Analog Devices Inc./Maxim Integrated DS26401A2+

Overview

DS26401A2+ from Maxim Integrated is an octal T1/E1/J1 framer IC with eight independent framer/formatters, full-feature BERT, internal clock adapter (CLAD), and 8-bit parallel control port supporting Intel/Motorola bus modes. It operates on a single 3.3V supply with 5V-tolerant inputs and targets telecom line cards, routers, and DSLAMs requiring synchronized TDM backplane timing at 1.544MHz–16.384MHz.

For engineers reviewing the DS26401A2+ datasheet, DS26401A2+ pinout, DS26401A2+ application, or DS26401A2+ equivalent, key selection considerations include software-selectable T1/E1/J1 framing per channel, HDLC controller per framer, elastic store buffers for Tx/Rx, BERT mapping flexibility, and support for AMI/B8ZS/HDB3/NRZ line coding in carrier-grade access equipment.

Technical Context

The DS26401A2+ implements eight fully independent T1/E1/J1 framer channels, each with dedicated transmit/receive paths, two-frame elastic store buffers, and programmable signaling extraction/insertion. Its HDLC controllers map to any DS0 or FDL/Sa bit, enabling granular channel-level protocol handling.

System-level timing is managed via the internal CLAD clock generator (16.384/8.192/4.096/2.048MHz outputs) and a flexible TDM backplane interface supporting bus rates from 1.544MHz to 16.384MHz. JTAG boundary scan and BERT diagnostics are integrated for production test and field validation.

Key Specifications

Pinout & Package

DS26401A2+ is housed in a 17mm × 17mm, 256-pin BGA package with 1.00mm pitch. Pin assignments follow Maxim's standardized signal grouping for framer devices, including dedicated receive/transmit data buses, control port signals (RD, WR, CS, A0–A7), clock inputs (RSYNC, TSSYNC), and JTAG interface (TCK, TMS, TDI, TDO).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal T1/E1 framer applications.

Compared with DS2155 and MC2833, DS26401A2+ delivers higher integration (BERT + CLAD + 8-channel framing), broader standard support (T1/E1/J1), and superior timing control via elastic stores and programmable synchronizers - making it optimal for next-generation multi-standard access equipment.

Availability

DS26401A2+ is available at Aetrix Electronics and suitable for line cards, routers, and DSLAMs requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing for telecom infrastructure programs.

Supply support for DS26401A2+ 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

Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in high-performance analog, mixed-signal, and RF solutions for communications, computing, and industrial markets.

The DS26401A2+ belongs to Maxim's Telecom Framer product line, designed specifically for carrier-grade TDM access equipment requiring multi-standard framing, precise timing control, and integrated diagnostics in space-constrained line cards.

FAQ

What is the operating temperature range for DS26401A2+?

The DS26401A2+ is rated for commercial temperature operation from 0°C to +70°C. This specification aligns with the DS26401 variant listed in Maxim's official ordering information and is validated for use in controlled-environment telecom equipment such as enterprise routers and central office line cards where ambient thermal conditions remain within this range. DS26401A2+ does not support extended industrial or automotive temperature grades.

Does DS26401A2+ support both T1 and E1 framing simultaneously?

Yes, DS26401A2+ supports simultaneous T1 and E1 framing across its eight independent channels. Each framer can be individually configured for T1 (D4 or ESF), E1 (G.704), or J1 mode via software register settings. This per-channel configurability allows mixed-mode operation - for example, four ports in T1 mode and four in E1 mode - without hardware changes or performance trade-offs.

What clock frequencies does the internal CLAD generator provide in DS26401A2+?

The internal clock adapter (CLAD) in DS26401A2+ generates four fixed-frequency outputs: 16.384MHz, 8.192MHz, 4.096MHz, and 2.048MHz. These frequencies are selected via register-controlled dividers from a master oscillator and are used for backplane synchronization, HDLC timing, and system clock distribution. No external PLL components are required to achieve these outputs.

Is DS26401A2+ pin-compatible with earlier DS26401 revisions?

Yes, DS26401A2+ maintains identical pinout and package (256-pin BGA, 17mm × 17mm, 1.00mm pitch) with all prior DS26401 variants including DS26401 and DS26401N. The 'A2' suffix denotes a specific fabrication revision with documented errata handling, but mechanical and electrical interface compatibility is preserved across the DS26401 family for drop-in replacement in existing designs.

How is BERT functionality implemented in DS26401A2+?

DS26401A2+ integrates a full-feature BERT (Bit Error Rate Tester) that can be mapped to any of its eight T1/E1 ports via register configuration. It supports pseudorandom pattern generation (2^15–1, 2^23–1), error detection, BER calculation, and error injection - all without external test equipment. BERT operation is synchronized to the selected port's line clock, enabling accurate in-service link validation.