Products: ASIC [Power System Interface]
Development of low-voltage system power supplies continue as part of the trend toward reducing power consumption. However, in case where all of the system components cannot run on a single low-voltage power supply, multiple power supplies are used for the same system. Consequently, many of today's portable electronic devices include a dual (5V / 3.3V) power supplies, each with its own signals.
5V/3.3V Dual Power Supply System
Level Shifter
Since it is often the case with ASICs that several ICs are connected in the same system, such systems are typically required to handle two types of level signals for 3 V and 5 V power. In S1L50000, S1X50000, and S1K50000 series products, the inclusion of two power supplies (such as 3 V and 5 V power supplies) enables the implementation of a bilevel (3 V, 5 V) signal interface for each I/O buffer. Such an interface is best suited for applications that include highspeed signal processing and high drive current capacity.
Gated I/O buffer
The use of the gated input buffer enables input in the Hi-Z state, which has not usually been possible using a buffer. In a system using dualline power supply, the high-voltage power supply may be cut off. Using this function allows hot-plugging a PC card and achieving lower power consumption in the backup mode of PDA.
3.3V Single Power Supply System
Failsafe I/O Buffer
Even when system constraints preclude the implementation of a dual power supply system, it is still possible to provide an interface between a 3 V single power supply chip and a 5 V chip by implementing an input buffer that does not include a forward diode (in the VDD direction), which also provides failsafe support for output.
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