Variable Power Supply Output Voltage by Micro Processing Unit Upgrade Card
Original Publication Date: 1995-Jul-01
Included in the Prior Art Database: 2005-Mar-30
Disclosed is a power supply which can change its output voltage according to the Micro Processing Unit (MPU) card.
Variable Power Supply Output Voltage by Micro Processing
a power supply which can change its output voltage
according to the Micro Processing Unit (MPU) card.
upgrade is very popular. When an MPU card
upgraded, sometimes the required voltage for the MPU also changes
accordingly. In the past, the power supply card also have to be
changed along with the upgraded MPU card.
invention, the power supply card can be used as is
because it changes its output voltage for MPU.
shows the circuit that implement the subject
invention. The DC/DC converter for MPU VCC is composed of the
coil (L1), the switching device(FET1), the diode (D1), the
capacitor (C1), the regulator IC and the feedback resistors (R1, R2
R3). The feedback voltage for MPU VCC is generated by the feedback
resistors R1, R2 and R3 where R3 is in the MPU card. The feedback
resistors R1 and R2 are decided when the DC/DC converter card is
designed. Therefore, MPU VCC for the upgrade MPU can be set by R3
voluntarily. In the figure, R3 is assembled between MPU VCC and the
feedback signal line. This case is to lower MPU VCC for the upgraded
MPU. If R3 is assembled between the feedback signal and GND, MPU VCC
will be set higher.