Z86C02/E02/L02

Zilog

DS96DZ80301

P R E L I M I N A R Y

15

1

LOW NOISE VERSION

Low EMI Emission

The Z8 can be programmed to operate in a Low EMI emis-

sion mode by means of a mask ROM bit option (Z86C02)

or OTP bit option (Z86E02). Use of this feature results in:

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All pre-driver slew rates reduced to 10 ns typical.

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Internal SCLK/TCLK operation limited to a maximum of

4 MHz - 250 ns cycle time.

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Output drivers have resistances of 200 ohms (typical).

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Oscillator divide-by-two circuitry eliminated.

The Low EMI mode is mask-programmable to be selected

by the customer at the time the ROM Code is submitted

(for Z86C02 only).

PRECAUTION

Stack pointer register (SPL) at FFHex and general purpose register at FEHex are set to 00Hex after reset.

PIN FUNCTIONS

OTP Programming Mode

D7-D0 Data Bus. Data can be read from, or written to the

EPROM through this data bus.

and 6.4V during the other modes (Program, Program Ver-

ify, etc.).

/CE Chip Enable (active Low). This pin is active during

EPROM Read Mode, Program Mode, and Program Verify

Mode.

/OE Output Enable (active Low). This pin drives the Data

Bus direction. When this pin is Low, the Data Bus is output.

When High, the Data Bus is input. This pin must toggle for

each data output read.

EPM EPROM Program Mode. This pin controls the differ-

ent EPROM Program Modes by applying different

voltages.

age.

Clear Clear (active High). This pin resets the internal ad-

dress counter at the High Level.

Clock Address Clock. This pin is a clock input. The internal

address counter increases by one with one clock cycle.

/PGM Program Mode (active Low). A Low level at this pin

programs the data to the EPROM through the Data Bus.

Application Precaution

The production test-mode environment may be enabled

accidentally during normal operation if excessive noise

In addition, processor operation of Z8 OTP devices may be

/EPM, /OE pins while the microcontroller is in Standard

Mode.

Recommendations for dampening voltage surges in both

test and OTP mode include the following:

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Adding a capacitor to the affected pin.