Rainbow Electronics MAX16043 - Manual (Page 9)

MAX16041/MAX16042/MAX16043
Dual-/Triple-/Quad-Voltage, Capacitor-
Adjustable, Sequencing/Supervisory Circuits
_______________________________________________________________________________________ 9
Applications Information
Tolerance
The MAX16041/MAX16042/MAX16043 feature a pin-
selectable threshold tolerance. Connect TOL to GND to
select the thresholds 5% below the nominal value.
Connect TOL to V
CC to select the threshold tolerance
10% below the nominal voltage. Do not leave TOL uncon-
nected.
Adjustable Input
These devices offer several monitoring options with both
fixed and/or adjustable reset thresholds (see Table 2).
For the adjustable threshold inputs, the threshold voltage
(V
TH
) at each adjustable IN_ input is typically 0.5V (TOL
= GND) or 0.472V (TOL = V CC ). To monitor a voltage
V INTH , connect a resistive divider network to the circuit as
shown in Figure 3 and use the following equation to cal-
culate the threshold voltage:
Choosing the proper external resistors is a balance
between accuracy and power use. The input to the volt-
age monitor is a high-impedance input with a small
100nA leakage current. This leakage current contributes
to the overall error of the threshold voltage where the out-
put is asserted. This induced error is proportional to the
value of the resistors used to set the threshold. With lower
value resistors, this error is reduced, but the amount of
power consumed in the resistors increases.
V V
R
R
INTH TH
= × +
⎛
⎝⎜ ⎞
⎠⎟
1
1
2
Figure 2. Timing Diagram (CDLY_ Open)
V CC
V
TH
V
TH
t < t
ON
V UVLO
t
ON
t
RP
t DELAY-
t DELAY+
t
RST_DELAY
t OFF
t RP t RP
t ON
IN_
EN_
OUT_
RESET