The DS1021 Programmable 8-Bit Silicon Delay Line is an 8-bit user-programmable CMOS silicon integrated circuit. Delay values, programmed using either the 3-wire serial port or the 8-bit parallel port, can be varied over 256 equal steps.
The DS1021 programmable 8‑bit silicon delay line provides precise timing adjustments in 256 steps. Two versions are available: the DS1021‑25 with 0.25 ns steps (max 73.75 ns) and the DS1021‑50 with 0.5 ns steps (max 137.5 ns). The device is TTL/CMOS‑compatible, low‑power, and comes in an auto‑insertable 16‑pin SOIC package.
Programming can be performed via a 3‑wire serial interface or an 8‑bit parallel port. In parallel mode the eight P0‑P7 pins set the delay directly, while serial mode shifts an 8‑bit value into the device. Daisy‑chaining of multiple devices is supported, and detailed timing parameters such as setup/hold times, clock frequency (10 MHz), and enable widths are specified in the datasheet.
| Supply voltage VCC (typical) | 5.0 V |
|---|---|
| High‑level input voltage VIH | 2.2 V |
| Clock frequency | 10 MHz |
| Enable width tEW | 50 ns |
| Maximum output current (Q pin) | 4 mA |
The DS1021 can be programmed using either a 3‑wire serial port or an 8‑bit parallel port.
The device operates with a supply voltage between 4.75 V and 5.25 V (typical 5.0 V).
Yes, devices can be cascaded by connecting the serial output of one to the serial input of the next.