MAX16049 Maxim Integrated Products, MAX16049 Datasheet - Page 53

• Manufacturer Part Number: MAX16049
• Description: (MAX16047 / MAX16049) 12-Channel/8-Channel EEPROM-Programmable System Managers
• Manufacturer: Maxim Integrated Products

www.DataSheet4U.com
LOAD ADDRESS: This is an extension to the standard
IEEE 1149.1 instruction set to support access to the
memory in the MAX16047/MAX16049. When the LOAD
ADDRESS instruction latches into the instruction regis-
ter, TDI connects to TDO through the 8-bit memory
address test data register during the shift-DR state.
READ DATA: This is an extension to the standard IEEE
1149.1 instruction set to support access to the memory
in the MAX16047/MAX16049. When the READ instruc-
tion latches into the instruction register, TDI connects to
TDO through the 8-bit memory read test data register
during the shift-DR state.
WRITE DATA: This is an extension to the standard
IEEE 1149.1 instruction set to support access to the
memory in the MAX16047/MAX16049. When the WRITE
instruction latches into the instruction register, TDI con-
nects to TDO through the 8-bit memory write test data
register during the shift-DR state.
REBOOT: This is an extension to the standard IEEE
1149.1 instruction set to initiate a software controlled
reset to the MAX16047/MAX16049. When the REBOOT
instruction latches into the instruction register, the
MAX16047/MAX16049 resets and immediately begins
the boot-up sequence.
SAVE: This is an extension to the standard IEEE 1149.1
instruction set that triggers a fault log. The current ADC
conversion results along with fault information are
saved to EEPROM depending on the configuration of
the Critical Fault Log Control register (r47h).
SETEXTRAM: This is an extension to the standard IEEE
1149.1 instruction set that allows access to the extend-
ed page. Extended registers include ADC conversion
results, DACOUT enables, and GPIO input/output data.
RSTEXTRAM: This is an extension to the standard IEEE
1149.1 instruction set. Use RSTEXTRAM to return to the
default page and disable access to the extended page.
SETEEPADD: This is an extension to the standard IEEE
1149.1 instruction set that allows access to the EEPROM
page. Once the SETEEPADD command has been sent, all
addresses are recognized as EEPROM addresses only.
RSTEEPADD: This is an extension to the standard IEEE
1149.1 instruction set. Use RSTEEPADD to return to the
default page and disable access to the EEPROM.
When the EEPROM has not been programmed using the
JTAG or I
EN_OUT_ outputs is open-drain active-low. If it is neces-
sary to hold an EN_OUT_ high or low to prevent prema-
System Managers with Nonvolatile Fault Registers
2
12-Channel/8-Channel EEPROM-Programmable
C interface, the default configuration of the
Unprogrammed Device Behavior
Applications Information
______________________________________________________________________________________
ture startup of a power supply before the EEPROM is
programmed, connect a resistor to ground or the supply
voltage. Avoid connecting a resistor to ground if the out-
put is to be configured as open-drain with a separate
pullup resistor.
When V
impedance until V
driven low. All other outputs are high impedance until
V
copied into register memory, and after which the out-
puts assume their programmed states.
Power to the MAX16047/MAX16049 must be main-
tained for a specific period of time to ensure a success-
ful EEPROM fault log operation during a fault that
removes power to the circuit. The amount of time
required depends on the settings in the fault control
register (r47h[1:0]) according to Table 30.
Maintain power for shutdown during fault conditions in
applications where the always-on power supply cannot
be relied upon by placing a diode and a large capaci-
tor between the voltage source, V
15). The capacitor value depends on V
delay required, t
to calculate the capacitor size:
where the capacitance is in Farads and t
in seconds. I
drop across the diode, and V
ple, with a V
t
tance is 100µF.
Table 30. EEPROM Fault Log Operation
Period
REGISTER VALUE
FAULT_SAVE
FAULT CONTROL
CC
r47h[1:0]
reaches 2.85V, when the EEPROM contents are
CC
00
01
10
11
is ramped from 0V, the RESET output is high
of 0.204s, the minimum required capaci-
C
IN
CC(MAX)
=
FAULT_SAVE
of 14V, a diode drop of 0.7V, and a
Device Behavior at Power-Up
t
V
CC
FAULT_SAVE
IN
Failed lines and
ADC values saved
Failed lines saved
ADC values saved
No information
saved
Maintaining Power During a
DESCRIPTION
−
reaches 1.4V, at which point it is
V
is 5mA, V
DIODE
. Use the following formula
UVLO
×
−
V
I
CC(MAX)
CC(MIN)
DIODE
IN
Fault Condition
is 2.85V. For exam-
, and V
t
FAULT_SAVE
IN
is the voltage
FAULT_SAVE
REQUIRED
and the time
PERIOD
CC
204
168
N/A
60
(Figure
(ms)
53
is