Bipolar junction transistor heater circuit
AssigneeAnalog Devices International Unlimited Company
InventorsAref Kahaei, James Vincent Sousae, Carl T. Nelson, Robert Dobkin
Life of this patent
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Abstract
An integrated circuit (IC) heater circuit comprises a drive circuit configured to increase the temperature of the IC when consuming power; a temperature sensor coupled to a control node of the drive circuit to activate and deactivate the drive circuit to provide an ambient temperature for the IC, wherein current of the temperature sensor varies with temperature; and a control circuit coupled to the temperature sensor and configured to adjust variation in the temperature sensitivity of the current of the temperature sensor.
Claims17
A method of operating an integrated circuit (IC) heater circuit, the method comprising:
- consuming power using a drive circuit of the IC;
- activating and deactivating the drive circuit using a temperature sensor included in the IC to control temperature of the IC, wherein deactivating the drive circuit includes providing a pull down current to a control node of the drive circuit using a bipolar junction transistor (BJT) included in the temperature sensor circuit, and the pull down current of the BJT varies with temperature;
- and
- adjusting the variation in temperature sensitivity of the current of the temperature sensor including forcing a bias voltage at a base region of the BJT to vary with temperature inversely with the pull down current of the BJT using the control circuit.
A method of operating an integrated circuit (IC) heater circuit, the method comprising:
- consuming power using a drive circuit of the IC;
- activating and deactivating the drive circuit using a temperature sensor included in the IC to control temperature of the IC, wherein current of the temperature sensor varies with temperature;
- providing a pull down current to a control node of the drive circuit using a bipolar junction transistor (BJT), wherein a size of the BJT determines a set temperature of the IC and the activating and deactivating the drive circuit sets ambient temperature of the IC to the set temperature;
- and
- adjusting variation in temperature sensitivity of the current of the temperature sensor using a control circuit included in the IC.
An integrated circuit (IC) temperature setting circuit, the IC temperature setting circuit comprising:
- a drive circuit to consume power when activated;
- a temperature sensor configured to activate and deactivate the drive circuit to set the IC to an operating set temperature, wherein the temperature sensor includes a bipolar junction transistor (BJT) configured to provide a pull down current to a control node of the drive circuit to deactivate the drive circuit, wherein the pull down current of the BJT varies with temperature;
- and
- a control circuit configured to force a bias voltage at a base region of the BJT to vary with temperature inversely with the pull down current of the BJT.
Dependencies are inferred from the claim text.