ISD2540 datasheet(13/42 Pages) WINBOND

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ISD2532/40/48/64

M6 – Push-Button Mode

The ISD2500 series contain a Push-Button Operational Mode. The Push-Button Mode is used

primarily in very low-cost applications and is designed to minimize external circuitry and components,

thereby reducing system cost. In order to configure the device in Push-Button Operational Mode, the

two most significant address bits must be HIGH, and the M6 mode pin must also be HIGH. A device in

this mode always powers down at the end of each playback or record cycle after CE goes HIGH.

When this operational mode is implemented, three of the pins on the device have alternate

functionality as described in the table below.

TABLE 3: ALTERNATE FUNCTIONALITY IN PINS

Pin Name

Alternate Functionality in Push-Button Mode

Start/Pause Push-Button (LOW pulse-activated)

Stop/Reset Push-Button (HIGH pulse-activated)

EOM

Active-HIGH Run Indicator

(START/PAUSE)

In Push-Button Operational Mode, CE acts as a LOW-going pulse-activated START/PAUSE signal.

If no operation is currently in progress, a LOW-going pulse on this signal will initiate a playback or

record cycle according to the level on the P/ R pin. A subsequent pulse on the CE pin, before an

EOM

is reached in playback or an overflow condition occurs, will pause the current operation, and

the address counter is not reset. Another CE pulse will cause the device to continue the operation

from the place where it is paused.

PD (STOP/RESET)

In Push-Button Operational Mode, PD acts as a HIGH-going pulse-activated STOP/RESET signal.

When a playback or record cycle is in progress and a HIGH-going pulse is observed on PD, the

current cycle is terminated and the address pointer is reset to address 0, the beginning of the

message space.

EOM

(RUN)

In Push-Button Operational Mode, EOM becomes an active-HIGH RUN signal which can be used to

drive an LED or other external device. It is HIGH whenever a record or playback operation is in

progress.

Recording in Push-Button Mode

1. The PD pin should be LOW, usually using a pull-down resistor.

Publication Release Date: June 2003

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Revision 1.0

ISD2540 Datasheet(PDF) 13 Page - Winbond