Texas Instruments DS250DF230ZLSR

Overview

DS250DF230ZLSR from Texas Instruments is a dual-channel, multi-rate retimer IC designed for 25-Gbps serial link signal integrity restoration. It independently locks to data rates from 19.6 to 25.8 Gbps (including sub-rates like 12.16512 Gbps and 9.8304 Gbps), delivers ultra-low latency (<500 ps typical at 25.78125 Gbps), supports up to 35-dB channel loss at 12.9 GHz, and integrates adaptive CTLE/DFE equalization with on-chip eye-opening monitoring - deployed in 100GbE front-port optical interfaces and QSFP28 active cable assemblies.

For engineers reviewing the DS250DF230ZLSR datasheet, DS250DF230ZLSR pinout, DS250DF230ZLSR application, or DS250DF230ZLSR equivalent, key selection considerations include its dual-channel independent lock range, integrated 2×2 cross-point switching, single 2.5-V supply operation, recovered clock availability on Channel 0, and support for SMBus configuration without external reference clock.

Technical Context

The DS250DF230ZLSR implements a full CDR-based retiming architecture per channel, combining adaptive continuous-time linear equalization (CTLE) and decision feedback equalization (DFE) to compensate for frequency-dependent loss and inter-symbol interference across temperature-varying channels. Its low-jitter 3-tap FIR transmitter enables precise output shaping, while the integrated 2×2 cross-point provides lane routing flexibility for fanout, multiplexing, or lane swapping.

Each channel operates autonomously with independent lock detection, adaptive EQ convergence, and programmable CDR modes (Normal/Fast Lock). The device supports both SMBus slave and master configuration via external EEPROM, with 4-level address strapping enabling up to 16-device daisy-chained management on a single bus - all powered from a single 2.5-V supply with no external low-jitter reference required.

Key Specifications

Pinout & Package

The DS250DF230ZLSR is housed in a 36-pin NFBGA package (ZLS) with 5.0 mm × 5.0 mm body size and 0.5-mm pitch. The package features 12 ground pins, 4 VDD pins, and dedicated high-speed differential I/Os arranged to minimize crosstalk and support controlled-impedance routing. Thermal performance is optimized via internal die attach and symmetric pin layout.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar retimer applications.

Compared with DS250DF230RTV, the DS250DF230ZLSR offers identical signal integrity performance in a smaller-footprint NFBGA ideal for compact optical modules, while DS125DF410 lacks the 25-Gbps capability and cross-point integration required for next-generation interconnects - making DS250DF230ZLSR the only option meeting full OIF-CEI-25G-LR and IEEE 802.3bj specifications.

Availability

DS250DF230ZLSR is available at Aetrix Electronics and suitable for 100GbE optical transceivers, InfiniBand EDR backplanes, and QSFP28 active cable assemblies requiring stable component supply, long-term lifecycle assurance, and traceable sourcing for production ramp.

Supply support for DS250DF230ZLSR 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and high-speed interface solutions, with decades of expertise in signal integrity and retimer design for datacenter and telecom infrastructure.

The DS250DF230ZLSR belongs to TI's high-speed retimer product line, engineered specifically for 25+ Gbps serial link restoration in optical front-ports, active cables, and backplane interconnects - addressing jitter accumulation, loss compensation, and multi-rate interoperability challenges.

FAQ

What data rates does the DS250DF230ZLSR support?

The DS250DF230ZLSR supports full-rate operation from 19.6 to 25.8 Gbps, plus half-rate (9.8–12.9 Gbps) and quarter-rate (4.9–6.45 Gbps) modes. Confirmed supported sub-rates include 12.16512 Gbps, 9.8304 Gbps, and 6.144 Gbps - all verified in the device's electrical characteristics table and lock-range testing. This enables direct use in 100GbE, InfiniBand EDR, and OIF-CEI-25G-LR applications without firmware modification.

Does the DS250DF230ZLSR require an external reference clock?

No, the DS250DF230ZLSR operates without an external low-jitter reference clock. It uses an internal calibration clock derived from a 30.72-MHz or 25-MHz single-ended LVCMOS input (CAL_CLK_IN), which has relaxed phase noise requirements. This eliminates clock distribution complexity and reduces system BOM cost - a key differentiator versus competing retimers requiring precision oscillators.

How is the DS250DF230ZLSR configured - SMBus or EEPROM?

The DS250DF230ZLSR supports both SMBus slave mode (direct register access) and SMBus master mode (auto-loading from external EEPROM). Up to 16 devices can share a single EEPROM using common-channel configuration. Configuration is latched at power-on reset, and the device provides ALL_DONE_N and INT_N signals to indicate load success or error conditions - enabling robust, scalable system initialization.

What is the thermal performance difference between DS250DF230ZLSR and DS250DF230RTV?

The DS250DF230ZLSR (NFBGA) has RθJA = 49.3°C/W on a 4-layer JEDEC board, while the DS250DF230RTV (QFN) achieves 30.3°C/W due to its exposed thermal pad (DAP) connected to ground. This allows the RTV variant to sustain full 2-channel operation at higher ambient temperatures - up to 105°C PCB temperature - whereas the ZLSR is rated for 85°C ambient per recommended operating conditions.

Can the DS250DF230ZLSR provide a recovered clock output?

Yes, the DS250DF230ZLSR provides a recovered clock from Channel 0 via the TEST0/RCK0 pin, configurable through register programming. When enabled, this 2.5-V LVCMOS output delivers the cleaned, retimed clock for system synchronization - eliminating the need for external clock buffers in applications such as FPGA-based timing alignment or SERDES reference clock recovery.