MAX16048ACB+T Maxim Integrated, MAX16048ACB+T Datasheet - Page 60

• Manufacturer Part Number: MAX16048ACB+T
• Description: Supervisory Circuits 8Ch EEPROM Prob System Manager
• Manufacturer: Maxim Integrated
• Series: MAX16046, MAX16048r

Specifications of MAX16048ACB+T

• Rohs: yes

Set the DACOUT_ range bits (see the DAC Outputs
section) such that V
within the DACOUT range. Set R
control the DAC has on the output voltage of the power
supply. Large values of R
degree of resolution control over the output voltage,
and small values of R
resolution control. Be sure to respect the minimum and
maximum output voltages that the DC-DC converter is
capable of generating.
The following is an example that illustrates the use of
the formulas for calculating the margin up and margin
down values. This example uses a generic 3.3V DC-DC
converter with a trim input. Below are the margin up
and margin down formulas taken from the data sheet
for the power supply:
By inspecting these formulas, V
1kΩ, and R
to 1.6V to fit the reference voltage. The output voltage
of the DC-DC converter is 3.3V; therefore the ratio (1 +
R
Set R
(increase R
values into the equations for the output voltage:
For V
V
ages correspond with a margin down limit of -17.6%
and a margin up limit of 15.2%. Since the reference
voltage is not exactly in the center of the DACOUT_
range, the margin limits are not symmetrical. To
decrease the margin limits, increase the value of R
Power to the MAX16046/MAX16048 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 36.
12-Channel/8-Channel EEPROM-Programmable
System Managers with Nonvolatile Fault Registers
60
1
DACOUT_
V
TRIM DOWN:R
TRIM U
/R
OUT
2
) = V
5
=
DACOUT_
(
P P :R
to zero to use the widest trim range possible
2.69
ADJ_UP
OUT
)
4
5
⎛
⎝ ⎜
= 1.6V, V
1k
Maintaining Power During a Fault
= 1kΩ. Set the DACOUT_ range from 0.8V
to decrease the trim range). Insert these
ADJ_DOWN
Ω
/V
×
REF
V
=
DACOUT
= 0.8V, V
⎛
⎝ ⎜
V
= 3.3/1.225 = 2.69.
OUT_NOM
2k
OUT
REF
5
=
Ω
correspond to lesser degree of
+
⎛
⎝ ⎜
1k
100
∆
1.225 %
falls approximately halfway
= 3.80V. These output volt-
%
Ω
×
−
5
1.225
OUT
(100
2 k
∆
⎞
⎠ ⎟
correspond to higher
( )
5
⎞
⎠ ⎟
Ω
+
to vary the amount of
REF
=
= 2.72V, and for
∆
(
%)
2
. . 69
= 1.225V, R
−
)
100 2
(
V
DACOUT_
Condition
∆
+
%
∆ ∆
2
%
+
⎞
⎠ ⎟
1.225
( )
5
k
.
Ω
3
=
)
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
18). 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 127µF.
Figure 17. Connections for Margining Using Trim Input Method
Table 36. EEPROM Fault Log Operation
Period
FAULT_SAVE
REGISTER VALUE
FAULT CONTROL
r47h[1:0]
00
01
10
11
V
R
REF
DC-DC OR LDO
3
CC(MAX)
of 0.204s, the minimum required capaci-
C
IN
=
of 14V, a diode drop of 0.7V, and a
FAULT_SAVE
t
FAULT_SAVE
V
IN
Failed lines and
ADC values saved
Failed lines saved
ADC values saved
No information
saved
R
4
−
is 6.5mA, V
R
R
DESCRIPTION
1
2
V
TRIM
DIODE
OUT
. Use the following formula
UVLO
×
−
I
CC(MAX)
V
R
5
UVLO
DIODE
IN
is 2.85V. For exam-
, and V
IN
FAULT_SAVE
is the voltage
t
MAX16046
MAX16048
REQUIRED
FAULT_SAVE
and the time
PERIOD
CC
V
(ms)
DACOUT_
204
168
60
—
(Figure
is