Skew corner driver compensation

Patent metadata

Field	Value
Publication number	US-12587190-B2
Application number	US-202318455436-A
Country	US
Kind code	B2
Filing date	Aug 24, 2023
Priority date	Aug 24, 2023
Publication date	Mar 24, 2026
Grant date	Mar 24, 2026

Abstract

Systems and methods for skew compensation in a push-pull driver are described. A device can include a first circuit configured to output a skew measurement of an output driver stage in a driver circuit. The device can further include a second circuit configured to determine a first skew parameter based on the skew measurement and apply a first bias that is dependent on the skew measurement to drive a high-side transistor in the output driver stage. The device can further include a third circuit configured to determine a second skew parameter based on the skew measurement and apply a second bias that is dependent on the skew measurement to drive a low-side transistor in the output driver stage. The first bias and the second bias can be complementary.

First claim

What is claimed is:

1 . A semiconductor device comprising:
a first circuit configured to output a skew measurement of an output driver stage in a driver circuit; a second circuit configured to:
determine a first skew parameter based on the skew measurement; and
apply a first bias that is dependent on the skew measurement to drive a high-side transistor in the output driver stage; and
a third circuit configured to:
determine a second skew parameter based on the skew measurement; and
apply a second bias that is dependent on the skew measurement to drive a low-side transistor in the output driver stage, wherein the first bias and the second bias are complementary,
wherein:
the first circuit comprises a replica of the high-side transistor and a replica of the low-side transistor; and
the skew measurement indicates an imbalance between the replica of the high-side transistor and the replica of the low-side transistor.

2 . The semiconductor device of claim 1 , wherein:
the first circuit comprises a current mirror formed by at least a replica of the high-side transistor and a replica of the low-side transistor; and the skew measurement represents an output current of the current mirror.

3 . The semiconductor device of claim 1 , further comprising:
a first pre-driver configured to drive the high-side transistor; a second pre-driver configured to drive the low-side transistor; the second circuit is configured to apply the first bias to the first pre-driver; and the third circuit is configured to apply the second bias to the second pre-driver.

4 . The semiconductor device of claim 3 , wherein:
the first pre-driver is a first current mode pre-driver; a second pre-driver is a second current mode pre-driver; the first bias is a first bias current; the second bias is a second bias current; the second circuit is configured to apply the first bias current to adjust a current source of the first current mode pre-driver; and the third circuit is configured to apply the second bias current to adjust a current source of the second current mode pre-driver.

5 . The semiconductor device of claim 3 , wherein:
the first pre-driver is a first voltage mode pre-driver; a second pre-driver is a second voltage mode pre-driver; the first bias is a first bias voltage; the second bias is a second bias voltage; the second circuit is configured to apply the first bias voltage to adjust a drive voltage being outputted by the first voltage mode pre-driver; and the third circuit is configured to apply the second bias voltage to adjust a drive voltage being outputted by the second voltage mode pre-driver.

6 . The semiconductor device of claim 1 , wherein the drive circuit is a push-pull driver.

7 . An apparatus comprising:
a controller configured to receive an input signal; an output driver stage comprising a high-side transistor and a low-side transistor, the output driver stage being configured to switch the high-side transistor and the low-side transistor to output an output voltage that represents the input signal; and a circuit configured to:
determine a skew measurement of the output driver stage;
determine a first skew parameter based on the skew measurement;
apply a first bias that is dependent on the skew measurement to drive the high-side transistor;
determine a second skew parameter based on the skew measurement; and
apply a second bias that is dependent on the skew measurement to drive the low-side transistor, wherein the first bias and the second bias are complementary,
wherein:
the circuit comprises a replica of the high-side transistor and a replica of the low- side transistor; and
the skew measurement indicates an imbalance between the replica of the high-side transistor and the replica of the low-side transistor.

8 . The apparatus of claim 7 , wherein:
the circuit comprises a current mirror formed by at least a replica of the high-side transistor and a replica of the low-side transistor; and the skew measurement represents an output current of the current mirror.

9 . The apparatus of claim 7 , further comprising:
a first pre-driver configured to drive the high-side transistor; a second pre-driver configured to drive the low-side transistor, wherein the circuit is configured to:
apply the first bias to the first pre-driver; and
apply the second bias to the second pre-driver.

10 . The apparatus of claim 9 , wherein:
the first pre-driver is a first current mode pre-driver configured to drive the high-side transistor; a second pre-driver is a second current mode pre-driver configured to drive the low-side transistor; the first bias is a first bias current; the second bias is a second bias current; and the circuit is configured to:
apply the first bias current to adjust a current source of the first current mode pre-driver; and
apply the second bias current to adjust a current source of the second current mode pre-driver.

11 . The apparatus of claim 9 , wherein:
the first pre-driver is a first voltage mode pre-driver configured to drive the high-side transistor; a second pre-driver is a second voltage mode pre-driver configured to drive the low-side transistor; the first bias is a first bias voltage; the second bias is a second bias voltage; and the circuit is configured to:
apply the first bias voltage to adjust a drive voltage being outputted by the first voltage mode pre-driver; and
apply the second bias voltage to adjust a drive voltage being outputted by the second voltage mode pre-driver.

12 . The apparatus of claim 7 , wherein the controller, the output driver stage and the circuit are parts of a push-pull driver.

13 . A method for operating a driver circuit, the method comprising:
determining a skew measurement of an output driver stage of a driver circuit; determining a first skew parameter based on the skew measurement; applying a first bias that is dependent on the skew measurement to drive a high-side transistor of the output driver stage; determining a second skew parameter based on the skew measurement; and applying a second bias that is dependent on the skew measurement to drive a low-side transistor of the output driver stage, wherein:
the first bias and the second bias are complementary; and
the skew measurement indicates an imbalance between a replica of the high-side transistor and a replica of the low-side transistor.

14 . The method of claim 13 , wherein determining the skew measurement comprises:
applying reference current to a current mirror formed by at least a replica of the high-side transistor and a replica of the low-side transistor; and obtaining an output of the current mirror that represents the skew measurement.

15 . The method of claim 13 , further comprising:
applying the first bias to a first pre-driver configured to drive the high-side transistor; and applying the second bias to a second pre-driver configured to drive the low-side transistor.

16 . The method of claim 13 , wherein:
applying the first bias comprises applying a first bias current to adjust a current source of a first current mode pre-driver configured to drive the high-side transistor; and applying the second bias comprises applying a second bias current to adjust a current source of a second current mode pre-driver configured to drive the low-side transistor.

17 . The method of claim 13 , wherein:
applying the first bias comprises applying a first bias voltage to adjust a drive voltage being outputted by a first current mode pre-driv

Assignees

• Renesas Electronics America Inc

Inventors

• Finn Steven Ernest
• Sluder Preston Blaire

Classifications

• H03K17/063

  in field-effect transistor switches · CPC title

• H03K2217/0063

  High side switches, i.e. the higher potential [DC] or life wire [AC] being directly connected to the switch and not via the load · CPC title

• H03K2217/0072

  Low side switches, i.e. the lower potential [DC] or neutral wire [AC] being directly connected to the switch and not via the load · CPC title

• H03K19/00315

  in field-effect transistor circuits · CPC title

• H03K2217/0081

  Power supply means, e.g. to the switch driver · CPC title