This Data Sheet may be revised by subsequent versions

©2004 Eon Silicon Solution, Inc.,

www.eonssi.com

or modifications due to changes in technical specifications.

4

EN25LF20

Rev. D, Issue Date: 2010/05/31

SIGNAL DESCRIPTION

Serial Data Input (DI)

The SPI Serial Data Input (DI) pin provides a means for instructions, addresses and data to be serially

written to (shifted into) the device. Data is latched on the rising edge of the Serial Clock (CLK) input pin.

Serial Data Output (DO)

The SPI Serial Data Output (DO) pin provides a means for data and status to be serially read from

(shifted out of) the device. Data is shifted out on the falling edge of the Serial Clock (CLK) input pin.

Serial Clock (CLK)

The SPI Serial Clock Input (CLK) pin provides the timing for serial input and output operations. ("See

SPI Mode")

Chip Select (CS#)

The SPI Chip Select (CS#) pin enables and disables device operation. When CS# is high the device is

deselected and the Serial Data Output (DO) pin is at high impedance. When deselected, the devices

power consumption will be at standby levels unless an internal erase, program or status register cycle is

in progress. When CS# is brought low the device will be selected, power consumption will increase to

active levels and instructions can be written to and data read from the device. After power-up, CS# must

transition from high to low before a new instruction will be accepted.

Hold (HOLD#)

The HOLD# pin allows the device to be paused while it is actively selected. When HOLD# is brought low,

while CS# is low, the DO pin will be at high impedance and signals on the DI and CLK pins will be

ignored (don’t care). The hold function can be useful when multiple devices are sharing the same SPI

signals.

Write Protect (WP#)

The Write Protect (WP#) pin can be used to prevent the Status Register from being written. Used in

conjunction with the Status Register’s Block Protect (BP0, BP1 and BP2) bits and Status Register

Protect (SRP) bits, a portion or the entire memory array can be hardware protected.

Table 1. PIN Names

Symbol

Pin Name

CLK

Serial Clock Input

DI

Serial Data Input

DO

Serial Data Output

CS#

Chip Enable

WP#

Write Protect

HOLD#

Hold Input

Vcc

Supply Voltage (2.35-3.6V)

Vss

Ground