Analog Devices Inc./Maxim Integrated DS21600N+

Overview

DS21600N+ from Maxim Integrated is a 3.3V/5V dual-output clock rate adapter IC for E-carrier/T-carrier interconversion, providing CLKOUT1 (1.544 MHz or 2.048 MHz), CLKOUT2 (6.144–6.176 MHz), and a frequency-locked 8 kHz SYNCOUT. It operates across industrial temperature range (−40°C to +85°C) in an 8-pin DIP package and supports frame-sync alignment with SYNCIN.

For engineers reviewing the DS21600N+ datasheet, DS21600N+ pinout, DS21600N+ application, or DS21600N+ equivalent, this page delivers verified clock conversion modes, jitter performance per G.823/TR62411, phase-alignment timing, supply flexibility, and drop-in compatibility with LXP600A-series devices.

Technical Context

The DS21600N+ implements a PLL-based analog clock synthesis architecture with feedback divider and frame-sync generator. Its mode-select logic (SEL pin) determines whether CLKIN = 1.544 MHz yields CLKOUT1 = 2.048 MHz / CLKOUT2 = 6.144 MHz, or CLKIN = 2.048 MHz yields CLKOUT1 = 1.544 MHz / CLKOUT2 = 6.176 MHz.

All outputs are frequency-locked to CLKIN; phase alignment of CLKOUT1, CLKOUT2, and SYNCOUT to SYNCIN occurs within ≤50 ms when SYNCIN = 8 kHz. Jitter transfer peaks at ~1.6× gain in 4–8 kHz band, distinct from legacy LXP60x's 20–40 kHz peak.

Key Specifications

Pinout & Package

DS21600N+ uses an 8-pin plastic dual in-line package (PDIP), pin-compatible with LXP600A-series DIP variants. Pin functions are electrically identical across DS21600/DS21602/DS21604 DIP versions.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar clock rate adaptation applications.

Compared with LXP600ASE and DS21600SN+, the DS21600N+ uniquely combines 3.3 V/5 V operation, lower jitter, and DIP packaging - making it the only option for upgrading legacy LXP600A-based systems to dual-voltage support without changing mounting method.

Availability

DS21600N+ is available at Aetrix Electronics and suitable for T1/E1 line interface units, digital cross-connect systems, channelized framer boards, and legacy telecom gateways requiring stable component supply across long product lifecycles.

Supply support for DS21600N+ 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 U.S.-based semiconductor company specializing in precision analog, mixed-signal, and power management ICs for industrial, communications, and computing markets.

The DS21600N+ belongs to Maxim's telecom timing portfolio, designed specifically to replace obsolete LXP60x clock adapters in carrier-grade TDM infrastructure with enhanced voltage flexibility and jitter performance.

FAQ

What clock conversion modes does the DS21600N+ support?

The DS21600N+ supports two bidirectional E/T-carrier clock conversions: when SEL = 0, it converts 1.544 MHz CLKIN to 2.048 MHz CLKOUT1 and 6.144 MHz CLKOUT2; when SEL = 1, it converts 2.048 MHz CLKIN to 1.544 MHz CLKOUT1 and 6.176 MHz CLKOUT2. All modes deliver a frequency-locked 8 kHz SYNCOUT. These modes are confirmed in Table 2-A of the DS21600N+ datasheet and match the DS21600 family specification.

Is the DS21600N+ pin-compatible with the LXP600A series?

Yes, the DS21600N+ is a direct drop-in replacement for LXP600A, LXP602, and LXP604 in DIP packages, with identical pin numbering, signal names, and electrical behavior. Table 1-B confirms pin name cross-reference (e.g., CLKIN ↔ CLKI, SYNCIN ↔ FSI), and the "Direct Drop-In Replacement" feature explicitly states compatibility. No PCB or schematic changes are needed when substituting DS21600N+ for LXP600ASE in 8-pin DIP layouts.

Does the DS21600N+ support both 3.3 V and 5 V operation simultaneously?

No, the DS21600N+ operates from a single supply rail - either 3.3 V ±5% or 5 V ±5%, selected at power-up. It does not support dual-supply operation. The supply voltage must be stable within tolerance during operation; mixing rails or dynamically switching is not supported. This is specified in the "RECOMMENDED DC OPERATING CONDITIONS" table, where VDD lists separate min/typ/max values for each voltage.

How does SYNCIN affect phase alignment of DS21600N+ outputs?

When SYNCIN is asserted (8 kHz or integer subrate), DS21600N+ aligns the rising edges of CLKOUT1, CLKOUT2, and SYNCOUT to SYNCIN within ≤50 ms. Figure 4-1 through 4-5 show precise timing relationships, and Section 2.2 states phase synchronization occurs deterministically. SYNCIN must be tied high or low when unused to prevent metastability. This behavior is intrinsic to the DS21600N+'s frame-sync generator block, as shown in Figure 1-1.

What is the jitter performance of DS21600N+ under G.823 compliance testing?

The DS21600N+ achieves 0.018 UI_P-P typical and 0.035 UI_P-P maximum jitter (20 Hz–100 kHz band) for 1.544 MHz → 2.048 MHz conversion, meeting ITU-T G.823 Class I mask requirements. Table 3-A specifies these values, and the note clarifies they apply to DS21600/DS21602/DS21604 family devices including DS21600N+. This performance enables use in primary reference clock applications within carrier networks.