Why IC designers need custom ESD cells
Most foundries running mainstream CMOS processes have a whole set of ESD protection clamps available. In these processes some of the conventional ESD approaches are still effective. There is also typical a full General Purpose I/O (GPIO) library available for free with ESD cells integrated.
However for novel applications, the IC designer can be constrained by the GPIO library. It could be that the parasitic capacitance of the integrated ESD protection clamps is excessive for high bandwidth interfaces (wired, wireless or optical). Or the leakage current of traditional ESD clamps prevents low-power applications like IoT or medical. Many applications also require much higher ESD robustness.
Sofics IP for Mainstream CMOS
Process technology covered
TSMC 65nm / 55nm
GlobalFoundries (IBM) 130nm
GlobalFoundries (Chartered) 65nm
Tower Semi 130nm
XFab (Altis) 130nm
Several proprietary IDM fabs
Key focus areas
Beyond standard voltage levels
Sofics IP is used in high bandwidth communication interfaces networks. These interfaces need ESD clamps with low parasitic capacitance. Sofics clamps provide standard ESD robustness and do not require a resistance in the signal path.
Our IP was used for sensor interfaces, battery connections and more. We have delivered solutions for high voltage tolerance (5V or higher) thanks to a flexible but deterministic solution set.
Battery powered applications
Customers have integrated Sofics ESD in IoT systems. The leakage of our ESD cells is 100x lower compared to conventional approach. Huge improvements can be made in stand-by, sleep, operational modes and during power-cycles. Sofics has solutions available for interfaces and rail clamps.
Automotive applications typically require higher ESD robustness levels. Sofics ESD technology can be easily scaled to reach higher HBM and CDM protection levels. In some cases the on-chip ESD cells are adapted to sustain contact discharge 8kV IEC 61000-4-2.
Radiation hard and cold-spare
Integrated circuits used in space, nuclear physics research or several medical applications require a higher tolerance against radiation. The conventional I/O circuits and ESD devices degrade under this kind of stress. Fortunately, Sofics has proven solutions.
IC products from our customers
Our customers have created amazing products even on mainstream CMOS technology. Examples include high-speed interfaces for consumer, datacenter applications, wireless IoT, bluetooth, wifi circuits, low-power Internet of Things devices and TCON (Timing controller) chips in flat panel displays. Several of our IDM customers have used Sofics IP for Display Drivers for these same displays. The mainstream CMOS processes on several foundries have been used for SIM/smartcard chips. A higher ESD robustness is required for those chips.
Blog article “5 reasons why IoT chips need custom ESD“
Press release about our cooperation with Tower Semi
Press release about our clipping circuit
Press release about our IP delivery to DecaWave (Qorvo now)
Press release about our cooperation with StarChip
Press release about our partnership with UMC
Press release about our IP delivery to RedMere
Press release about our project with Actel FPGA (now Microchip)