Owner's manual

Preliminary W27L010

Publication Release Date: February 1999

- 3 - Revision A1

Standby Mode

The standby mode significantly reduces VCC current. This mode is entered when

high. In standby

mode, all outputs are in a high impedance state, independent of

and

PGM

Two-line Output Control

Since EPROMs are often used in large memory arrays, the W27L010 provides two control inputs for

multiple memory connections. Two-line control provides for lowest possible memory power

dissipation and ensures that data bus contention will not occur.

System Considerations

EPROM power switching characteristics require careful device decoupling. System designers are

concerned with three supply current issues: standby current levels (Isb), active current levels (Icc),

and transient current peaks produced by the falling and rising edges of

. Transient current

magnitudes depend on the device output's capacitive and inductive loading. Two-line control and

proper decoupling capacitor selection will suppress transient voltage peaks. Each device should have

a 0.1 µF ceramic capacitor connected between its Vcc and GND. This high frequency, low inherent-

inductance capacitor should be placed as close as possible to the device. Additionally, for every eight

devices, a 4.7 µF electrolytic capacitor should be placed at the array's power supply connection

between Vcc and GND. The bulk capacitor will overcome voltage slumps caused by PC board trace

inductances.

TABLE OF OPERATING MODES

VCC = 3.3V, VPP = 12V, VPE = 14V, VHH = 12V, VCP = 5V, X=VIH or VIL

MODE PINS

PGM

A0 A9 VCC VPP OUTPUTS

Read VIL VIL X X X VCC VCC DOUT

Output Disable VIL VIH X X X VCC VCC High Z

Standby (TTL) VIH X X X X VCC VCC High Z

Standby (CMOS)

VCC ±0.3V

X X X X VCC VCC High Z

Program VIL VIH VIL X X VCP VPP DIN

Program Verify VIL VIL VIH X X VCP VPP DOUT

Program Inhibit VIH X X X X VCP VPP High Z

Erase VIL VIH VIL VIL VPE VCP VPE FF (Hex)

Erase Verify VIL VIL VIH X X VCP VPE DOUT

Erase Inhibit VIH X X X X VCP VPE High Z

Product Identifier-

Manufacturer

VIL VIL X VIL VHH VCC VCC DA (Hex)

Product Identifier-device VIL VIL X VIH VHH VCC VCC 01 (Hex)