MAX14525 Datasheet, PDF (6/7 Pages) Maxim Integrated Products – Battery Switch with Four Enable Inputs

Battery Switch with Four Enable Inputs
Pin Description
PIN
NAME
FUNCTION
1
BAT
Lithium-Ion (Li+) Battery Connection
2
JIG
Enable Input with Standard Logic Threshold
3
ON_K Enable Input with Accurate Threshold (+3.0V)
4
S_EN Enable Input with Standard Logic Threshold Logically ANDed with IN
5
GND Ground
6
TA
Enable Input with High Threshold
7, 8
IN
Power Switch Input. The power switch input voltage range is from +2.2V to +5.5V. Connect a 0.1µF
capacitor from IN to GND. Connect pins 7 and 8 together for proper operation.
—
EP
Exposed Pad. Connect EP to ground. Do not use EP as the only ground connection.
Detailed Description
The MAX14525 features a low 35mΩ (typ) R_ON load
switch with four unique enable inputs. The MAX14525
can be used to disconnect the lithium-ion battery from
the loads in portable devices such as cell phones. It
operates from a +2.2V to +5.5V supply voltage.
The MAX14525 features an ultra-low 0.8µA (typ) quies-
cent supply current to maximize battery life in portable
devices. The device is enabled from four possible
inputs: external charge connection travel adapter (TA),
on key (ON_K), factory mode enable (JIG), and switch
enable (S_EN). The S_EN input is internally ANDed with
the switched battery connection (IN).
TA Input
The TA input on the MAX14525 can be connected
directly to the external charger source. The TA input is
high-voltage capable (+28V max) and features a high
threshold voltage to limit false voltage trips, and an
input resistance of 100kΩ (typ) to ground.
ON_K Input
The ON_K line is active high and is pulled up to the
lithium-ion battery through a momentary push button
switch. This input features an accurate voltage detec-
tor threshold which does not enable the load switch
until the battery threshold is above +3.0V ±2%. When
the battery has a very low charge and the on key is
pressed, the accurate threshold does not allow the
phone to boot up.
JIG Input
The JIG input on the MAX14525 is a logic-level input
(+1.8V compatible) from an external source to indicate
the device has been connected to a factory cable. This
signal requires a standard logic-input threshold voltage
(+1.4V high).
S_EN Input
The S_EN input on the MAX14525 is a logic-level input
(+1.8V compatible) from an external source used to
hold the switch on when the triggering condition (TA,
ON_K, or JIG) is removed. The standard logic thresh-
old voltage comes from the host microprocessor that
pulls S_EN high once the code has begun running on
the microprocessor. The S_EN input is internally
ANDed with the voltage on IN. The IN connection to the
AND gate thresholds are standard CMOS values of 1/3
and 2/3 of V_BAT.
Chip Information
PROCESS: CMOS
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