TSC87C51 TEMIC Semiconductors, TSC87C51 Datasheet - Page 12

• Manufacturer Part Number: TSC87C51
• Description: CMOS 0 to 25 MHz Programmable 8-bit Microcontroller
• Manufacturer: TEMIC Semiconductors

12
TSC87C51
Signature bytes
The
for EPROM verify but activate the control lines provided in Table 5 for Read Signature Bytes. Table 6 shows the
content of the signature byte for the
Table 6 Signature bytes content
EPROM Erasure (Windowed Packages Only)
Erasing the EPROM erases the code array and also the encryption array returning the parts to full functionality.
Erasure leaves all the EPROM cells in a 1’s state.
Erasure Characteristics
The recommended erasure procedure is exposure to ultraviolet light (at 2537 Å) to an integrated dose at least 15
W–sec/cm
about 25 mm, should be sufficient.
Erasure of the EPROM begins to occur when the chip is exposed to light with wavelength shorter than approximately
4,000 Å. Since sunlight and fluorescent lighting have wavelengths in this range, exposure to these light sources over
an extended time (about 1 week in sunlight, or 3 years in room–level fluorescent lighting) could cause inadvertent
erasure. If an application subjects the device to this type of exposure, it is suggested that an opaque label be placed
over the window.
TSC87C51
2
ALE/PROG
. Exposing the EPROM to an ultraviolet lamp of 12,000 W/cm
Location
A0–A11
EA/VPP
Control
signals
D0–D7
30h
31h
60h
61h
has four signature bytes in location 30h, 31h, 60h and 61h. To read these bytes follow the procedure
12.75V
5V
0V
Figure 7 Programming and verification signal’s waveform
Programming Cycle
TSC87C51
1
Data In
100us
2 3
Contents
.
XXh
9Eh
4
58h
58h
10us
5
Customer selection byte: TEMIC
Family selection byte: C51
TSC87C51
Product revision number
Read/Verify Cycle
2
Data Out
rating for 30 minutes, at a distance of
Comment
Rev. E
–
July 03, 2000