Infineon Technologies PEF 24901 H V2.2

Overview

PEF 24901 H V2.2 from Infineon Technologies is a quad-channel ISDN digital front-end IC implementing the 4B3T line coding scheme and integrated echo cancellation for U-interface transceivers. It operates at 144 kbit/s per BRI channel, supports ITU-T G.961 compliance, features IOM®-2 interface with MON-12 protocol, and integrates frame synchronization, scrambler/descrambler, and maintenance channel logic for telephony access networks.

For engineers reviewing the PEF 24901 H V2.2 datasheet, PEF 24901 H V2.2 pinout, PEF 24901 H V2.2 application, or PEF 24901 H V2.2 equivalent, key selection criteria include 4B3T encoding fidelity, U-transceiver state machine behavior, IOM®-2 timing alignment with analog front-end (PEF 24902), and MON-12 register-access protocol implementation for layer-1 diagnostics and activation control.

Technical Context

The PEF 24901 H V2.2 implements a deterministic U-transceiver state machine with LT-mode entry/exit governed by C/I codes (e.g., AR1, AI, DC), real-time reaction times replacing double-last-look criteria, and synchronized 1 ms frame clocking via CLS0–CLS3 pins. It interfaces exclusively with the AFE V2.1 (PEF 24902) analog front-end using dedicated digital signals including CLOCK, FSC, DCL, and DATA.

Its functional core includes 4B3T encoder/decoder with ternary signal element validation, block error counter with violation monitoring, awake protocol support, and transparent test loop modes (Loopback #1, Repeater #4). Clock generation derives from an external 15.36 MHz source, with FSC and CLOCK required to originate from the same oscillator to ensure phase coherence.

Key Specifications

Pinout & Package

PEF 24901 H V2.2 is housed in a 64-pin LQFP package (10 mm × 10 mm, 0.5 mm pitch) with exposed thermal pad. Pin assignments are defined per DS1, Sep. 2002, with dedicated IOM®-2 data/control lines, frame sync outputs, analog interface signals, JTAG test pins, and power/ground terminals.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ISDN digital front-end applications.

Compared with PEF 24901 H V1.2, the V2.2 revision delivers stricter C/I code validation, deterministic LT-mode timing, and simplified MON-12-only diagnostics-critical for carrier-grade activation reliability. Versus PEF 24901 E V2.2, the H variant provides enhanced thermal performance via exposed pad, making it preferable for sustained 4-channel operation in compact line cards.

Availability

PEF 24901 H V2.2 is available at Aetrix Electronics and suitable for ISDN NT1 equipment, DSLAM line cards, enterprise PBX interfaces, and remote access server front-ends requiring stable component supply and long-term lifecycle support.

Supply support for PEF 24901 H V2.2 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 AG is a German semiconductor manufacturer specializing in power management, automotive ICs, security controllers, and wired/wireless communications solutions.

The PEF 24901 belongs to Infineon's Digital Front End (DFE-T) product line, designed specifically for ISDN U-interface physical layer implementation in carrier and enterprise access infrastructure-emphasizing G.961 compliance, multi-channel integration, and field-diagnostic readiness.

FAQ

What is the role of the MON-12 protocol in PEF 24901 H V2.2?

MON-12 is the exclusive monitor command protocol for PEF 24901 H V2.2, enabling direct 16-bit register read/write access to TEST, LOOP, and status registers. Unlike earlier versions, MON-0 and MON-8 are removed; MON-12 commands execute immediately without polling delay and support full diagnostic control of the U-transceiver state machine and test loops.

Can PEF 24901 H V2.2 operate without an external analog front-end?

No. The PEF 24901 H V2.2 is strictly the digital front-end and requires pairing with the AFE V2.1 (PEF 24902) analog front-end. Signals like DATA, DCL, CLOCK, and FSC are defined for bidirectional interaction with that specific companion IC; standalone operation is not supported or characterized.

Why must CLOCK and FSC be sourced from the same oscillator?

DS1 Section 1.3 and Figure 4 mandate CLOCK and FSC derive from the same 15.36 MHz source to maintain strict phase alignment. This ensures deterministic timing between frame boundaries (FSC) and bit sampling (CLOCK), preventing metastability in the 4B3T decoder and guaranteeing reliable syncword detection per ITU-T G.961 timing budgets.

What happens during U-transceiver deactivation in PEF 24901 H V2.2?

When the U-transceiver enters the Deactivated state (e.g., via C/I=DC command) and no MONITOR message is pending, the DFE-T automatically enters power-down mode per Section 4.2. This reduces current consumption significantly; recovery requires hardware reset or explicit activation sequence-not automatic wake-on-ring or line activity.