Pulldown devices

Patent metadata

Field	Value
Publication number	US-11260657-B2
Application number	US-201916768066-A
Country	US
Kind code	B2
Filing date	Feb 6, 2019
Priority date	Feb 6, 2019
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

An integrated circuit to drive a plurality of fluid actuation devices includes a contact pad and a programmable pulldown device. The programmable pulldown device is electrically coupled to the contact pad. The programmable pulldown device is settable to any one of a plurality of resistances.

First claim

The invention claimed is:

1. An integrated circuit to drive a plurality of fluid actuation devices, the integrated circuit comprising:
an external contact pad; and
a programmable pulldown device electrically coupled to the external contact pad, the programmable pulldown device comprising an enable signal path, and the programmable pulldown device settable to any one of a plurality of resistances,
wherein the programmable pulldown device is enabled or disabled in response to an enable signal on the enable signal path.

2. The integrated circuit of claim 1 , wherein the programmable pulldown device comprises a transistor to enable the programmable pulldown device in response to the enable signal.

3. The integrated circuit of claim 1 , wherein the programmable pulldown device comprises a voltage bias generator to provide a bias voltage in response to a bias magnitude, the bias voltage to set the programmable pulldown device to one of the plurality of resistances.

4. The integrated circuit of claim 1 , wherein the programmable pulldown device comprises a first transistor settable to provide one of the plurality of resistances in response to a bias voltage and a second transistor to enable the programmable pulldown device in response to the enable signal.

5. The integrated circuit of claim 1 , wherein the integrated circuit is a fluid ejection die.

6. An integrated circuit to drive a plurality of fluid actuation devices, the integrated circuit comprising:
a first contact pad;
a programmable pulldown device electrically coupled to the first contact pad; and
a configuration register,
wherein a resistance of the programmable pulldown device is set based on data stored in the configuration register.

7. The integrated circuit of claim 6 , wherein the programmable pulldown device is enabled based on data stored in the configuration register.

8. The integrated circuit of claim 6 , further comprising:
a plurality of contact pads comprising the first contact pad, a second contact pad, and a third contact pad; and
control logic to enable the programmable pulldown device in response to both a logic low signal on the second contact pad and a logic low signal on the third contact pad.

9. The integrated circuit of claim 6 , wherein the programmable pulldown device comprises a first transistor to produce a resistance based on a bias voltage and a second transistor electrically coupled to the first transistor to enable the programmable pulldown device in response to an enable signal.

10. The integrated circuit of claim 9 , wherein the programmable pulldown device comprises a voltage bias generator to provide the bias voltage to a gate of the first transistor in response to a bias magnitude stored in the configuration register.

11. The integrated circuit of claim 10 , wherein the bias magnitude comprises a multi-bit value.

12. The integrated circuit of claim 9 , wherein the first transistor is to produce a resistance between 30 kOhms and 300 kOhms.

13. The integrated circuit of claim 6 , further comprising:
an electrostatic discharge circuit coupled to the first contact pad.

14. An integrated circuit to drive a plurality of fluid actuation devices, the integrated circuit comprising:
a contact pad;
a programmable pulldown device electrically coupled to the contact pad; and
a static pulldown device electrically coupled to the contact pad, the static pulldown device comprising an enable signal path,
wherein the static pulldown device is enabled or disabled in response to an enable signal on the enable signal path.

15. The integrated circuit of claim 14 , further comprising:
a configuration register,
wherein a resistance of the programmable pulldown device is set based on data stored in the configuration register.

16. An integrated circuit to drive a plurality of fluid actuation devices, the integrated circuit comprising:
a contact pad;
a programmable pulldown device electrically coupled to the contact pad;
a static pulldown device electrically coupled to the contact pad; and
a configuration register,
wherein a resistance of the programmable pulldown device is set based on data stored in the configuration register, and
wherein the programmable pulldown device comprises a first transistor to produce a resistance based on a bias voltage, a second transistor electrically coupled to the first transistor to enable the programmable pulldown device in response to an enable bit stored in the configuration register, and a voltage bias generator to provide the bias voltage to a gate of the first transistor in response to a bias magnitude stored in the configuration register.

Assignees

• Hewlett Packard Development Co

Inventors

• Gardner James Michael
• Linn Scott A
• Corrigan George H

Classifications

• B41J2/04511

  for electrostatic discharge protection · CPC title

• B41J2/0458 Primary

  controlling heads based on heating elements forming bubbles · CPC title

• B41J2/1753

  Details of contacts on the cartridge, e.g. protection of contacts · CPC title

• H03K19/017581

  programmable · CPC title

• B41J2/04541

  Specific driving circuit · CPC title