Datasheet

11XX
DS22067J-page 6  2011 Microchip Technology Inc.
2.0 FUNCTIONAL DESCRIPTION
2.1 Principles of Operation
The 11XX family of serial EEPROMs support the
UNI/O
®
protocol. They can be interfaced with
microcontrollers, including Microchip’s PIC
®
microcon-
trollers, ASICs, or any other device with an available
discrete I/O line that can be configured properly to
match the UNI/O protocol.
The 11XX devices contain an 8-bit instruction register.
The devices are accessed via the SCIO pin.
Table 4-1 contains a list of the possible instruction
bytes and format for device operation. All instructions,
addresses, and data are transferred MSb first, LSb
last.
Data is embedded into the I/O stream through
Manchester encoding. The bus is controlled by a
master device which determines the clock period, con-
trols the bus access and initiates all operations, while
the 11XX works as slave. Both master and slave can
operate as transmitter or receiver, but the master
device determines which mode is active.
FIGURE 2-1: BLOCK DIAGRAM
SCIO
STATUS
Register
I/O Control
Memory
Control
Logic
X
Dec
HV Generator
EEPROM
Array
Page Latches
Y Decoder
Sense Amp.
R/W Control
Logic
Vcc
Vss
Current-
Limited
Slope
Control