Infineon Technologies CY7B923-SC

Overview

CY7B923-SC from Cypress Semiconductor is a Fibre Channel– and ESCON-compliant HOTLink™ transmitter IC that converts 8-bit parallel TTL data into three differential PECL 100K serial outputs (OUTA±, OUTB±, OUTC±) at rates from 160–330 Mbps. It integrates an 8B/10B encoder, PLL-based clock multiplier, BIST pattern generator, and TTL-synchronous I/O-enabling direct interface to FIFOs like CY7C42X/CY7C44X. Used in high-speed point-to-point links for video transmission equipment and mass storage interconnects.

For engineers reviewing the CY7B923-SC datasheet, CY7B923-SC pinout, CY7B923-SC application, or CY7B923-SC equivalent, key selection criteria include its triple PECL output capability, 8B/10B encoding control via SC/D and MODE pins, FOTO-driven fiber-optic module disable function, and built-in BIST support for link-level diagnostics without external test logic.

Technical Context

The CY7B923-SC implements a fully integrated clock multiplication architecture: CKW (byte-rate clock input) drives an on-chip PLL to generate the high-speed bit clock (10× CKW), eliminating external PLL components. Its encoder supports both standard 8B/10B coding (MODE = GND) and bypass mode (MODE = VCC) for pre-encoded or scrambled streams.

Three independent PECL 100K differential outputs (OUTA±, OUTB±, OUTC±) are individually controllable-FOTO asserts logical zero on OUTA±/OUTB± to extinguish fiber-optic transmitters while leaving OUTC± active for loopback testing. BISTEN enables system-level link validation using deterministic pseudo-random patterns synchronized to ENA/ENN timing.

Key Specifications

Pinout & Package

Package: 28-pin SOIC (Small Outline Integrated Circuit), surface-mount, JEDEC MS-012AC compliant. Pin spacing: 1.27 mm; body width: 7.5 mm; thermal resistance θ_JA ≈ 120°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed serial link transmitter applications.

Compared with DS90CR285MTD and SN65LVDS31PW, the CY7B923-SC delivers protocol-specific integration (8B/10B, Fibre Channel framing), PECL output compatibility with commercial optical modules, and hardware BIST-reducing system validation time by >70% in storage and video applications.

Availability

CY7B923-SC is available at Aetrix Electronics and suitable for video transmission equipment, mass storage interconnects, and Fibre Channel node interfaces requiring stable component supply through 2028.

Supply support for CY7B923-SC 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

Cypress Semiconductor (now part of Infineon Technologies) designs high-performance mixed-signal ICs for communications, computing, and industrial systems, with expertise in interface, timing, and programmable logic solutions.

The CY7B923 belongs to Cypress's HOTLink™ family-engineered specifically for replacing parallel buses with robust, low-jitter, protocol-compliant serial links in storage, video, and telecom infrastructure.

FAQ

Can CY7B923-SC operate without an external crystal?

No. CY7B923-SC requires a stable TTL-compatible CKW input clock derived from a crystal oscillator. The internal PLL multiplies this byte-rate clock to generate the 10× bit clock; no crystal connection is made directly to the IC-it must be provided externally to CKW. Typical CKW frequencies range from 16–33 MHz to achieve 160–330 Mbps data rates.

What happens to OUTA± and OUTB± when FOTO is HIGH?

When FOTO is HIGH, OUTA± and OUTB± are forced to their "logic zero" state: OUTA+ and OUTB+ go LOW while OUTA− and OUTB− go HIGH. This extinguishes connected fiber-optic transmitter modules. OUTC± remains unaffected and continues transmitting, enabling loopback diagnostics even during optical shutdown.

Is the 8B/10B encoder optional or mandatory?

The 8B/10B encoder is configurable-not mandatory. When MODE is tied to GND, encoding is active per ANSI X3.230. When MODE is tied to VCC, the encoder is bypassed and D0–D7 plus Da–Dj pass directly to the shifter as raw 10-bit values-supporting pre-encoded or scrambled streams used in proprietary protocols.

How does BIST validate the entire link?

BIST operates cooperatively with CY7B933: CY7B923-SC transmits a deterministic 511-byte LFSR pattern while CY7B933 checks each received byte against its local LFSR. RVS output pulses LOW only when all bytes match-confirming transmitter functionality, physical link integrity, and receiver decoding accuracy in a single test cycle.