JPH02250369A - Semiconductor device - Google Patents

Abstract

PURPOSE:To maintain a device close to thermal equilibrium by a method wherein one or more of a plurality of semiconductor elements are divided into a plurality of pieces to have the other element interposed or so that they are mutually interposed. CONSTITUTION:One or more of a plurality of semiconductor elements 2 are divided into a plurality of pieces to have the other element interposed or so that they are mutually interposed. For example, as shown in the figure, a transistor q2 which is especially large in emitter size is divided into two transistors q2A, q2B to be arranged so that the other transistor q1 is interposed between them. Thus even if the temperature of q2A is lower than that of q1 as reference, the temperature of entire q2 is averaged, so that q1 and q2 can have characteristics equal or approximate to those in thermal equilibrium.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a semiconductor device, and particularly to a semiconductor integrated circuit in which a plurality of semiconductor elements formed on one semiconductor substrate need to be arranged in a thermally balanced state. Regarding equipment.

[Prior art]

When a single element that generates a large amount of heat and multiple other elements whose characteristics are easily affected by heat coexist on one semiconductor substrate (chip), a means to reduce the temperature difference between the elements in the same chip. "Integrated Circuit Engineering +21j p.
6 to 9, when the temperature coefficient is particularly a problem, examples of layouts are given, such as moving parts that generate a large amount of heat away from each other, or arranging specific parts along isothermal lines.

As shown in the schematic circuit diagram of FIG. 3, the three-terminal regulator has a power transistor Q on one side of one semiconductor substrate 1.
The output voltage can be obtained by placing B, G, and R (band gap reference) circuits on the other side, determining the reference voltage using the latter, and taking the resistance ratio with that reference voltage. In the present applicant, among the B, G, and R circuits, two transistors Ql that do not particularly require matching are used.

q2 were arranged adjacent to each other as shown in FIG.

[Problem to be solved by the invention]

In the three-terminal regulator described above, the oscillation margin etc. have been improved, but on the other hand, the basic characteristics of line regulation (stability of output voltage with respect to load current) and load regulation (stability of output voltage with respect to input voltage) This resulted in problems such as voltage stability) being worse than conventional products.

This is because the heat generated by the power transistor Q creates a temperature difference between the two transistors q1 and q2 that are most susceptible to heat in the B, G, and R circuits that determine the reference voltage, causing a deviation in VaE. This is because the reference voltage changes more.

The present invention has been made in view of the above-mentioned problems, and even when thermal unbalance occurs within the same chip, it is possible to maintain a plurality of elements that need to maintain thermal consistency in a state equivalent to or close to a thermally balanced state. The purpose is to provide a structure that can maintain close conditions.

[Means to solve the problem]

In order to achieve the above object, the semiconductor device of the present invention includes a plurality of semiconductor elements that need to maintain a thermal atmosphere on the surface of a single semiconductor substrate throughout its lifetime, and one of the semiconductor elements, (Some elements are divided into a plurality of parts, and these elements are arranged so as to sandwich other elements or to sandwich each other.

[Effect]

By further dividing a plurality of elements that need to maintain thermal balance and arranging them alternately, thermal balance is further maintained in terms of distance from the heat source, and fluctuations in load fluctuation voltage are reduced.

〔Example〕

FIG. 1 shows an embodiment of the present invention, in which the band gear rough is the most affected by the temperature rise during operation of the power transistor Q in an IA class three-terminal relay element (see FIG. 3). fist reference circuit 2
FIG. 2 is a partially enlarged plan view of the semiconductor device showing the arrangement of two transistors qleq2.

In the circuit shown in Figure 3, in the conventional circuit layout, ql
, q2 is most likely to fluctuate when the thermal balance of the transistors q2 and q2 is disturbed.
, q2BK and arranged so as to sandwich it from both sides of the other transistor q1.

Although not shown, q2A and q2B are electrically coupled to each other via KAA wiring.

As shown in FIG. 2, in the conventional structure when subjected to thermal influence, the thermal gradient curve between the two cords Q 1 * Q 2 has a steep angle, but in the present invention, the thermal gradient curve has a steep angle. Even if the temperature of Q2A of q2 becomes low based on ql, it is averaged over q2 as a whole and Ql and q2 are in thermal equilibrium. It will show characteristics equivalent to or similar to.

Since the thermal balance between ql and q2 is maintained in this way, the fluctuation in the reference voltage becomes smaller when the load on the power transistor Q changes.

However, depending on the form of the circuit, the same effect can be obtained by dividing both elements into a plurality of pieces and arranging them alternately.

〔Effect of the invention〕

By being able to maintain the thermal balance of specific elements of the band gap reference circuit, the fluctuation value was reduced to 50% or less, and the stability of the output voltage with respect to the power supply voltage and the stability of the output voltage with respect to the load current were significantly improved.

[Brief explanation of drawings]

FIG. 1 is a partially enlarged plan view (layout diagram) of a semiconductor device showing an embodiment of the present invention. FIG. 2 is a curve diagram showing the effect of heat balance due to element arrangement. FIG. 3 is a circuit diagram of a main part of a three-terminal regulator, and FIG. 4 is a partially enlarged plan view of a conventional semiconductor device. l...Semiconductor chip, 2...Semiconductor element area, Q.
...power transistor, ql, q2...transistor. Figure Figure Figure Figure

Claims (1)

[Claims] 1. A plurality of semiconductor elements that need to maintain thermal balance are formed on one main surface of one semiconductor substrate, and one or some of these elements are divided into multiple pieces. A semiconductor device characterized in that these elements are arranged so as to sandwich the other element or sandwich each other. 2. A two- and three-terminal regulator in which a pair of semiconductor elements is arranged, with one element sandwiching the other.