Datasheet

bq24278
www.ti.com SLUSB04 –JUNE 2012
THERMAL INFORMATION
bq24278
THERMAL METRIC
(1)
UNITS
YFF (48 PINS) QFN (24 PINS)
θ
JA
Junction-to-ambient thermal resistance 49.8 32.6
θ
JCtop
Junction-to-case (top) thermal resistance 0.2 30.5
θ
JB
Junction-to-board thermal resistance 1.1 3.3
°C/W
ψ
JT
Junction-to-top characterization parameter 1.1 0.4
ψ
JB
Junction-to-board characterization parameter 6.6 9.3
θ
JCbot
Junction-to-case (bottom) thermal resistance N/A 2.6
spacer
(1) For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
RECOMMENDED OPERATING CONDITIONS
MIN MAX UNITS
IN voltage range 4.2 18
(1)
V
IN
V
IN operating range 4.2 10
I
IN
Input current IN input 2.5 A
I
SYS
Ouput Current from SW, DC 3 A
Charging 2.5
I
BAT
A
Discharging, using internal battery FET 2.5
T
J
Operating junction temperature range 0 125 ºC
(1) The inherent switching noise voltage spikes should not exceed the absolute maximum rating on either the BOOT or SW pins. A tight
layout minimizes switching noise.
ELECTRICAL CHARACTERISTICS
Circuit of Figure 2, VU
VLO
< V
IN
< V
OVP
AND V
IN
>V
BAT
+V
SLP
, T
J
= 0°C–125°C and T
J
= 25°C for typical values (unless
otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
V
UVLO
< V
IN
< V
OVP
AND V
IN
> V
BAT
+V
SLP
PWM
15 mA
switching
I
IN
Input quiescent current V
UVLO
< V
IN
< V
OVP
AND V
IN
> V
BAT
+V
SLP
PWM NOT
5
switching
0°C < T
J
< 85°C, High-Z Mode 175 μA
I
BATLEAK
Leakage current from BAT to the supply 0°C< T
J
< 85°C, V
BAT
= 4.2V, V
IN
= 0 V 5 μA
0°C< T
J
< 85°C, V
BAT
= 4.2 V, V
IN
= 0 V or 5 V,
Battery discharge current in High Impedance mode (BAT,
I
BAT_HIZ
55 μA
SW, SYS)
High-Z Mode
POWER PATH MANAGEMENT
V
SYS(REG)
V
BAT
< V
MINSYS
3.6 3.7 3.82
System regulation voltage V
V
SYSREGFETOFF
Battery FET turned off, Charge disable or termination 4.26 4.33 4.37
V
MINSYS
Minimum system regulation voltage V
BAT
< V
MINSYS
, Input current limit or VINDPM active 3.4 3.5 3.62 V
V
BAT
–
V
BSUP1
Enter supplement mode threshold V
BAT
> 2.5 V V
40mV
V
BAT
–
V
BSUP2
Exit supplement mode threshold V
BAT
> 2.5 V V
10mV
I
LIM(Discharge)
Current limit, discharge or supplement mode Current monitored in internal FET only 7 A
Measured from (V
BAT
– V
SYS
) = 300 mV to
Deglitch time, OUT short circuit during discharge or
t
DGL(SC1)
250 μs
supplement mode
V
BGATE
= (VBAT – 600 mV)
Recovery time, OUT short circuit during discharge or
t
REC(SC1)
60 ms
supplement mode
Battery range for BGATE operation 2.5 4.5 V
Copyright © 2012, Texas Instruments Incorporated Submit Documentation Feedback 3
Product Folder Link(s) :bq24278