NTE21128 NTE ELECTRONICS, NTE21128 Datasheet - Page 5

• Manufacturer Part Number: NTE21128
• Description: IC, EPROM, 128KBIT, 250NS, DIP-28
• Manufacturer: NTE ELECTRONICS

Specifications of NTE21128

• Memory Type: EPROM - OTP
• Memory Size: 128Kbit
• Memory Configuration: 16K X 8
• Access Time: 250ns
• Supply Voltage Range: 4.75V To 5.25V
• Memory Case Style: DIP
• No. Of Pins: 28

Device Operation (Cont’d):
Program Inhibit
Programming of multiple NTE21128s in parallel with different data is also easily accomplished. Ex-
cept for E, all like inputs (including G) of the parallel NTE21128 may be common. A TTL low pulse
applied to an NTE21128’s E input, with V
inhibits the other NTE21128s from being programmed.
Program Verify
A verify should be performed on the programmed bits to determine that they were correctly pro-
grammed. The verify is accomplished with G = V
Erasure Operation:
The erasure characteristic of the NTE21128 is such that erasure begins when the cells are exposed
to light with wavelengths shorter than approximately 4000 angstroms. The recommended erasure
procedure for the NTE21128 is exposure to short wave ultraviolet light which has a wavelength of
2537 angstroms. The integrated dose (i.e. UV intensity x exposure time) for erasure should be a mini-
mum of 15 W sec/cm
an ultraviolet lamp with 12000 W/cm
(1 inch) of the lamp tubes during the erasure. Some lamps have a filter on their tubes which should
be removed before erasure.
2
. The erasure time with this dosage is approximately 15 to 20 minutes using
GND
A12
V
2
O0
O1
O2
A7
A6
A5
A4
A3
A2
A1
A0
Pin Connection Diagram
PP
power rating. The NTE21128 should be placed within 2.5cm
PP
10
11
12
13
14
= 12.5V, will program that NTE21128> A high level E input
1
2
3
4
5
6
7
8
9
IL
, E = V
28
27
26
25
24
23
22
21
20
19
18
17
16
15
PGM
OE
CE
IL
A13
A8
A9
A11
A10
O7
O6
O5
O4
O3
V
, P = V
CC
IH
, and V
PP
at 12.5V.