Motor Driver Semiconductor Circuit Without a Separate Enable Pin

Solution Overview

Problem

The existing semiconductor devices for motor systems require an additional enable terminal, increasing the number of external pins and leading to a larger device size, which is inefficient.

Innovation Solution

The semiconductor device configuration eliminates the need for an enable terminal by using a reference power supply circuit and a switch circuit that activates based on control input signals, reducing the number of pins required while maintaining functionality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If an enable terminal is added to control the semiconductor device, then the device functionality is improved, but the number of external pins increases and device size becomes larger

Engineering Contradiction:

Improvedevice functionalityVSAvoiddevice size

Core Design Contradiction:

Adaptability or versatilityVSArea of stationary object

Solution Approach 1:

The enable function is merged with the existing control input terminals. The reference power supply circuit monitors the logic levels at the upper and lower control input terminals to determine device activation, eliminating the need for a separate enable terminal. This combines the enable function with the control signal inputs already present in the system.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The control input terminals serve dual purposes: they control the half-bridge transistors and simultaneously activate the reference power supply circuit when both upper and lower control signals are at high logic levels. This multi-functionality removes the dedicated enable terminal while preserving the activation control capability.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If an enable terminal is added to control the semiconductor device, then the device functionality is improved, but the number of external pins increases

Engineering Contradiction:

Improvedevice functionalityVSAvoidnumber of external pins

Core Design Contradiction:

Adaptability or versatilityVSQuantity of substance

Solution Approach 1:

The enable function is merged with the existing control input terminals. The reference power supply circuit monitors the logic levels at the upper and lower control input terminals to determine device activation, eliminating the need for a separate enable terminal. This combines the enable function with the control signal inputs already present in the system.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The control input terminals serve dual purposes: they control the half-bridge transistors and simultaneously activate the reference power supply circuit when both upper and lower control signals are at high logic levels. This multi-functionality removes the dedicated enable terminal while preserving the activation control capability.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS20250015735A1Semiconductor device, motor system, and vehicle

Publication Date: 2025.01.09 ROHM CO LTD

AI summary

A semiconductor device comprises: an upper control input terminal; a lower control input terminal; a power supply terminal; a control logic unit; a reference power supply circuit configured to receive supply of the power supply voltage and to allow generation of a reference power supply voltage to be supplied to the control logic unit; and a switch circuit including switches provided for the upper control input signal and the lower control input signal respectively and switched between on and off in response to logic levels of the upper control input signal and the lower control input signal respectively. The reference power supply circuit is configured to be activated on the basis of a combination of the logic levels of the upper control input signal and the lower control input signal.