SGS Thomson Microelectronics M2732A-20F6, M2732A-20F1, M2732A-F6, M2732A-F1, M2732A-4F1 Datasheet

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AI00780B

A0-A11 Q0-Q7

M2732A

Figure 1. Logic Diag ra m

M2732A

NMOS 32K (4K x 8) UV EPROM

FA ST ACCESS TIME: 200ns EXTENDED TEMPERATURE RANGE SINGLE 5V SUPPLY VOLTAGE LOW STANDBY CURRE NT: 35mA max INPUTS and OUTP UT S TT L CO MPATIB LE

DURING REA D a n d PRO GR AM COM P LETELY STATIC

DESCRIP TION

The M2732A is a 32,768 bit UV erasable and electrically programmable memory EPROM. It is organized as 4,0 96 words by 8 bit s. The M2732A with its single 5V pow er supply an d with an acc ess time of 200 ns, is ideal suited for applications wher e fast turn around and pattern experimentation one important requirements.

The M2732A is honsed in a 24 pin Window Ceramic Frit-Seal Dual-in-Line pac kage. The transparent lid allows the user to expose the chip t o ultraviolet light to erase the bit patt ern. A new pattern can be then written to the cleric e by following t he programmi ng procedure.

A0 - A11 Address Inputs Q0 - Q7 Data Outputs E Chip Enable GV

Output Enable / Program Supply

Supply Voltage

Ground

T able 1. Signal Names

FDIP24W (F)

July 1994 1/9

A0 Q0 Q1

A10 E

A11

Q7 Q6

AI00781

M2732A

1 2 3 4 5 6 7

9 10 11 12

20 19 18 17 16 15

23 22 21

14 13

Figure 2. DIP Pin Connecti ons

Symbol Parameter Value Unit

Ambient Operating Temperature grade 1

grade 6

0 to 70

–40 to 85

°C

BIAS

Temperature Under Bias grade 1

grade 6

–10 to 80 –50 to 95

°C

STG

Storage Temperature –65 to 125 °C

Input or Output Voltages –0.6 to 6 V

Supply Voltage –0.6 to 6 V

Program Supply Voltage –0.6 to 22 V

Note: Except for the rating "Operating T emperature R ange", stresses above those lis ted in the Table "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only and opera tion of the device at these or any other conditions above those indicated in the Operating sections of this specification is not implied. Exposure to Absolute Maximum Rati ng conditions for extended periods may affect device reliabil ity. Refer also to the SGS-THOMSON SURE Program and other relevant quality documents.

Tab le 2. Absol ute Maxim u m Ratin gs

DEVICE OPER ATION

The six modes of operation for the M2732A are listed in the Operating Modes Table. A single 5V power supply is required in the read mode. All inputs are TTL level except for V

PP.

Read Mode

The M2732A has two control functions, both of which must be logically satisfied in order to obtai n data at the outputs. Chip Enable (

E) is the power control and should be used for device selection. Output Enable (

G) is the output control and should

be used to gate data to the output pins, independent of device selection.

Assuming that the addresses are stable, address access time (t

AVAQ

) is equal to the delay fr om E to

output (t

ELQV

). Data is available at the outputs after

the falling edge of

G, assuming that E has been low and the addresses have been stable for at least t

AVQ V-tGLQV

Stand by Mod e

The M2732A has a standby mode which reduces the active power current by 70 %, from 125 mA to 35 mA. The M2732A is placed in the sta ndby mode by applying a TTL high signal to

E input. When in standby mode, the outputs are in a high impedance state, independent of the

GVPP input.

Two Line Output Control

Because M2732A ’s are usually used in larger memory arrays, this product features a 2 line control function which accommodates the use of multiple memory connection. The two line control function allows:

a. the lowest possible memory power dissipation, b. complete assurance that output bus content i on

will not occur.

To most efficiently use these two control lines, it is recommended that

E be decoded and used as the

primary device selecting function, while

G should be made a common connection to all devices in the array and connected to the

READ line from the

system control bus. This ensures that all deselected memory devices

are in their low power standby mode and that the output pins are only active when data is required from a particular memory device.

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M2732A

Programmin g

When delivered, and after each erasure, all bits of the M2732A are in the “1" state. Data is introduce d by selectively programming ”0’s" into the desired bit locations. Although only “0’s” will be programmed, both “1’s” a nd “0’s” c an be present ed in the data word. The only way to change a “0" to a ”1" is by ultraviolet light erasure.

The M2732A is in the programming mode when the GVPP input is at 21V. A 0.1µF capacitor must be placed across

GVPP and ground to suppress spurious voltage transients which may damage the device. The data to be programmed is applied, 8 bits in parallel, to the data output pins. The levels required for the address and data inputs are TTL.

When the address and data are stable, a 50ms, active low, TTL program pulse is applied to the

E input. A program pulse must be applied at each address location to be programmed. Any location can be programmed at any time - either individually , sequentially, or at random. T he program pulse has a maximum width of 55ms. The M2732A must not be programmed with a DC signal applied to the

E input.

Programming of multiple M2732As in parallel with the same data can be easily accomplished due to the simplicity of the programming requirements. Inputs of the paralleled M2732As may be connected together when they are programmed with the same data. A low level TTL pulse applied to the E input programs the paralleled 2732As.

Program Inhibit

Programming of multiple M2732As in parallel with different data is also easily accomplished. Except for

E, all like inputs (including GVPP) of the parallel

M2732As may be common. A T TL level program

pulse applied to a M2732A’s

E input with GV

21V will program that M2732A. A high level

E input inhibits the other M2732As from being programmed.

Program Verify

A verify should be performed on the programmed bits to determine that they were correctly programmed. The verify is carried out with

GVPP and

E at VIL. ERASURE OPERATION The erasure characteristics of the M2732A are

such that erasure begins when the cells are exposed to light with wavelengths shorter than approximately 4000 Å. It should be noted that sunlight and certain types of fluorescent lamps have wavelengths in the 3000-4000 Å range. Research shows that constant exposure to room level fluorescent lighting could erase a typical M2732A in approximately 3 years, while it would take approximately 1 week to cause erasure when exposed to the direct sunlight. If the M2732A is to be exposed to these types of lighting conditions for extended periods of time, it is suggested that opaque labels be put over the M2732A window to prevent unintentional erasure.

The recommended erasure procedure for the M2732A is exposure to shortwave ultraviolet light which has a wavelength of 2537 Å. The integrated dose (i.e. UV intensity x exposure time) for erasure should be a minimum of 15 W-sec/cm

. The erasure time with this dosage is approximately 15 to 20 minutes using an ultraviolet lamp with 12000 µW/cm

power rating. The M2732A should be placed within 2.5 cm of the lamp tubes during erasure. Some lamps have a filter on their tubes which should be removed before erasure.

Mode E GV

Q0 - Q7

Read V

Data Out

Program VIL Pulse V

Data In

Verify V

Data Out

Program Inhibit V

Hi-Z

Standby V

XVCCHi-Z

Note: X = VIH or VIL.

T ab le 3. Operating Modes

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M2732A

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