WO2010088179A1

WO2010088179A1 - Configurable push-pull driver

Info

Publication number: WO2010088179A1
Application number: PCT/US2010/021954
Authority: WO
Inventors: Mauricio E. Hernandez-Distancia; Peter Narbus
Original assignee: Continental Automotive Systems US Inc; Continental Automotive Systems Inc
Current assignee: Continental Automotive Systems Inc
Priority date: 2009-01-29
Filing date: 2010-01-25
Publication date: 2010-08-05
Anticipated expiration: 2011-07-29

Abstract

A configurable push-pull driver uses two controllers and two switches, with each controller controlling one of the switches. The controllers are each capable of operating the push-pull driver in a default push-pull mode or in a second low-side pull mode.

Description

CONFIGURABLE PUSH-PULL DRIVER

PRIORITY STATEMENT

[0001] The application claims priority to U.S. Provisional Application No. 61/148,198 which was filed on January 29, 2009.

BACKGROUND

[0002] The present disclosure is directed toward an integrated circuit push-pull driver which is capable of operating in a low-side pull mode or a push-pull mode.

[0003] In many fields of manufacture, and particularly in the automotive field, it is necessary to use electrical controllers which are capable of producing electrical outputs that are forced to either a positive voltage or a zero voltage. Alternately certain applications require an electrical output which is passively at a high voltage, but can be forced to OV. By way of example, a diesel engine requires an alternating electrical signal which is passively a positive voltage (high) but can be forced to no voltage (low). In a similar manner a gasoline engine requires an electrical signal which can be forced to either high voltage or a low voltage, but is passively electrically disconnected. A device which passively outputs a high voltage but can be pulled to OV is referred to as a "low-side pull driver." A device which can actively force a high voltage and a low voltage, but by default is passively electrically disconnected is referred to as a "push-pull driver." SUMMARY

[0004] Disclosed is a push-pull driver which has a push controller and a pull controller. The push-pull driver also has a first and a second switch. The first switch is controllably coupled to the push driver, and the second switch is controllably coupled to the pull driver.

[0005] These and other features can be best understood from the following specification and drawings, the following of which is a brief description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 illustrates an example push-pull driver.

[0007] Figure 2 illustrates an example low-side pull driver.

[0008] Figure 3 is a schematic view of an example power train controller.

DETAILED DESCRIPTION

[0009] Figure 1 illustrates a schematic diagram of an integrated circuit (IC) 100 for a push-pull driver. The IC 100 has a push controller 10 and a pull controller 20 contained within a general controller 18. The push controller 10 is connected to a switch 12, and the pull controller 20 is connected to a switch 22. The first switch 12interrupts a power line 38 connecting a positive voltage input 34 to the output 30, and the second switch 22 connects the output 30 to a ground 36. During operation of the circuit in push-pull mode only one of the switches is in a closed state at any given time. Proper synchronous control of the switches 12, 22 is guaranteed through the use of the general controller 18 which can control the timing of each of the push controller 10 and the pull controller 20. Additionally connected to the power line 38 is a driver output 30. The driver output 30 is connected between the switches 12, 22. A single controller input line 32 sends an input to both the push controller 10 and the pull controller 20 and is capable of setting the operational mode of the push-pull driver. Alternately, two individual controller input lines could be used to the same effect. The IC 100 also has diagnostic circuitry 14, 24 connected to each of the controllers 10, 20 which can analyze the outputs of the controllers 10, 20 as well as determine the health and functionality of the overall IC 100 in its current operational mode.

[0010] When operating in the default push-pull mode, the push controller 10 and the pull controller 20 alternate which switch 12, 22 is turned on. By way of example, if a +5V output is required for the high voltage forcing, and a OV output is required for the low voltage forcing, the voltage source 34 has an input voltage of approximately 5V. Typically, this input is achieved through the use of a DC voltage source, such as a battery. When the output 30 is desired to be at +5V, the push controller 10 closes the switch 12, and the pull controller 20 opens the switch 22, resulting in creation of a current flowpath from the voltage source 34 input to the push-pull output 30. Likewise, when a forced OV output is desired, the pull controller 20 closes the switch 22, and the push controller 10 opens the switch 12 resulting in a direct flow path from the push-pull output 30 to ground 36, thereby achieving a OV output. When it is not desirable to force the output 30 to either mode, both the switches 12, 22 are open and no current flow path is provided to the output 30

[0011] Each of the controllers 10, 20 of Figure 1 are additionally configured to operate the IC 100 in a "low-side pull" mode when they receive a preconfigurable input on the controller input line 32. A schematic diagram of the IC 100 of Figure 1 operating in low-side pull mode is illustrated in Figure 2 (IC 200) with non-relevant electrical components removed. In low-side pull mode the majority of the high side electronics illustrated in Figure 1 are disconnected resulting in the electrical schematic of IC 200 in Figure 2. While IC 200 maintains identical physical components to IC 100, due to the affect of the disconnected electronics in low-side pull mode, the circuit components have been renumbered for Figure 2.

[0012] In Figure 2, the control input 132 is connected to each of the high side controller 110 and the low side controller 120, and places the IC 200 into the low-side pull mode when a pre-configured input is received. In order to operate in low-side pull mode, the push controller 110 switches the high side switch 12 (illustrated in Figure 1) open and the high side switch 12 remains in the open state for the duration of the low- side pull mode operations. Consequently, the switch 12 has a negligible electrical effect, and is not illustrated in Figure 2. The pull controller 120 is connected to a second switch 122, and diagnostic circuitry 124 is connected in the same manner as when the IC 200 is operating in push-pull mode (illustrated in Figure 1).

[0013] While operating in a low-side pull mode, the pull controller 120 closes the switch 122 when in the default state, thereby creating a constant, direct flow path between the output 130 and the ground 136. When a low voltage (OV) output is required, the pull controller 120 closes the switch 122, thereby pulling the output 130 to ground. This allows for the output 130 to be passively high, while at the same time able to be forced to OV (ground).

[0014] The modifiable configuration of the IC 100, 200 of Figures 1 and 2 allows a single IC to be manufactured, and utilized in multiple different applications. The push controller 10 and the pull controller 20 can also have a memory unit which is capable of retaining the operational mode of the push-pull controller even after a control input 32, 132 has been disconnected. This allows the IC to be configured and then the control signal removed, thereby allowing for use in a broader range of applications. The push-pull / low-side pull mode can be changed or reset by either sending a reset signal to the control input 132, 32 or by removing power from the IC 100, 200. In the case that power is removed form the IC 100, 200, a "default" mode will be entered up on repowering the IC 100, 200. The default mode can be determined during manufacturing, and programmed into the controllers 10, 20.

[0015] Accordingly, the IC 100/200 of Figures 1 and 2 can accept a control input32/132, and based on that control input 32/132 determine what mode to operate in. Once the operational mode has been determined, the push controller 10/110 and the pull controller 20/120 engage in the actions described above to force the output 30/130 to the appropriate values. The controllers 10/110, 20/120 can then control the timing of the voltage on the output 30/130 by opening and closing the appropriate switches 12, 22/122 whenever the output needs to be changed. If an internal memory is used in the controllers 10/110, 20/120 a continued input 32/132 is not necessary, and instead the controllers 10/110, 20/120 will stay in their current operational mode until a new input 32/132 replaces the stored input value. [0016] A typical use of the modifiable IC 100/200 is illustrated in Figure 3. In Figure 3, the IC 100/200 output 130/30 is connected to a power train controller 210. The output 130/30 can then output a control signal which has either a high value or a low value, when the IC 100/200 is in a low-side pull mode, or a high value, a low value, or no value, when the IC 100/200 is in a push-pull mode. By way of example, the IC 100/200 could be used in a diesel power train control apparatus 300 to control a relay by being operated in a low-side pull mode. The same IC 100/200 could also be used in a gasoline engine power- train controller apparatus 300 to control spark timing by being operated in a push-pull mode. The IC 100/200 mode is controlled as described above with regards to Figures 1 and 2 by a control input 232.

[0017] In the example illustrated in Figures 1 and 2, the switches are shown as being FET' s (field effect transistors). However, alternate configurations could use other types of electrical switches to perform the same function. Alternately, a network of multiple electrical switches could provide the same function. These and other alternatives fall within the above disclosure, and a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention.

Claims

CLAIMSWhat is claimed is:

1. A push-pull driver integrated circuit comprising; a push controller having a mode control input port; a pull controller having a mode control input port; a controller input connected to each of said push controller mode control input port and said pull controller mode control input port; a first switch controllably coupled to said push controller and connecting a power input to a push-pull output; a second switch controllably coupled to said pull controller and connecting an electrical ground source to a push-pull output; and each of said pull controller and said push controller having a push-pull driver mode and a low-side pull driver mode.

2. The push-pull driver integrated circuit of claim 1, wherein each of said push controller and said pull controller are capable of operating the push-pull driver in a push-pull mode when said controller input is a first value.

3. The push-pull driver integrated circuit of claim 2, wherein each of said pull controller and said push controller are capable of operating said push-pull driver in a low-side pull mode when said controller input is a second value.

4. The push-pull driver integrated circuit of claim 3, wherein said first switch operates as a pass-through component when said push controller and said pull controller are operating in a low-side pull mode.

5. The push-pull driver integrated circuit of claim 3, wherein each of said pull controller and said push controller comprise a memory unit capable of storing a controller input value.

6. The push-pull driver integrated circuit of claim 1, further comprising diagnostic circuitry capable of detecting at least a status of the push-pull output connected to said push controller, and, diagnostic circuitry capable of detecting at least a status of the push-pull output circuitry connected to said pull controller.

7. The push-pull driver integrated circuit of claim 1, wherein said push controller and said pull controller each comprise a memory capable of storing a controller input value, and wherein said memory in said push controller and said memory in said pull controller is reset to a controller input value when a new controller input value is received.

8. The push-pull driver integrated circuit of claim 1, wherein each of said first switch and said second switch comprise at least one field effect transistor.

9. A method of configuring a configurable push-pull driver comprising the steps of: accepting a control input at each of a push controller and a pull controller; determining a value of said control input; operating said pull controller and said push controller in a push-pull mode when said input is a first value; and operating said pull controller and said push controller in a low-side pull mode when said input is a second value.

10. The method of claim 9, wherein said step of operating said pull controller and said push controller in a push-pull mode comprises; said push controller switching a first switch closed when an output is desired to be forced to a high voltage, thereby directly connecting said output to a voltage source, and said push controller switching said first switch open when an output is not desired to force to a high voltage; and said pull controller switching a second switch open when said output is desired to be forced to a zero voltage, thereby directly connecting said output to a ground, and said pull controller switching said second switch open when an output is not desired to be forced to a zero voltage.

11. The method of claim 9, wherein said step of operating said pull controller and said push controller in a low- side pull mode comprises; said push controller switching a first switch closed, thereby directly connecting said output to a voltage source; said pull controller switching a second switch closed when said output is desired to be forced to a zero voltage, thereby directly connecting said voltage source and said output to ground; and said pull controller switching said second switch open when said output is desired to be maintained at a high voltage.

12. The method of claim 9, further comprising the steps of; storing said control input value in a memory; and overwriting a currently stored control input value when a new control input value is received.

13. The method of claim 12, wherein said steps of operating said pull controller and said push controller in a push-pull mode when said input is a first value, and operating said pull controller and said push controller in a low-side pull mode when said input is a second value utilize a stored control input value when no control input value is detected.

14. A power train control assembly comprising; a configurable push-pull driver integrated circuit, comprising a push controller, a pull controller, a first switch controllably coupled to said push controller and connecting a power input to a push-pull output, a second switch controllably coupled to said pull controller and connecting an electrical ground source to a push-pull output, and each of said pull controller and said push controller having a push-pull driver mode and a low-side pull driver mode; and a timer receiving an output from the configurable push-pull driver integrated circuit that controls output of a timing signal from the power train controller.

15. The power train control assembly of claim 14, wherein each of said push controller and said pull controller includes a mode control input port and a controller input connected to each of said mode control input port.

16. The power train control assembly of claim 15, wherein each of said push controller and said pull controller are capable of operating the push-pull driver in a push-pull mode when a controller input is a first value, and wherein each of said pull controller and said push controller are capable of operating said push-pull driver in a low-side pull mode when said controller input is a second value.

17. The power train control assembly of claim 16, wherein said first switch operates as a pass-through component when said push controller and said pull controller are operating in a low-side pull mode.

18. The power train control assembly of claim 16, wherein each of said pull controller and said push controller comprise a memory unit capable of storing a controller input value.

19. The power train control assembly of claim 14, wherein said push controller and said pull controller each comprise a memory capable of storing a controller input value, and wherein said memory in said push controller and said memory in said pull controller is reset to a controller input value when a new controller input value is received.

20. The power train control assembly of claim 14, wherein each of said first switch and said second switch comprise at least one field effect transistor.