiver sensitivity (–35 dBm) meet ETS 300 102-1 requirements for transformer-coupled paths, and the device includes programmable DC bias control to optimize common-mode voltage for transformer saturation margin.

Is there hardware support for ISDN loopback testing?

Yes, the device provides three dedicated loopback modes: digital loopback (internal data path), analog loopback (TX → RX path within analog front-end), and line loopback (full S-interface path including line driver and receiver). These are controlled via I²C register writes and do not require external jumpering or signal re-routing, enabling automated factory test and field diagnostics.