JPH033192A - Write circuit for semiconductor device - Google Patents

Abstract

PURPOSE:To write real data at any time when they are inputted by generating a pulse by means of the changes of an address and the data and executing the write by means of the pulse. CONSTITUTION:When the address, a write control signal and the data are given, the address is inverted, thereby, a pulse A is generated by a circuit 10a to generate the pulse with the address change, and the pulse A is made into a pulse B with a wide pulse width by a circuit 10b to enlarge the pulse width. Since the write control signal to a write control pin 1 is fixed at an 'L', the level of a node H is fixed at an 'H', and the waveform of the pulse B is invert ed. In the same way, at the time of inverting the data, a pulse F is obtained by a circuit 10d to generate the pulse with the data change and a circuit 10c to enlarge the pulse width, the OR of the waveform of the pulse C and the waveform of the pulse F is obtained, a new write control signal G is generated, and the normal write action can be executed at any time when the data are inputted.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a write circuit for a semiconductor device, and in particular, the present invention relates to a write circuit for a semiconductor device, and in particular, the present invention relates to a write circuit for a semiconductor device. The present invention relates to a write circuit that can write data.

[Conventional technology]

FIG. 3 shows an example of a write circuit of a conventional semiconductor device. In the figure, 1 and 2 are TTL level input signals, and 3 to 2 are TTL level input signals.
6 is an Nch transistor for driving the IO line or 10 lines, E is the ■0 line, and F is the ■σ line. Also, Figure 4 is TL
FIG. 6 is a diagram showing the timing at which writing is possible when the L level input signal 1 is fixed at "L11".

Next, the operation will be explained. In the figure, when a TTL level is input from terminals 1 and 2, the rise and fall times are controlled by changing the size of the NOR circuit and N07 circuit (these Pch) transistors and Nch) transistors connected to them. ) by M
It is converted to O3 level (internal power supply level).

Now, when “H” level is input to terminal 1, level A becomes H.
”, and regardless of the level of B, levels C and D become “L”, and Nch) transistors 3 to 6 are all turned on.
No L. Therefore, the 0th order terminal 1 that can be read is “°
When the level becomes L°°, level A becomes L11, and level C and D become “H” and “L” due to the input to terminal 2.
” and °′L” become “H”, Nch transistors 4 and 5. Or 3 and 6 are ONL, level E, F
By becoming "H", "L11" or "L", HII, "H" or "L" can be written into the memory cell.

Also, if the level of terminal 1 is fixed at L'', the level of the fourth
As shown in the figure, the true data must be entered at the end of Add. This means that this write control signal “
The state where L is fixed at 11 means that data is always being written. For example, if true data is written before Add, the write control signal will still be "L" even after writing. This is because it is not known what kind of data will be written next.

[Problem to be solved by the invention]

The write circuit of a conventional semiconductor device is configured as described above, so if the write control signal is fixed to "L", true data must be input at the end of the cycle, and the true data must be input at the end of the cycle. No matter when I entered the data, I could not write it.

This invention has been made to solve the above-mentioned problems, and it is possible to write data to a semiconductor device that can write true data whenever it is input when the write control signal is fixed at "L". The purpose is to obtain a circuit.

[Means to solve the problem]

The write circuit for a semiconductor device according to the present invention generates a pulse when the address and data change when the write control signal is fixed to "L", and writes data by using the pulse. This allows normal writing to occur no matter when is input.

[Effect]

The write circuit for a semiconductor device according to the present invention performs a write operation based on a change in address or data even when a write control signal is fixed at "L", thereby ensuring a normal write operation no matter when input data is input. It will be done.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 to 6 are the same as the conventional circuit described above.

10 is a write control signal generation circuit that generates a pulse when an address or data changes, and creates a new write control signal by combining the pulse and a write control signal; 10a is a circuit that generates a pulse when an address changes; 10b , 10c is a circuit that increases the pulse width, and 10d is a circuit that generates a pulse based on data changes.

Next, the operation will be explained. FIG. 2 is a timing chart of the above embodiment.

Assume that an address, write control signal, and data as shown in FIG. 2 are given. First, a pulse A is generated by the circuit 10a by inverting the address, and its pulse width is widened by the circuit 10b, resulting in a waveform B. Since the write control signal to bin 1 is fixed at “L”,
The level of node H is fixed at "H", and the inverted waveform of the B waveform becomes the C waveform. Similarly, when the data is inverted, the E and F waveforms are obtained by the circuits 10d and 10c. The logical sum of the C waveform and the F waveform becomes the G waveform, and this waveform functions in the same way as the write control signal of the conventional circuit.

Therefore, in this embodiment, when the address is inverted, the data at that time is written once, and even if the data is subsequently inverted, the inverted data is written again. In addition, in this embodiment, the write control signal is
By keeping it at L°, there is also the effect that the write cycle can be shortened.

[Effects of the Invention] As described above, according to the present invention, a pulse is generated when the address or data changes, and writing is performed using the pulse, so that the write control signal of the semiconductor device becomes "L11". In a fixed state, a normal write operation can be performed no matter when data is input.Also, by keeping the write control signal at "L"°, it is possible to obtain the effect of shortening the write cycle. can.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a write circuit of a semiconductor device according to an embodiment of the present invention, FIG. 2 is a timing chart of each part of the above embodiment, and FIG. 3 is a circuit diagram of a write circuit of a conventional semiconductor device. FIG. 4 is a timing chart for performing a normal write operation when the write control signal is fixed at "L" in a conventional write circuit. 1...Write control pin, 2...Data bin, 3~
6...N-channel transistor, 10... A circuit that generates a write control signal based on address and data. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] (1) In a write circuit of a semiconductor device, a means for generating a pulse in response to a change in address, a means for generating a pulse in response to a change in input data, and a means for generating a pulse in response to a change in input data, even when the write control signal is fixed at "L". A write circuit for a semiconductor device, comprising data write means for writing data each time there is an output from the pulse generation means.