adm1069ast-reel Analog Devices, Inc., adm1069ast-reel Datasheet - Page 27

• Manufacturer Part Number: adm1069ast-reel
• Description: Super Sequencer With Margining Control
• Manufacturer: Analog Devices, Inc.

UPDATING THE SEQUENCING ENGINE
Sequencing engine (SE) functions are not updated in the same
way as regular configuration latches. The SE has its own
dedicated 512-byte EEPROM for storing state definitions,
providing 63 individual states with a 64-bit word each (one state
is reserved). At power-up, the first state is loaded from the SE
EEPROM into the engine itself. When the conditions of this
state are met, the next state is loaded from EEPROM into the
engine, and so on. The loading of each new state takes approxi-
mately 10 μs.
To alter a state, the required changes must be made directly to
EEPROM. RAM for each state does not exist. The relevant
alterations must be made to the 64-bit word, which is then
uploaded directly to EEPROM.
INTERNAL REGISTERS
The ADM1069 contains a large number of data registers. The
principal registers are the address pointer register and the
configuration registers.
Address Pointer Register
This register contains the address that selects one of the other
internal registers. When writing to the ADM1069, the first byte
of data is always a register address that is written to the address
pointer register.
Configuration Registers
These registers provide control and configuration for various
operating parameters of the ADM1069.
(V
POWER-UP
EEPROM
CC
> 2.5V)
M
E
E
P
R
O
L
D
CONTROLLER
Figure 34. Configuration Update Flow Diagram
D
A
A
T
DEVICE
SMBus
LATCH A
Rev. A | Page 27 of 36
M
R
A
L
D
U
P
D
EEPROM
The ADM1069 has two 512-byte cells of nonvolatile, electrically
erasable, programmable read-only memory (EEPROM), from
Register Address 0xF800 to Register Address 0xFBFF. The
EEPROM is used for permanent storage of data that is not lost
when the ADM1069 is powered down. One EEPROM cell
contains the configuration data of the device; the other contains
the state definitions for the SE. Although referred to as read-
only memory, the EEPROM can be written to, as well as read
from, via the serial bus in exactly the same way as the other
registers.
The major differences between the EEPROM and other
registers are as follows:
•
•
•
The first EEPROM is split into 16 (0 to 15) pages of 32 bytes
each. Page 0 to Page 6, starting at Address 0xF800, hold the
configuration data for the applications on the ADM1069 (such
as the SFDs and PDOs). These EEPROM addresses are the same
as the RAM register addresses, prefixed by F8. Page 7 is
reserved. Page 8 to Page 15 are for customer use.
Data can be downloaded from EEPROM to RAM in one of the
following ways:
•
•
An EEPROM location must be blank before it can be
written to. If it contains data, it must first be erased.
Writing to EEPROM is slower than writing to RAM.
Writing to the EEPROM should be restricted, because it
has a limited write/cycle life of typically 10,000 write
operations due to the usual EEPROM wear-out
mechanisms.
At power-up, when Page 0 to Page 6 are downloaded.
By setting Bit 0 of the UDOWNLD register (0xD8), which
performs a user download of Page 0 to Page 6.
LATCH B
(OV THRESHOLD
FUNCTION
ON VP1)
ADM1069