Rainbow Electronics MAX16043 - Manual (Page 10)

MAX16041/MAX16042/MAX16043
The following equation is provided to help estimate the
value of the resistors based on the amount of acceptable
error:
where e A is the fraction of the maximum acceptable
absolute resistive divider error attributable to the input
leakage current (use 0.01 for ±1%), V
INTH is the voltage
at which the output (OUT_) should assert, and I L is the
worst-case IN_ leakage current (see the Electrical
Characteristics ). Calculate R2 as follows:
Unused Inputs
Connect any unused IN_ and EN_ inputs to V CC .
OUT_ Output
The MAX16041/MAX16042/MAX16043 feature open-drain
outputs. An OUT_ goes low when its respective IN_ input
voltage drops below its specified threshold or when its
EN_ goes low (see Table 1). OUT_ goes high when EN_
is high and V
IN_ is above its threshold after a time delay.
Open-drain outputs require an external pullup resistor to
any voltage from 0 to 28V.
RESET Output
RESET asserts low when any of the monitored voltages
(IN_) falls below its respective threshold, any EN_ goes
low, or
MR is asserted. RESET remains asserted for the
reset timeout period after all of the monitored voltages
exceed their respective thresholds, all EN_ are high, all
OUT_ are high, and
MR is deasserted. All devices have
a push-pull, active-low reset output.
R
V R
V V
TH
INTH TH
2
1
=
×
−
R
e V
I
A INTH
L
1
=
×
Dual-/Triple-/Quad-Voltage, Capacitor-
Adjustable, Sequencing/Supervisory Circuits
10 ______________________________________________________________________________________
IN_
V TH
V INTH
R1 = R2 x
( ) V INTH
V TH
R1
R2
MAX16041
MAX16042
MAX16043
-1
Figure 3. Setting the Adjustable Input
Table 1. Output State*
EN_ IN_ OUT_
Low V IN_ < V TH Low
High V IN_ < V TH Low
Low V IN_ > V TH Low
High V IN_ > V TH OUT_ = high impedance
* When V CC falls below the UVLO, all outputs go low regardless
of the state of EN_ and V IN_ . The outputs are guaranteed to be
in the correct state for V CC down to 1.2V.
Table 2. Input-Voltage Threshold Selector
TH1/TH0
LOGIC
IN1 (ALL
VERSIONS)
(V)
IN2 (ALL
VERSIONS)
(V)
IN3
(MAX16042)
(V)
IN4
(MAX16043)
(V)
Low/Low 3.3 2.5 1.8 1.5
Low/High 3.3 1.8 Adj Adj
Low/Open 3.3 1.5 Adj Adj
High/Low 3.3 1.2 1.8 2.5
High/High 2.5 1.8 Adj Adj
High/Open 3.3 Adj 2.5 Adj
Open/Low 3.3 Adj Adj Adj
Open/High 2.5 Adj Adj Adj
Open/Open Adj Adj Adj Adj