uP8001A/B
Functional Description
The uP8001 is a highly integrated single-cell Li-ion or Li- When this pin is released from ground, the uP8001 is
Polymer batter charger specifically designed to work with activated according to settings and battery status. Logic
AC adaptor or USB port.
high of ENpin also enables the 2.8V bias voltage for biasing
the internal control and logic circuit. This voltage also
provides current for external circuits such asNTC thermistor
circuit. The maximum allowed external load for 2V8 is 2mA.
The uP8001 charges battery with a minimum current when
the battery voltage is lower than 2.8V. The charger works at
constant current mode when the battery voltage is between
2.8V and 4.2V, the charge current is programmable up to Charge Cycle
2A by an external resistor. The charger works at constant
A charge cycle can be initiated by anyone of the following
voltage mode when the battery voltage is 4.2V. When the
input voltage is removed, the uP8001 automatically enters
a low quiescent current sleep mode, dropping the battery
drain current to 1uA.
events:
- power on reset,
- the EN pin is toggled from low to high,
Other features include thermal foldback charge current,NTC - a new battery is inserted (detected by TEMP pin),
thermistor interface and automatic recharge. The uP8001
is available in thermal-enhanced and space-saving VQFN
completing a charge cycle,
and VDFNpackages.
- the battery voltage drops below a recharge threshold after
- recovery from an battery over-temperature or under-
temperature fault,
Power On Reset (POR)
The input voltage is continuously monitored for power on
A charge cycle consists of three charge modes: trickle mode
reset (POR). The uP8001 resets itself as the input voltage
(TKM), constant current mode (CCM), and constant voltage
rises above the POR rising threshold, typically 3.4V. The
mode (CVM) as shown in Figure 1.
device shuts down if the input voltage is under its POR
Trickle Mode
falling threshold, typically 2.4V, and draws less than 1uA
A charge cycle always starts with the trickle mode where
minimum charging current is used. T1 and T6 indicate the
starting of charge cycle that are initiated by VIN POR and
recharge threshold respectively. The uP8001 leaves TKM
and enters CCM at T2 and T7 if the battery voltage stays
above VMIN (2.8V typical) for 15 consequently cycles of the
internal oscillator. The uP8001 enters TKM and the 15-cycle
counter is reset whenever the battery voltage drops below
quiescent current from the battery.
Chip Enable and 2.8V Bias Voltage
The EN pin is internally pulled high to VIN pin for chip disable/
enable. Pulling this pin to ground shuts down the uP8001
and disables the 2.8V bias voltage. When shut down, the
charge draws typically less than 30uAcurrent from the input
power and less than 1uAform the battery.
VIN
POR Rising
Threshold
2V8
Charge Cycle
Charge Cycle
STAT#
EN
15 cycle ~
15 cycles
VRECHG
1/8 TOUT
VBAT
VMIN
IMIN
ICHG
T0
T1
T2
T3 T4
T5
T6
T7
T8
T9 T10
Figure 1. Typical Charge Cycles of uP8001.
uPI Semiconductor Corp., http://www.upi-semi.com
Rev. F00, File Name: uP8001A/B-DS-F0002
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