CAT25C128PI-1.8TE13 Ver la hoja de datos (PDF) - Catalyst Semiconductor => Onsemi

Número de pieza

componentes Descripción

Fabricante

CAT25C128PI-1.8TE13

128K/256K-Bit SPI Serial CMOS E2PROM

Catalyst Semiconductor => Onsemi 

CAT25C128/256

DEVICE OPERATION

Write Enable and Disable

The CAT25C128/256 contains a write enable latch. This

latch must be set before any write operation. The device

powers up in a write disable state when Vcc is applied.

WREN instruction will enable writes (set the latch) to the

device. WRDI instruction will disable writes (reset the

latch) to the device. Disabling writes will protect the

device against inadvertent writes.

READ Sequence

The part is selected by pulling CS low. The 8-bit read

instruction is transmitted to the CAT25C128/256, fol-

lowed by the 16-bit address (the Most Significant Bit is

don’t care for 25C256 and the two most significant bits

are don't care for the 25C128).

After the correct read instruction and address are sent,

the data stored in the memory at the selected address is

shifted out on the SO pin. The data stored in the memory

at the next address can be read sequentially by continu-

ing to provide clock pulses. The internal address pointer

is automatically incremented to the next higher address

after each byte of data is shifted out. When the highest

address (7FFFh for 25C256 and 3FFFh for 25C128) is

reached, the address counter rolls over to 0000h allow-

ing the read cycle to be continued indefinitely. The read

operation is terminated by pulling the CS high. To read

the status register, RDSR instruction should be sent.

The contents of the status register are shifted out on the

SO line. The status register may be read at any time

even during a write cycle.Read sequence is illustrated in

figure 4. Reading status register is illustrated in figure 5.

Figure 2. WREN Instruction Timing

CS

SK

SI

0 0 0 0 0 1 10

SO

Note: Dashed Line= mode (1, 1) — — — —

HIGH IMPEDANCE

Figure 3. WRDI Instruction Timing

CS

SK

SI

0 0 0 0 0 1 00

SO

Note: Dashed Line= mode (1, 1) — — — —

HIGH IMPEDANCE

7

Doc. No. 25088-00 1/01

Share Link: