Bitserial

Bitserial is a term used to describe systems in which data is represented, transmitted, or processed one bit at a time rather than in wide words. It covers both serial communication links that send individual bits per clock cycle and computational architectures that implement arithmetic and logical operations with a 1-bit datapath across many clock cycles. Bitserial designs emphasize simplicity and resource efficiency over raw throughput.

In bit-serial processors, the datapath is typically 1 bit wide. A single-bit ALU, registers, and a shift register feed each successive bit through the computation. Complex operations such as addition or multiplication are implemented over many cycles. The approach yields small area and low power, attractive for very small low-cost devices and for FPGA/ASIC blocks where high speed is not required.

In serial communication, bit-serial interfaces transmit one bit per clock. Asynchronous protocols (such as UART) and synchronous bit-serial links are simple and require few pins, but they offer lower data rates and higher latency compared with parallel or wider serial interfaces. Bit-serial links are common in embedded systems and interconnects where simplicity and long wire lengths are important.

Trade-offs: Bit-serial designs trade lower throughput for reduced silicon area, simpler timing, and easier scaling to larger numbers of bits. They are still used in education, research, and certain application niches such as ultra-low-power sensors, cryptographic accelerators, and bit-serial components within larger systems.