Electro-static discharge protection for integrated circuits

Patent metadata

Field	Value
Publication number	US-9608437-B2
Application number	US-201314024833-A
Country	US
Kind code	B2
Filing date	Sep 12, 2013
Priority date	Sep 12, 2013
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

Techniques for improving electro-static discharge (ESD) performance in integrated circuits (IC's). In an aspect, one or more protective diodes are provided between various nodes of the IC. For example, protective diode(s) may be provided between the drain and gate of an amplifier input transistor, and/or between the drain and ground, etc. In certain exemplary embodiments, the amplifier may be a cascode amplifier. Further aspects for effectively dealing with ESD phenomena are described.

First claim

The invention claimed is:

1. An apparatus comprising:
an amplifier comprising an input transistor;
a cascode transistor coupled to a drain of the input transistor;
a first electrical path coupling a gate of the input transistor to the drain of the input transistor; and
a second electrical path that includes a diode, the second electrical path coupling the gate of the input transistor to the drain of the input transistor, the second electrical path in parallel with the first electrical path, the input transistor excluded from the first electrical path and the second electrical path.

2. The apparatus of claim 1 , the diode configured to be forward-biased when a gate-to-drain voltage is positive.

3. The apparatus of claim 1 , the diode configured to be forward-biased when a drain-to-gate voltage of the input transistor is positive.

4. The apparatus of claim 3 , further comprising a third electrical path coupling the gate of the input transistor to the drain of the input transistor, the third electrical path in parallel with the first electrical path and the second electrical path, the input transistor independent from the third electrical path, the third electrical path including a second diode configured to be forward-biased when a gate-to-drain voltage is positive.

5. The apparatus of claim 3 , further comprising a second diode coupling a source of the input transistor to the gate of the input transistor, the second diode configured to be forward-biased when a source-to-gate voltage is positive.

6. The apparatus of claim 1 , wherein the second electrical path further includes a second diode coupled in series with the diode, and wherein the second diode is coupled between the diode and the gate.

7. The apparatus of claim 1 , the amplifier further comprising a cascode transistor, wherein the cascode transistor is independent from the second electrical path, and wherein the diode is configured to be forward-biased when a gate-to-drain voltage of the input transistor is positive.

8. The apparatus of claim 1 , the amplifier further comprising a cascode transistor, and the second electrical path including a resistor coupled in series with the diode.

9. An apparatus comprising:
an amplifier comprising an input transistor;
a first electrical path coupling a gate of the input transistor to a drain of the input transistor;
a second electrical path that includes a diode, the second electrical path coupling the gate of the input transistor to the drain of the input transistor, the second electrical path in parallel with the first electrical path, the input transistor excluded from the first electrical path and the second electrical path; and
a first integrated circuit pad and a second integrated circuit pad, wherein the first integrated circuit pad is coupled to the gate of the input transistor, and the second integrated circuit pad is coupled to a source of the input transistor.

10. An apparatus comprising:
an amplifier comprising an input transistor;
a first electrical path coupling a gate of the input transistor to a drain of the input transistor;
a second electrical path that includes a diode, the second electrical path coupling the gate of the input transistor to the drain of the input transistor, the second electrical path in parallel with the first electrical path, the input transistor excluded from the first electrical path and the second electrical path; and
a resistor coupled in series with the diode, wherein the second electrical path includes the resistor.

11. An apparatus comprising:
an amplifier comprising an input transistor;
a first electrical path coupling a gate of the input transistor to a drain of the input transistor;
a second electrical path that includes a diode, the second electrical path coupling the gate of the input transistor to the drain of the input transistor, the second electrical path in parallel with the first electrical path, the input transistor excluded from the first electrical path and the second electrical path; and
two diodes coupling the drain of the input transistor to a ground terminal.

12. An apparatus comprising:
means for amplifying an input signal;
means for enabling current flow along a first path between a gate of the means for amplifying and a drain of the means for amplifying;
means for enabling current flow along a second path between the gate of the means for amplifying and the drain of the means for amplifying, the second path in parallel with the first path, the means for amplifying excluded from the first path and the second path, the second path including a diode;
means for receiving a first external signal coupled to the gate of the means for amplifying; and
means for receiving a second external signal coupled to a source of the means for amplifying.

13. The apparatus of claim 12 , further comprising second means for amplifying an output of the means for amplifying, wherein the second means for amplifying is independent from the means for enabling current flow along the second path, and wherein the diode is configured to be forward-biased when a gate-to-drain voltage of the means for amplifying is positive.

14. The apparatus of claim 12 , further comprising second means for amplifying an output of the means for amplifying, wherein the second means for amplifying is independent from the means for enabling current flow along the second path, and wherein the means for enabling current flow along the second path includes a resistor coupled in series with the diode.

15. The apparatus of claim 12 , further comprising means for enabling current to flow along a third path from the drain of the means for amplifying to ground.

16. The apparatus of claim 15 , the means for enabling current to flow along the third path including multiple diodes.

17. An apparatus comprising:
an amplifier including a transistor;
a cascode transistor coupled to a drain of the transistor;
a first diode coupled to the drain;
a second diode coupling the first diode to ground, the first diode and the second diode configured to be forward-biased from the drain to a ground terminal; and
a third diode coupled to a gate of the transistor and the drain.

18. The apparatus of claim 17 , further comprising:
a first electrical path coupling a gate of the transistor to the drain of the transistor; and
a second electrical path coupling the drain of the transistor to the ground terminal, the transistor independent of the first electrical path and the second electrical path, the second electrical path including the first diode and the second diode.

19. The apparatus of claim 18 , further comprising a third electrical path coupling the gate of the transistor to the drain of the transistor, the third electrical path in parallel with the first electrical path, the transistor independent of the third electrical path, the third electrical path including a third diode and a resistor, the third diode configured to be forward-biased when a gate-to-drain voltage of the transistor is positive, and wherein the third diode is coupled in series with the resistor.

20. The apparatus of claim 17 , the third diode configured to be forward-biased when a gate-to-drain voltage is positive.

21. An apparatus comprising:
an amplifier comprising an input transistor;
a diode coupling a gate of the input transistor to a drain of the input transistor;
a cascode transistor coupled to the drain of the input transistor; and
a resistor coupled in series with the diode, the resistor further cou

Assignees

• Qualcomm Inc

Inventors

• Youssef Ahmed Abdel Monem
• Gudem Prasad Srinivasa Siva
• Chang Li-Chung
• Abdel Ghany Ehab Ahmed Sobhy

Classifications

• H03F2200/429

  Two or more amplifiers or one amplifier with filters for different frequency bands are coupled in parallel at the input or output · CPC title

• H03F2200/336

  A I/Q, i.e. phase quadrature, modulator or demodulator being used in an amplifying circuit · CPC title

• H03F2200/444

  Diode used as protection means in an amplifier, e.g. as a limiter or as a switch · CPC title

• H03F2200/441

  Protection of an amplifier being implemented by clamping means · CPC title

• H03F1/523

  for amplifiers using field-effect devices (H03F1/526 takes precedence) · CPC title