JP2003114242A - Integrated circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an integrated circuit capable of selecting a different delay time without changing the inside. SOLUTION: A potential dividing circuit comprising resistances 102, 103 connected in series is constituted between external terminals VDD, VSS, and connected to the minus input terminal of a voltage comparator 104. The plus input terminal of the voltage comparator 104 is connected to a reference voltage circuit 101, and the output terminal is connected to a delay circuit 105. The delay circuit 105 has terminals CTL1, CTL2 for setting the delay time and can select the terminal as the need arises.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to integrated circuits.

[0002]

2. Description of the Related Art A conventional integrated circuit is a circuit as shown in FIG. This is a voltage dividing circuit composed of a resistor 202 and a resistor 203 connected in series between a terminal VDD provided to apply a power supply voltage and VSS, and a reference voltage capable of generating a constant voltage. A generation circuit 201,
It is composed of a voltage comparison circuit 204 and a delay circuit 205.
The voltage comparison circuit 204 includes a plurality of transistors,
The divided voltage divided by the voltage dividing circuit is compared with the reference voltage generated by the reference voltage generating circuit 201. If the divided voltage is higher than the reference voltage, Hi is, and conversely, if it is low. Lo is output. The delay circuit 205 is
The output of the voltage comparison circuit 204 changes from Hi to Lo, or L
When a transition is made from o to Hi, a certain delay time is provided and the terminal VOUT is transitioned from Hi to Lo or from Lo to Hi.

[0003]

In the conventional integrated circuit,
When the delay circuit is built in the integrated circuit, the delay time cannot be selected from the outside, so that it is necessary to change the inside of the integrated circuit in order to set different delay times as needed.

Further, at the time of shipping inspection, there is a problem that the inspection time also becomes long especially when the delay time is long.

[0005]

In order to solve the above problems, an external terminal is provided so that the delay time can be selected.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit diagram of a voltage detection circuit according to the present invention. There is a resistor 102 and a resistor 103 connected in series between the external terminals VDD and VSS, and the resistor 102 and the resistor 103 are composed of a voltage dividing circuit capable of dividing the input power supply voltage at a predetermined ratio. The junction between the resistors 102 and 103 is connected to the negative input terminal of the voltage comparison circuit 104. On the other hand, the reference voltage circuit 101 capable of generating a constant reference voltage regardless of the magnitude of the power supply voltage is connected to the + input terminal of the voltage comparison circuit 104. Further, a delay circuit 105 is added to provide external terminals CTL1 and CTL2 so that the delay time can be selected.

In operation, the external terminal VSS is set to GND,
The voltage input from the external terminal VDD is divided by the voltage dividing circuit including the resistors 102 and 103. The divided voltage is compared with the reference voltage generated by the reference voltage generation circuit 101 in the voltage comparison circuit 104. Here, when the divided voltage becomes higher than the reference voltage circuit 101, the voltage comparison circuit 104 makes a transition from Lo to Hi, but VOUT becomes L after the delay time set by the delay circuit 105.
Transition from o to Hi.

The delay time is set to 4 seconds when both CTL1 and CTL2 are in the OPEN state, CTL1 is at the Lo level and CT is set.
1 second when L2 is OPEN, CTL1 is OPEN, C
When TL2 is Lo level, 0.25 seconds, CTL1, CT
For both L2 and Lo level, there is no delay time, and it can be selected as needed. Especially in shipping inspection, the inspection time is shortened by eliminating the delay time.

As described above, when the delay circuit is built in the integrated circuit, the delay time cannot be selected from the outside. Therefore, to set different delay times as needed,
It solves the problem of having to change the inside of the integrated circuit. Although the embodiments so far have been described with two external terminals, the number of external terminals is not limited.

If the present embodiment is an integrated circuit, it is a C-MOS.
(Complementary Metal Oxid
However, the invention is not limited to an eSemiconductor) circuit, a bipolar transistor circuit, and the like, and the realization is easy.

[0011]

The integrated circuit of the present invention has a structure in which an external terminal is provided and a delay time can be selected, and it is not necessary to change the inside of the integrated circuit in order to set different delay times as needed. There is an effect.

Further, at the time of shipping inspection, there is an effect that the inspection time can be shortened especially when the delay time is long.

[Brief description of drawings]

FIG. 1 is an integrated circuit diagram of the present invention.

FIG. 2 is a diagram showing a conventional integrated circuit.

[Explanation of symbols]

101 Reference voltage circuit 102 resistance 103 resistance 104 Voltage comparison circuit 105 delay circuit 201 Reference voltage circuit 202 resistance 203 resistance 204 delay circuit

Claims (3)

[Claims] 1. A voltage dividing circuit capable of dividing a voltage at a predetermined ratio, a reference voltage generating circuit capable of generating a constant reference voltage regardless of the magnitude of the voltage, and the input reference voltage. And the voltage divided by the voltage dividing circuit, the output voltage can be compared by switching the output signal, and the voltage detection circuit has a delay time. An integrated circuit characterized in that a delay time can be selected according to the state of a separately prepared terminal in a voltage detection circuit with a delay that can be detected. 2. A voltage dividing circuit capable of dividing a voltage at a predetermined ratio, a reference voltage generating circuit capable of generating a constant reference voltage regardless of the magnitude of the voltage, and the input reference voltage. And the voltage divided by the voltage dividing circuit, the output voltage can be compared by switching the output signal, and the voltage detection circuit has a delay time. A secondary battery protection integrated circuit including a circuit capable of detecting a delay time in a voltage detection circuit with a delay that can be detected according to a state of a separately prepared terminal. 3. A voltage dividing circuit capable of dividing a voltage at a predetermined ratio, a reference voltage generating circuit capable of generating a constant reference voltage regardless of the magnitude of the voltage, and the input reference voltage. And the voltage divided by the voltage dividing circuit, the output voltage can be compared by switching the output signal, and the voltage detection circuit has a delay time. An integrated circuit including a voltage detection circuit with delay capable of detecting, wherein the delay time can be selected according to the state of a separately prepared terminal.