JPS607696A - Eprom erasing device - Google Patents

Abstract

PURPOSE:To execute erasing work efficiently by controlling the quantity of irradiation of ultraviolet rays for erasing and applying a blank checking function to the titled device. CONSTITUTION:Ultraviolet rays from an ultraviolet ray lamp group 1 are irradiated to an EPROM4 to be erased which is set up on a setting jig 2. The intensity of the ultraviolet rays is measured by an ultraviolet intensity meter 5 through an ultraviolet ray sensor 3 and the measured value is A/D converted 6 and supplied to an ultraviolet irradiation control circuit 7. Receiving the A/D converted signal, the control circuit 7 regulates the irradiation time of ultraviolet rays and sets up an electronic timer 13. After the set irradiation time has been passed, the supply of ultraviolet rays is interrupted and a blank checking electric circuit 8 is actuated to execute blank check. If erasing is incomplete, an erase command is outputted to the control circuit 7 again and the erasing work is repeated again. Thus, the erasing work can be executed efficiently.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to an EPROM erasing device, and more particularly to an EPROM erasing device having a function of performing a blank check after erasing written information.

(b) Prior art and problems A MOS type non-volatile semiconductor element is irradiated with ultraviolet rays to erase information that has been written in the element for the first time,
Erasable programmable ROMs (hereinafter referred to as EPROMs) that can be rewritten are well known. Kagaru IE l) ROM is used as a memory element in electronic equipment.

When it becomes necessary to erase and initialize information that has conventionally been written in such an EPROM due to a design change, for example, the EPROM erasing device is equipped with a large number of EPROMs to be erased in an EPROM installation jig. A large number of ultraviolet lamps are installed at a predetermined distance from the installation jig, and the information stored in the EFROM is removed by irradiating ultraviolet light for a predetermined period of time using a timer, etc. I was trying to delete it. In this case, the EPR to be erased
Since the erase energy value of the OM is known in advance, the erase energy is controlled by controlling the irradiation time of the ultraviolet lamp using a timer or the like depending on the ultraviolet intensity of the ultraviolet lamp used.

However, in such conventional devices, the UV intensity of the UV lamp varies depending on the lamp, and the amount of UV irradiation from the UV lamp changes between when the lamp starts to be used and when a predetermined period of time has elapsed. Since it does not have a function to calculate the time used,
It is difficult to control the erase energy of EPROM,
When setting the UV irradiation time using a timer, workers were relying on their intuition.

Furthermore, in the conventional EPROM erasing device, the E
FROM does not have a blank check function to determine whether information has been erased or not, so after removing the erased EPROM from the EPROM eraser and performing a blank check, it was found that the erase was insufficient. When erasing a large number of EFROMs, it is necessary to install the EPROM again in the EPROM erasing device and perform the erasing operation, which has the disadvantage that the erasing operation is complicated, especially when erasing a large number of EFROMs.

Furthermore, since the irradiation intensity of ultraviolet rays is not accurately measured and the amount of irradiation of the ultraviolet rays is not controlled, there has been a problem that the EFROM to be erased may be destroyed.

(C1 Purpose of the Invention The present invention eliminates the above-mentioned drawbacks, makes it possible to precisely control the irradiation energy of the ultraviolet rays, and provides a blank check function, so that the erasing work can be performed efficiently without causing damage to the element. A new EPROM that enables
The purpose is to provide an erasing device.

(d+ Structure of the Invention To achieve the above object, the EPROM erasing device of the present invention has an EPROM in which an ultraviolet lamp and an ultraviolet light receiving sensor are incorporated, and information to be erased is written therein.
an ultraviolet irradiation amount control circuit into which an erasing energy that meets the specifications of the E-PROM to be erased is input, an electronic timer that regulates the ultraviolet irradiation time, and a After placing the EFROM in which the information to be erased is written, which consists of a blank check electric circuit that performs a blank check on the EPROM, on an installation jig, the installation jig is placed under an ultraviolet lamp, and the ultraviolet lamp is irradiating the EFROM with the irradiation light, detecting the intensity of the ultraviolet rays with an ultraviolet light receiving sensor, and based on the detected information, specifying the irradiation time with an ultraviolet irradiation amount control circuit into which erase energy information is input in advance, EPR to be erased by automatically setting the electronic timer at the specified time
After erasing the information written in the EPR'OM by irradiating the OM with ultraviolet rays having a predetermined ultraviolet intensity for a specified time, the erased EPR'OM is This is characterized in that the EFROM after a blank check is additionally erased while controlling the irradiation amount using a circuit.

tel Embodiment of the Invention An embodiment of the invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram of an EPROM erasing device of the present invention, and FIG. 2 is a plan view schematically showing the installation mode of an E I) ROM to be erased in the EPROM erasing device of the present invention.

In Figures 1 and 2, ■ indicates a group of ultraviolet lamps, 2
is an installation jig in which the ultraviolet sensor 3 is installed and a large number of EPROMs 4 are placed, 5 is the ultraviolet intensity needle, and 6 is A-D.
Converter, 7 is an ultraviolet irradiation amount control circuit, 8 is an electric circuit for blank checking, 9 is an operation panel having a lamp 10, an element changeover switch 11, and an address display I2 for the odor element, 13 is an electronic timer. , 14 is a DC power supply.

As shown in Figures 1 and 2, the EPROM to be erased is placed on the EPROM installation jig 2 vertically and horizontally in a predetermined position.
A UV lamp group 1 consisting of a predetermined number of UV lamps is installed on a predetermined number of EPROMs.

Next, the element switching switch 1 of the operation panel 9 is turned on according to the erase energy of the EPROM to be erased, and the power source 14 is turned on. Then, the ultraviolet lamp group 1 starts irradiating the ultraviolet rays, and the ultraviolet intensity of the ultraviolet lamp group 1 is detected by the ultraviolet sensor 3 installed on the installation jig 2. Calculate the strength of The output signal of this ultraviolet intensity meter is converted to A-1) converter 6.
After converting it into a digital output signal, the output signal is input to the ultraviolet irradiation amount control circuit 7.

This ultraviolet irradiation amount control circuit 7 contains an EPROM to be erased.
The erasing energy value No. 4 is input in advance, and the ultraviolet irradiation time is calculated from the input erasing energy value and the signal output from the ultraviolet intensity meter 5, and the calculated ultraviolet irradiation time is set on an electronic timer. 13 to automatically set the electronic timer 13. In this way, the ultraviolet lamp group is used to irradiate the EPROM to be erased with ultraviolet light according to the set irradiation time, and when the set irradiation time has elapsed, the power supply to the ultraviolet lamp group is cut off and the blank check is performed. The electric circuit 8 operates, and if erasing is incomplete, it outputs an erasing command again to the ultraviolet irradiation amount control circuit 7, and repeats the erasing operation again. After repeating the erasing operation in this way, the blank check electric circuit 8 is operated again to perform a blank check.
When the erasure is completed, the erasure completion indicator lamp 10 on the operation panel 9 lights up to indicate that the erasure is complete. If the erasing is insufficient, the defective element display 12 on the operation panel 9 is activated to display an address signal indicating the position on the installation jig where the defective E PROM that cannot be erased is installed, and to indicate the location of the defective element. Check the position on the installation jig.

According to such an EP ROM erasing device, the erasing energy used for erasing the EFROM is controlled with high precision, the erasing time is automatically set using the controlled erasing energy, and the blank check work after erasing can be done without any trouble. Since there is nothing to take, EPl'? The OM erasing work can be performed with high reliability, and the efficiency of the EPROM erasing work is also improved.

Further, as another embodiment of the present embodiment described above, a buzzer may be used to indicate the end of the erasing operation instead of the indicator lamp that indicates the end of the erasing operation.

if) Effects of the Invention As described above, according to the EPROM erasing device of the present invention, the ultraviolet ray irradiation port used for the EPROM erasing operation is controlled, and the EFROM blank check after the erasing operation is automatically performed. Erasing work is efficient and produces practical effects.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the electric circuit of the EPROM erasing device of the present invention, and FIG. 2 is a block diagram showing the manner in which the ROM is installed on the installation jig of the EPROM erasing device of the present invention. FIG. In the figure, ■ is a group of ultraviolet lamps, 2 is an EPROM installation jig, 3 is an ultraviolet sensor, 4 is an EPROM, 5 is an ultraviolet intensity meter, 6 is an A-D converter, 7 is an ultraviolet irradiation amount control circuit, 8 is a blank check electric circuit, 9 is an operation panel, 10 is an indicator lamp, 11 is an element changeover switch,
12 is a defective element address display, 13 is an electronic timer, and 14 is a DC power supply.

Claims (1)

[Claims] An ultraviolet lamp, an installation jig for mounting an EPROM with a built-in ultraviolet light receiving sensor and information to be erased, and an erasing energy appropriate for the specifications of the E'PROM to be erased. The jig is used to install the EFROM containing the information to be erased, which consists of an ultraviolet irradiation amount control circuit, an electronic timer that regulates the ultraviolet irradiation time, and a blank check electric circuit that performs a blank check of the EFROM after erasing. After placing the installation jig under an ultraviolet lamp, the EIROM is irradiated with the irradiation light of the ultraviolet lamp, and the intensity of the ultraviolet rays is detected by the ultraviolet light receiving sensor, and the detected information is Based on this, the irradiation time is specified by the ultraviolet ray irradiation amount control circuit into which erasing energy information is input in advance, and the electronic timer is automatically set at the specified time to erase the EPRO to be erased.
After erasing the information written in the EPROM by irradiating the M with ultraviolet light having a predetermined ultraviolet intensity for a specified time, and after performing a blank check on the erased EPROM, the irradiation amount is adjusted again using the ultraviolet irradiation amount control circuit. An F-FROM erasing device is characterized in that it additionally erases an EPROM after a blank check while controlling it.