Analog Devices Inc./Maxim Integrated DS1020S-15/T&R

Overview

DS1020S-15/T&R from Dallas Semiconductor (now Maxim Integrated) is a programmable 8-bit all-silicon delay line with 0.15 ns step resolution, 10 ns inherent delay, and maximum 48.25 ns total delay. It supports both 3-wire serial and 8-bit parallel programming, delivers TTL/CMOS-compatible output, and drives up to ten 74LS loads in high-speed digital timing alignment applications.

For engineers reviewing the DS1020S-15/T&R datasheet, DS1020S-15/T&R pinout, DS1020S-15/T&R application, or DS1020S-15/T&R equivalent, key selection criteria include edge-accurate delay reproducibility, dual-programming interface flexibility, SOIC-16 surface-mount compatibility, and ±4 ns max deviation from programmed value under industrial temperature range.

Technical Context

The DS1020S-15/T&R implements an 8-bit user-programmable CMOS delay core with non-inverting signal replication after user-defined delay. Its architecture supports two distinct configuration modes: parallel mode (S=1) using P0–P7 pins for direct binary delay selection, and serial mode (S=0) using C/D/Q pins for daisy-chainable MSB-first 8-bit register loading.

Both modes require E (Enable) asserted high during programming and guarantee rising/falling edge accuracy within ±4 ns tolerance. The device features internal settling time of 50 µs after delay changes (tEDV), operates at 5.0 V ±5%, and maintains stable delay performance across 0°C to 70°C ambient temperature.

Key Specifications

Pinout & Package

DS1020S-15/T&R is packaged in a 16-pin SOIC (300-mil) surface-mount outline, pin-compatible with the DIP variant but optimized for automated assembly and space-constrained PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar programmable delay line applications.

Compared with DS1020-15, the DS1020S-15/T&R offers identical timing performance in a surface-mount package enabling automated assembly, while the MAX9622EUA+ trades programmability for lower jitter and 3.3 V compatibility-making it unsuitable as a functional replacement but viable for fixed-delay, low-noise roles.

Availability

DS1020S-15/T&R is available at Aetrix Electronics and suitable for high-speed logic skew correction, programmable clock alignment, logic-level signal retiming, and test equipment pulse delay calibration requiring stable component supply across extended production lifecycles.

Supply support for DS1020S-15/T&R 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

Dallas Semiconductor, acquired by Maxim Integrated in 2001, specialized in precision analog, timing, and secure memory ICs for industrial and communications infrastructure.

The DS1020 product line was designed to replace hybrid delay lines with fully integrated, programmable silicon alternatives offering consistent performance, solderability, and cost efficiency in digital timing subsystems.

FAQ

What is the inherent delay of DS1020S-15/T&R and how does it affect total delay calculation?

The DS1020S-15/T&R has an inherent (step-zero) delay of 10 ±2 ns, which is added to the programmable increment. For example, a binary value of 00000001 (1) yields 10.15 ns total delay (10 ns + 1 × 0.15 ns). This base delay is fixed and present regardless of programming mode or input signal edge, ensuring predictable minimum latency in DS1020S-15/T&R timing paths.

Can DS1020S-15/T&R be used in both rising- and falling-edge sensitive circuits?

Yes, DS1020S-15/T&R guarantees leading and trailing edge accuracy within ±4 ns tolerance, meaning both rising and falling edges experience identical delay values. This is confirmed in the datasheet description and verified under test conditions using 1.5 V threshold measurements. DS1020S-15/T&R is therefore suitable for bidirectional data strobes, differential clock pairs, and any application requiring matched edge timing.

What are the requirements for unused pins on DS1020S-15/T&R in serial versus parallel mode?

In parallel mode (S=1), unused P1–P7 pins must be tied to VCC or GND - floating inputs are prohibited due to CMOS sensitivity. In serial mode (S=0), P1–P7 become high-impedance and must still be tied to defined logic levels. Pin Q/P0 may float if unused, but D and C must never float and require pull-up/down as needed. These rules apply strictly to DS1020S-15/T&R to prevent erratic behavior or increased ICC.

Does DS1020S-15/T&R support daisy-chaining, and what is required to implement it?

Yes, DS1020S-15/T&R supports daisy-chaining via its serial interface: connect Q of one device to D of the next, with shared C and E lines. Each device requires eight clock cycles per 8-bit load, and the total bit count equals 8 × number of devices. A 1 kΩ–10 kΩ resistor must connect Q of the last device to D of the first for automatic readback restoration. This configuration is validated for DS1020S-15/T&R in Figure 3 of the datasheet.

What is the maximum clock frequency supported by DS1020S-15/T&R's serial interface?

The DS1020S-15/T&R serial interface supports a minimum clock width (tCW) and enable width (tEW) of 50 ns each, corresponding to a maximum clock frequency of 10 MHz. This is specified in the AC Electrical Characteristics table and applies across the full 0°C to 70°C operating range. Exceeding this frequency risks setup/hold violations and unreliable programming of DS1020S-15/T&R delay values.