UBA2007 View Datasheet(PDF) - Philips Electronics
Part Name
Description
Manufacturer
UBA2007 Datasheet PDF : 19 Pages
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Philips Semiconductors
Charge switch
Product specification
UBA2007
CUR
MOD
SW
MOD
REV
MOD
HIGH
TEMP
HIGH
BAT
CHGOK_N
VBAT
> 3.1 V
MODE
H
H
H
no
no
L
H
H
H
no
no
H
H
H
H
no
no
H
X REVERSE and
SLOW and FAST
CHARGE
yes REVERSE and
SLOW and FAST
CHARGE
no REVERSE and
SLOW and FAST
CHARGE
Notes
1. X = don’t care;
L = LOW voltage level;
H = HIGH voltage level.
2. Currents in the other direction are blocked.
FUNCTION
switch low
ohmic
CURRENT
DIRECTION(2)
charger to
battery
switch low
ohmic
battery to
charger
switch high none
ohmic
7.2 OFF mode
In the OFF mode the current path between charger and
battery is fully switched off. In addition all internal circuitry
is switched off. The battery is not loaded by the UBA2007
in this situation.
The OFF mode is entered if:
• SWMOD, CURMOD and REVMOD are LOW.
• REVMOD is LOW and CHGOK_N is HIGH.
7.3 SHUTDOWN mode
The SHUTDOWN mode corresponds to switching off the
charging path between the pins BAT and CHG. The circuit
will enter the SHUTDOWN mode in the following cases:
• Overvoltage detected on pin BAT
• Undervoltage detected on pin BAT while in REVERSE
mode
• Overheat detected on the die.
In the case of overvoltage shutdown, the state is latched
internally and can be reset only by disconnecting the
charger wall plug.
7.4 SLOW CHARGE mode
In the SLOW CHARGE mode a constant current is applied
to the battery. SLOW CHARGE mode is entered when the
SWMOD and REVMOD input pins are made LOW, pin
CURMOD is HIGH, the charger input voltage is at least
2.5 V and VCHG > VBAT.
The SLOW CHARGE mode is stopped when the voltage
on the BAT pin increases above the maximum battery
voltage or when a too high die temperature occurs.
7.5 FAST CHARGE mode
In the FAST CHARGE mode the switch (see Fig.1) is
turned on slowly by the internal circuitry. The FAST
CHARGE mode is entered when the SWMOD input signal
is HIGH.
The current through the switch is monitored by the current
limiting circuit. When this current exceeds the predefined
current limit, it is kept constant by reducing the drive
voltage of the switch.
The current limit is adjustable, from 50 mA to 2 A, through
an external resistor connected to the RLIMF pin. The
voltage on RLIMF is proportional to the current flowing
through the switch (see Section 11.3).
The FAST CHARGE mode is stopped when the voltage on
the BAT pin increases above the maximum battery voltage
or when a too high die temperature occurs.
Attention: RLIMF cannot trim the current limit while in
SLOW CHARGE or REVERSE modes.
Remark: The dissipation inside the UBA2007 will increase
strongly when the current limitation is activated, this might
lead to activation of the thermal protection.
2003 Oct 01
7
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