MAX4960 Maxim Integrated Products, MAX4960 Datasheet - Page 7

• Manufacturer Part Number: MAX4960
• Description: (MAX4959 / MAX4960) High-Voltage OVP with Battery Switchover
• Manufacturer: Maxim Integrated Products

only if the backup capacitor on V
maintain power for greater than the 10ms blanking time.
The detection that the adapter is unplugged and
plugged in again is implemented by monitoring the V
signal. The adapter is unplugged when V
V
greater than V
this lower threshold, an external storage capacitor at the
V
below 4V, power for some internal V
ry is supplied by the external capacitor at the V
IN
DD
=~ 0.75V, and it is plugged in when V
pin is necessary. When the input voltage V
OVS
UVS
V
DD
High-Voltage OVP with Battery Switchover
IN
=~ 0.75V. To ensure the monitoring of
MAX4960
_______________________________________________________________________________________
IN
N
VREF2 = 0.7V
VREF1 = 2V
DD
IN
is large enough to
monitoring circuit-
+
-
+
-
IN
+
-
drops below
IN
V
SG
SOURCE1
becomes
IN
DD
POWER
drops
UVLO
V
ON
DD
pin.
IN
BANDGAP
OFF STORAGE
POWER-ON
RESET AND
ANALOG
SUPPLY
This capacitor is supplied by V
internally limited to 5.5V.
When the input voltage V
turned off automatically and P1 does not turn on again
until the adapter is unplugged (V
plugged in again. When the adapter is not present, P1 is
kept off with the gate-source resistor (which is internal for
the MAX4960 and external for the MAX4959), and the
CB pin controls the battery switchover pFET P2.
+
-
Functional Diagrams (continued)
DIGITAL
SUPPLY
Functional Diagram for the MAX4960
+
-
GATE1
N1
UVLOINT
OVLO
Adapter Not Present (V
+
-
IN
UVLO
LOGIC
drops below 4.4V, P1 is
IN
through a diode and is
IN
N2
<~0.75V) and
GATE2
GND
CB
IN
< V
UVLO
7
)