Low-pin-count OctaBus memory subsystem for IoT & automotive

November 11, 2016 // By Graham Prophet
Non-volatile memory maker Macronix (Hsinchu, Taiwan) has released a 12 pin-count bus interface, a design that keeps the high speed, high efficiency features of OctaFlash and uses only 12 pins, sharing the same data I/O, to enable simplicity in system design and optimize PCB space.

OctaFlash was introduced as the fastest, high-efficiency 8-I/O Serial NOR Flash with 400 MB/sec data transfer rate, in 2015. Increasing demand for “instant-on” and an “interactive graphical user interface, has led Macronix to develop its low pin-count, high-performance OctaBus memory interface. The new bus interface keeps the low pin count feature of OctaFlash and combines both OctaFlash and the new OctaRAM components on a single bus. The two products can share the same data I/O and certain signal control pins and are designed to be compatible with each other with regards to their modified memory protocols. This enables chipset providers to combine PCB layout designs for OctaFlash and OctaRAM or even use a common PCB design.


In the OctaBus memory subsystem, OctaFlash is deployed as a 200 MHz high performance element; while in tandem, OctaRAM enables designers to optimize their system design with significant cost savings through efficient pin sharing. With its design changed from parallel to serial interface, OctaRAM delivers a performance comparable to DDR2 and allows an improved ease of system design.


With its strengths in low pin count and sharing of the I/O bus, OctaBus memory is aimed at the MCP (multi chip package) market. The original design of MCP chips, using separate buses, typically requires a BGA package with 80 pins. A design adopting OctaBus can have the package dimension reduced from 9 x 9 mm to 6 x 8 mm. In particular, an MCP combining OctaBus advantages of OctaFlash and OctaRAM in KGD form (known good die), provides even further simplicity of design and reduced complexity to satisfy system manufacturers’ critical demands of cost reduction and design flexibility.


Macronix’s OctaBus memory subsystem will include three major product lines: Macronix’s own OctaFlash series, an OctaMCP product line and a discrete OctaRAM line provided by other memory ecosystem and supply chain partners.


OctaFlash: 256 Mb to 2 Gb

Package: 24BGA (all), 16SOP (256