M50LPW040

6/36

Supply Signal Descriptions

The Supply Signals are the same for both interfac-

es.

supplies the power for all operations (Read, Pro-

gram, Erase etc.).

Supply Voltage is less than the Lockout Voltage,

accidentally damaging the data during power up,

power down and power surges. If the Program/

Erase Controller is programming or erasing during

this time then the operation aborts and the

memory contents being altered will be invalid.

is reset to Read mode.

A 0.1µF capacitor should be connected between

pin to decouple the current surges from the power

connected to the power supply. The PCB track

widths must be sufficient to carry the currents

required during program and erase operations.

Supply Voltage pin is used to select the Fast

Program (see the Quadruple Byte Program

Command description) and Fast Erase options of

performed and an error is reported in the Status

Register if an attempt to change the memory

Erase operations take place as normal. When

Program Command is performed) and Fast Erase

operations are used. Any other voltage input to

not be used.

hours during the life of the memory.

age measurements.

BUS OPERATIONS

The two interfaces have similar bus operations but

the signals and timings are completely different.

The Low Pin Count (LPC) Interface is the usual

interface and all of the functionality of the part is

available through this interface. Only a subset of

functions are available through the Address/

Address Multiplexed (A/A Mux) Interface.

Follow the section Low Pin Count (LPC) Bus

Operations below and the section Address/

Address Multiplexed (A/A Mux) Interface Bus

Operations below for a description of the bus

operations on each interface.

Low Pin Count (LPC) Bus Operations

The Low Pin Count (LPC) Interface consists of

four data signals (LAD0-LAD3), one control line

(LFRAME)

and

a

clock

(CLK).

In

addition

protection against accidental or malicious data

corruption can be achieved using two further

signals (TBL and WP). Finally two reset signals

(RP and INIT) are available to put the memory into

a known state.

The data signals, control signal and clock are

designed to be compatible with PCI electrical

specifications. The interface operates with clock

speeds up to 33MHz.

The following operations can be performed using

the appropriate bus cycles: Bus Read, Bus Write,

Standby, Reset and Block Protection.

Note: 1. Except for the rating "Operating Temperature Range", stresses above those listed in the Table "Absolute Maximum Ratings" may

cause permanent damage to the device. These are stress ratings only and operation 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 Rating condi-

tions for extended periods may affect device reliability. Refer also to the STMicroelectronics SURE Program and other relevant qual-

ity documents.

and for less than 20ns during transitions.

Symbol

Parameter

Value

Unit

Ambient Operating Temperature (Temperature Range Option 1)

0 to 70

°C

Ambient Operating Temperature (Temperature Range Option 5)

–20 to 85

°C

Temperature Under Bias

–50 to 125

°C

Storage Temperature

–65 to 150

°C

(2)

Input or Output Voltage

V

Supply Voltage

–0.6 to 4

V

Program Voltage

–0.6 to 13

V