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 been realized by using a usaul buffer. In a system using dualline power supply, the higher-voltage power supply can 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 dual power supply can not be realized by the system constraint, thans to the input buffer excluding forward diode (in the VDD direction), even 3.3V single power IC can interface to 5V IC.Regarding out put, it is also failsafe designed.