MAX6897PAZT+T Maxim Integrated Products, MAX6897PAZT+T Datasheet - Page 11

• Manufacturer Part Number: MAX6897PAZT+T
• Description: Supervisory Circuits Adjustable Sequencer/Supervisor
• Manufacturer: Maxim Integrated Products

Specifications of MAX6897PAZT+T

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

The exact value of the pullup resistors for the open-
drain outputs is not critical, but some consideration
should be made to ensure the proper logic levels when
the device is sinking current. For example, if V
2.25V and the pullup voltage is 28V, you would try to
keep the sink current less than 0.5mA as shown in the
Electrical Characteristics table. As a result, the pullup
resistor should be greater than 56kΩ. For a 12V pullup,
the resistor should be larger than 24kΩ. It should be
noted that the ability to sink current is dependent on the
V
Figures 8, 9, 10 show typical applications for the
MAX6895–MAX6899. Figure 8 shows the MAX6895
Figure 8. Overvoltage Protection
CC
0 TO 28V
supply voltage.
R1
R2
IN
______________________________________________________________________________________
ENABLE
Typical Application Circuits
MAX6897
GND
3.3V ALWAYS ON
Pullup Resistor Values
CDELAY
(MAX6897/MAX6898)
V
CC
OUT
Sequencing/Supervisory Circuits
R
PULLUP
P
CC
=
Ultra-Small, Adjustable
used with a p-channel MOSFET in an overvoltage pro-
tection circuit. Figure 9 shows the MAX6895 in a low-
voltage sequencing application using an n-channel
MOSFET. Figure 10 shows the MAX6895 used in a mul-
tiple-output sequencing application.
In higher power applications, using an n-channel device
reduces the loss across the MOSFETs as it offers a
lower drain-to-source on-resistance. However, an n-
channel MOSFET requires a sufficient V
fully enhance it for a low R
Figure 9 shows the MAX6895 in a switch sequencing
application using an n-channel MOSFET.
Similarly, if a higher voltage is present in the system, the
open-drain version can be used in the same manner.
Figure 9. Low-Voltage Sequencing Using an n-Channel MOSFET
Using an n-Channel Device for Sequencing
MONITORED
3.3V
R2
R1
IN
ENABLE
MAX6895
GND
5V BUS
CDELAY
DS_ON
V
CC
OUT
1.2V INPUT
. The application in
C
GS
CDELAY
N
voltage to
1.2V OUTPUT
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