EUP8020X
CE
Input (Charge Enable)
The
CE
digital input is used to disable or enable the
charge process. A low-level signal on this pin enables the
charge and a high-level signal disables the charge and
places the device in a low-power mode. A high-to-low
transition on this pin also resets all timers and timer fault
conditions. Note that this applies to both AC and USB
charging.
TTE
Input (Timer and Termination Enable)
The
TTE
digital input is used to disable or enable the
fast-charge timer and charge taper detection. A low-level
signal on this pin enables the fast-charge timer and taper
timer and a high-level signal disables this feature. Note
that this applies to both AC and USB charging.
Thermal shutdown and Protection
The EUP8020X monitors the junction temperature, T
J
, of
the die and suspends charging if T
J
exceeds T
(SHTDWN)
.
Charging resumes when T
J
falls below T
(SHTDWN)
by
approximately 30
℃.
TE
Input (Timer Enabled)
Condition #2:
Charge voltage below recharge threshold
(V
(RCH)
) and timeout fault occurs
Recovery method: Under this scenario, the EUP8020X
applies the I
(FAULT)
current. This small current is used to
detect a battery removal condition and remains on as long
as the battery voltage stays below the recharge threshold.
If the battery voltage goes above the recharge threshold,
then the EUP8020X disables the I
(FAULT)
current and
executes the recovery method described for condition #1.
Once the battery falls below the recharge threshold, the
EUP8020X clears the fault and starts a new charge cycle.
A POR or
CE
or
TTE
toggle also clears the fault.
The
TE
digital input is used to disable or enable the
fast-charge timer. A low-level signal on this pin enables
the fast-charge timer and a high-level signal disables this
feature.
Note that this applies to both AC and USB charging.
Timer Fault Recovery
As shown in Figure 3, EUP8020X provides a recovery
method to deal with timer fault conditions. The following
summarizes this method:
Condition #1:
Charge voltage above recharge threshold
(V
(RCH)
) and timeout fault occurs
Recovery method: EUP8020X waits for the battery
voltage to fall below the recharge threshold. This could
happen as a result of a load on the battery, self-discharge
or battery removal. Once the battery falls below the
recharge threshold, the EUP8020X clears the fault and
starts a new charge cycle. A POR or
CE
or
TTE
toggle
also clears the fault.
DS8020X Ver 1.1 June 2006
11
EUTECH [ EUTECH MICROELECTRONICS INC ]
