Summary

With a reference current source using a depression NMOS transistor, the circuit activates instantly when the power is turned on and generates reference voltage with NMOS bias transistor.

Application

Source of reference voltage to be supplied to the regulating amplifier.

Experience & Performance

Used in low power microcomputers.

Key Elements

Layout wires as GND shielding to output reference voltage while paying attention not to cause crosstalk with other signals. Main transistors have their current running in the same direction to improve the currents precision. Making geometry consistent enhances the characteristics.

Summary

By using power source voltage, the circuit generates constant voltage that is exclusively used for oscillating circuit. Current source of amplifier is supplied by voltage reference generator circuit.

Application

Source of constant voltage supplied to oscillating circuit.

Experience & Performance

Used in low power microcomputers.

Key Elements

Differential pairs of amplifier is located per Common Centroid. Tail current source of amplifier is generated in same direction and shape as that of NMOS transistor of voltage reference generator circuit to improve the current precision.

Summary

Having crystal unit attached, the circuit generates frequency of 32.768 kHz. Generated oscillation can be adjusted by digital control. Voltage source is supplied by constant voltage generator circuit.

Application

Low power RTC

Experience & Performance

Used in low power microcomputer.

Key Elements

Layout wires for gate/drain signals while paying attention not to cause crosstalk with other signals. Avoid laying out signals to be in parallel or crossed manners that may cause opposite phases.

Summary

Detecting power supply voltage down. When power supply voltage has been dropped, it detects immediately and output.

Application

Mobile device which requires battery-powered.

Experience & Performance

Used in low power microcomputer.

Key Elements

Converter differential couple does routing of layout considered direction of flow and circuit patterns.
For preventing accident, dummy friction is allocated around partial pressure friction to stabilized friction per one unit.

Summary

Output voltage at A/D converter is compared based on analog input voltage at a constant frequency by sample-hold circuit. Result are shown by digital code.

Application

Mobile device which requires battery-powered.

Experience & Performance

Installed for low power microcomputers.

Key Elements

Allocate capacitor array for common centroidal relation to minimize variation. Layout wires carefully while parasitic capacitance is weighted.
Dummy capacitance is allocated to minimize errors surround capacitor array. Unit will be stable by this method.