US 5,471,524 A · Toll call restrictor method and apparatus

A device for controlling telephone dialing access, the device having a pair of central office telephone line input terminals for connection to a telephone line from a central office and a pair of telephone line output terminals connected to the central office telephone line input terminals via a telephone dialing control circuit, the circuit comprising:

a diode bridge circuit having a first input connected to a first one of the telephone line output terminals and a second input connected to a first one of the central office line input terminals;
a power disconnect circuit electrically connected to the diode bridge, all power for circuits within the device being provided via the power disconnect circuit when the power disconnect circuit is actuated to a first state and no power being provided via the power disconnect circuit when the power disconnect circuit is actuated to a second state;
a voltage protection zener diode connected electrically between the power control disconnect circuit and package ground;
a DTMF decoder integrated circuit chip electrically connected to a second one of the telephone line output terminals and a second one of the central office line input terminals for receiving tones output by a local telephone as a number is dialed, the DTMF decoder chip receiving its power via the power disconnect control circuit;
a microprocessor integrated circuit chip receiving decoded inputs from the DTMF decoder chip so that numbers dialed can be used to input program steps or data in the microprocessor, the microprocessor receiving its power via the power disconnect circuit, an output from the microprocessor being electrically connected to the power disconnect circuit to actuate the power disconnect circuit to the first or second states;
a standby power circuit connected to maintain power to the microprocessor when the power disconnect circuit is actuated to the second state;
a disconnect timer circuit electrically connected to the power disconnect circuit and to an input of the microprocessor and inputting a signal to the microprocessor at a selected time after the microprocessor has sent a signal output to stop power from being supplied by the power disconnect circuit to itself and other integrated circuits on the chip so that the microprocessor automatically outputs a signal to the power disconnect circuit to resupply power to itself and other integrated circuits on the chip through the power disconnect circuit a selected time after the microprocessor outputs a signal to disconnect power to itself and other integrated circuits on the chip, the selected time being adequate to indicate to the central office the local telephone is not connected to the telephone line from the central office, the resupply power signal being sent prior to all power being completely removed from the microprocessor such that the microprocessor maintains the input program steps as data during the time power from the power disconnect circuit is disconnected from the microprocessor;
and
a phone number memory chip electrically connected to the microprocessor and storing telephone numbers or data under the control of the microprocessor.

6 more elements

The method of programming a dialing control circuit comprising:

decoding a DTMF signal entered from a local telephone;
determining if the number entered matches the selected security code, said security code having fewer digits than that required to complete a phone call through the central office telephone line;
disconnecting the local telephone from the central office telephone line after the security code has been properly entered and recognized;
automatically reconnecting the local telephone line to the central office phone line at a selected time after the disconnection between the local telephone and the central office phone line has occurred, the selected time being sufficiently long that the central office system registers that the local telephone has been completely disconnected and hung up, the reconnection of the local telephone to the central office telephone lines resulting in a new dial tone being obtained;
permitting the dialing of a toll call after the dial tone has been re-obtained following the disconnection after the security code was entered;
permitting, alternatively, the programming of the dialing control circuit by entering programming digits into the local telephone, each permissible programming sequence being selected to ensure that a disconnection between the local telephone and the central office telephone lines occurs on a regular basis and in each event prior to the central office system recognizing the numbers input as being a potential number and attempting to connect the local telephone to a number which is perceived to have been dialed;
upon entry from the local telephone of an end of step signal, disconnecting the local telephone from the central office telephone line;
and
automatically reconnecting the local telephone line to the central office phone line at a second selected time after the disconnection between the local telephone and the central office phone line has occurred, the second selected time being sufficiently long that the central office system registers that the local telephone has been completely disconnected and hung up, the reconnection of the local telephone to the central office telephone lines resulting in a new dial tone being obtained.

6 more elements

Toll call restrictor method and apparatus

Life of this patent

Toll call restrictor method and apparatus

Life of this patent

Abstract

Claims17