公开(公告)号：CA1177986A

公开(公告)日：1984-11-13

申请号：CA408685

申请日：1982-08-04

Applicant: MOTOROLA INC

Inventor： ZOBEL DON W ,  MAIN W ERIC ,  PACE W DAVID ,  WELTY DENNIS L

IPC: H04B1/58 ,  H04B3/03 ,  H04M19/00 ,  H04M7/00

Abstract: BALANCED CURRENT MULTIPLIER CIRCUIT FOR A SUBSCRIBER LOOP INTERFACE CIRCUIT A balanced multiplier circuit for a subscriber loop interface circuit (SLIC) which provides both loop current to a two-wire bidirectional subscriber loop and suppression of longitudinal signals generated at the two-wire loop input to the SLIC while maintaining the midpoint load voltage at half the available power supply voltage applied to the SLIC.

公开(公告)号：CA1183582A

公开(公告)日：1985-03-05

申请号：CA408031

申请日：1982-07-26

Applicant: MOTOROLA INC

Inventor： ZOBEL DON W ,  PACE WILSON D

IPC: H03K4/50 ,  H03K4/501 ,  H03K4/502 ,  H03K3/36

Abstract: ION DIFFERENTIAL RELAXATION OSCILLATOR CIRCUIT A relaxation oscillator which is suited for fabrication as a monolithic circuit and which uses a parallel resistive capacitive frequency determining network wherein a capacitor is charged and discharged between an upper and lower voltage level. As the capacitor is charged to a potential exceeding a first threshold voltage level supplied to a comparator switch, the operating state of the comparator is caused to switch. A current detecting circuit is included which detects a current that is proportional to the charging current supplied to the capacitor from a charge circuit. As the proportional current decreases in value below a predetermined level due to the capacitor being charged to the upper voltage level the current detecting circuit is disabled which actuates a control circuit for switching the threshld voltage applied to the comparator to a lower level. The actuated control circuit also disables the charge circuit such that the capacitor discharges to the lower voltage level at which time the comparator switches states to disable the control circuit whereby the threshold voltage level is switched to the first level. Thereafter, the charge circuit is enabled to enable the current detecting circuit and to charge the capacitor to the upper voltage level.

公开(公告)号：CA1177985A

公开(公告)日：1984-11-13

申请号：CA408607

申请日：1982-08-03

Applicant: MOTOROLA INC

Inventor： ZOBEL DON W ,  WELTY DENNIS L

IPC: H04B1/58 ,  H04B3/03 ,  H04M19/00 ,  H04Q3/42 ,  H04M7/00

Abstract: ELECTRONIC TERMINATOR CIRCUIT A subscriber loop interface circuit (SLIC) is used as a terminator circuit which is ground referenced for providing signal conversion between a two-wire bidirectional transmission signal path and a pair of two-wire unidirectional transmission signal paths. The SLIC and associated circuitry allows the use of an all electronic circuit to replace bulky transformers generally utilized in telecommunication systems.

公开(公告)号：EP0086811A4

公开(公告)日：1984-11-21

申请号：EP82902606

申请日：1982-07-20

Applicant: MOTOROLA INC

Inventor： ZOBEL DON W ,  PACE W DAVID

IPC: H03K4/50 ,  H03K4/501 ,  H03K4/502

CPC classification number: H03K4/502

公开(公告)号：EP0089350A4

公开(公告)日：1985-06-06

申请号：EP82902779

申请日：1982-08-06

Applicant: MOTOROLA INC

Inventor： ZOBEL DON W ,  WELTY DENNIS L

IPC: H04B1/58 ,  H04B3/03 ,  H04M19/00 ,  H04Q3/42

CPC classification number: H04B1/58 ,  H04M19/005

Abstract: A subscriber loop interface circuit (SLIC)(10) is used in a terminator circuit (100) which is ground referenced for providing signal conversion between a two-wire bidirectional transmission signal path (102, 104) and a pair of two-wire unidirectional transmission signal paths (106, 108). The SLIC and associated circuitry allows the use of an all electronic circuit to replace bulky transformers generally utilized in telecommunication systems.