LTC4058X-4.2_15 Datasheet, PDF (5/12 Pages) Linear Technology – Standalone Linear Li-Ion Battery Charger with Thermal Regulation in DFN

LTC4058-4.2/LTC4058X-4.2
TYPICAL PERFOR A CE CHARACTERISTICS
Charge Current vs Supply Voltage
600
R_PROG = 2k
500
400
V_BAT = V_BSENSE = 4V
300 TA = 25°C
θ_JA = 40°C/W
200
R_PROG = 10k
100
Charge Current
vs Ambient Temperature
600
ONSET OF THERMAL REGULATION
500
R_PROG = 2k
400
V_CC = 5V
300 V_BAT = V_BSENSE = 4V
θ_JA = 40°C/W
200
R_PROG = 10k
100
Recharge Threshold Voltage
vs Temperature
4.16
V_CC = 5V
R_PROG = 10k
4.14
4.12
4.10
4.08
4.06
0
4 4.5 5 5.5 6
V_CC (V)
6.5 7
405842 G13
0
–50 –25
0 25 50 75
TEMPERATURE (°C)
100 125
405842 G14
4.04
–50 –25 0
25 50
TEMPERATURE (°C)
75 100
405842 G15
Power FET Transistor Curve
800
V_CC = 5V
700 ^VBSENSE ^{= 3.5V}
T_A = 25°C
600 ^{RPROG = 2k}
500
400
300
200
100
0
3.8 4.1 4.4 4.7
V_BAT (V)
5
5.3
405842 G16
Power FET “ON” Resistance
vs Temperature
800
V_CC = 5V
V_BAT = 4.8V
700
V_BSENSE = 4V
R_PROG = 2k
600
500
400
300
–50 –25 0
25 50
TEMPERATURE (°C)
75 100
405842 G17
PI FU CTIO S
BSENSE (Pin 1): Battery Sense. This pin is used to Kelvin
sense the positive battery terminal and regulate the final
float voltage to 4.2V. An internal precision resistor divider
sets this float voltage and is disconnected in shutdown
mode. For Li-Ion applications, this pin must be electri-
cally connected to BAT.
BAT (Pin 2): Charge Current Output. Provides charge
current to the battery from the internal P-channel MOSFET.
CHRG (Pin 3): Charge Status Open-Drain Output. When
the battery is charging, the CHRG pin is pulled low by an
internal N-channel MOSFET. When the charge cycle is
completed, CHRG becomes high impedance.
GND (Pins 4, 9): Ground/Exposed Pad. The exposed
backside of the package (Pin 9) is also ground and must
be soldered to the PC board for maximum heat transfer.
PROG (Pin 5): Charge Current Program and Charge Cur-
rent Monitor. Charge current is programmed by connect-
ing a 1% resistor, R_PROG, to ground. When charging in
constant-current mode, this pin servos to 1V. In all modes,
sn405842 405842fs
5