芯美 子
Pin Configurations
Preliminary
EUP8080
Package Type
Pin Configurations
TDFN-10
Pin Description
Pin
PIN
DESCRIPTION
Charge Current Output and Buck Regulator Input. Provides charge current to the
battery and regulates the final float voltage to 4.2V. An internal precision resistor
divider from this pin sets the float voltage and is disconnected in charger shutdown
mode. This pin should be decoupled with a low ESR capacitor for low-noise buck
operation.
1
BAT
Positive Input Supply Voltage. This pin provides power to the battery charger. VCC
can range from 3.75V to 5.5V. This pin should be bypassed with at least a 1ꢀF
capacitor. When VCC is less than 45mV above the BAT pin voltage, the battery
charger enters shutdown mode.
Enable Input Pin for the Battery Charger. Pulling this pin above the manual shutdown
threshold (VIH) puts the EUP8080 charger in shutdown mode, thus stopping the
charge cycle. In battery charger shutdown mode, the EUP8080 has less than 10ꢀA
supply current and less than 5ꢀA battery drain current if the regulator is not running.
Enable is the default state, but the pin should be tied to GND if unused.
2
3
VCC
EN _ CHRG
Charge Current Program and Charge Current Monitor Pin. Connecting a 1% resistor,
RPROG, to ground programs the charge current. When charging in constant-current
mode, this pin servos to 1V. In all modes, the voltage on this pin can be used to
measure the charge current using the following formula :
4
5
PROG
ACPR
V
PROG
I
=
× 400
BAT
R
PROG
Open-Drain Power Supply Status Output. When VCC is greater than the undervoltage
lockout threshold (3.6V) and greater than VBAT 110mV, the ACPR pin will be pulled
to ground; otherwise the pin is high impedance.
Open-Drain Charge Status Output. The charge status indicator pin has three states:
pulldown, high impedance state, and pulse at 2Hz. This output can be used as a logic
interface or as an LED driver. When the battery is being charged, the CHRG pin is
pulled low by an internal N-channel MOSFET. When the charge current drops to
CHRG
6
10% of the full-scale current, the CHRG pin is forced to a high impedance state.
When the battery voltage remains below 2.9V for one quarter of the full charge time,
the battery is considered defective, and the CHRG pin pulses at a frequency of 2Hz
with 75% duty cycle.
DS8080 Ver 0.1 Aug. 2007
2
系 ：15999644579 83151715
EUTECH [ EUTECH MICROELECTRONICS INC ]
