Profile: Data Delay Devices, Inc. is a designer, developer and manufacturer of analog & digital delay lines, as well as delay line application modules & filters. Our products include digitally programmable pulse generators, dynamic memory timers, gated oscillators and pulse controllers. The 3D3521 is a monolithic CMOS encoder that samples the data input at the rising edge of the input clock. The FDU-2 frequency doubling unit is auto-insertable and requires no external components.