公开(公告)号：JPH0229049A

公开(公告)日：1990-01-31

申请号：JP1300489

申请日：1989-01-20

Applicant: ADVANCED MICRO DEVICES INC

Inventor： JIEFURII EMIIRU BUREEMAA ,  JIYOO UIRIAMU PIITAASON

IPC: H04L25/02 ,  H03F3/30 ,  H03F3/72 ,  H03K17/08 ,  H03K17/082 ,  H03K17/16 ,  H03M5/16 ,  H04L25/08 ,  H04L25/49

Abstract: PURPOSE: To satisfy the necessary conditions for an output impedance, an output response and the current limit by using a ternary code transmitter including a current source amplifier and the 1st and 2nd voltage source amplifiers. CONSTITUTION: A transmitter circuit 7 consists of a complete differential voltage source amplifier which converts a binary digital signal into a pseudo ternary (3-level) code via the external output pins LOUT1 and LOUT2. The pins LOUT1 and LOUT2 are connected to a twist pair transmission line via an S interface. A current source amplifier 10 functions to decide the maximum drive current that is allowed in the voltage source amplifiers 12 and 14. The amplifiers 12 and 14 function to control the current value that is needed for driving both pins LOUT1 and LOUT2 at the reference voltage VREFT. In such a constitution, the limited current value is supplied in a load state of 5.6Ω and the ringing is reduced on the transmission line.

公开(公告)号：JPH02294142A

公开(公告)日：1990-12-05

申请号：JP8059290

申请日：1990-03-28

Applicant: ADVANCED MICRO DEVICES INC

Inventor： DEIIN GURAMUROOZU ,  JIYOO UIRIAMU PIITAASON

IPC: H04M1/00 ,  G06F1/32 ,  G06F13/24 ,  H04L29/08 ,  H04L29/12 ,  H04M1/253

Abstract: PURPOSE: To reduce power consumption by making a peripheral device speed up a clock signal to a microprocessor automatically when the peripheral device detects an event requiring service. CONSTITUTION: A microprocessor 10 reads in and writes in data to a peripheral device 12 including a clock divider 20 which is under the control of the peripheral device 12 as well as the microprocessor 10. The peripheral device 12 at the same time when an interruption to the microprocessor 10 occurs, for example, when a packet arrives from a central station, increases the speed of a clock to the microprocessor 10. The microprocessor uses the high-speed clock signal to process packets and instructs the peripheral device 12 to decrease the frequency to the lower than that of the clock so that electric power is not consumed thereafter. Consequently, the power consumption can be reduced.