Abstract: Provided is an on-chip reference current generating circuit for generating a reference voltage that can be digitally calibrated and is substantially not affected by changes in temperature and/or supply voltage. The on-chip reference current generating circuit includes a summing circuit for receiving a first current having a negative temperature coefficient and a second current having a positive temperature coefficient, and outputting a third current based upon, is a sum of, the first and second currents; and a digital calibration circuit for calibrating the third current to be the reference current in response to a digital control signal. Using the on-chip reference current generating circuit, it is possible to precisely and digitally calibrate an offset between currents due to a change in temperature and/or supply voltage.

Abstract: Provided is an on-chip reference current generating circuit for generating a reference voltage that can be digitally calibrated and is substantially not affected by changes in temperature and/or supply voltage. The on-chip reference current generating circuit includes a summing circuit for receiving a first current having a negative temperature coefficient and a second current having a positive temperature coefficient, and outputting a third current based upon, is a sum of, the first and second currents; and a digital calibration circuit for calibrating the third current to be the reference current in response to a digital control signal. Using the on-chip reference current generating circuit, it is possible to precisely and digitally calibrate an offset between currents due to a change in temperature and/or supply voltage.

Abstract: An external data read/write circuit has a jack including serial clocks, serial data, bus stop, and power source lines installed on a television set and an external service card for writing corresponding area information into a memory of the television via a serial data line when an information transmission key input and a corresponding area code are received from the external service card, and for reading out information required for fault diagnosis from the television when a fault diagnosis key input is received to display the result on a display apparatus of the external service card, thereby writing information needed by a user into a memory or integrated circuit within the television and reading out fault information of the television.