|
|
PDF LTC4085-4 Data sheet ( Hoja de datos )
| Número de pieza | LTC4085-4 | |
| Descripción | USB Power Manager | |
| Fabricantes | Linear | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de LTC4085-4 (archivo pdf) en la parte inferior de esta página. Total 24 Páginas | ||
|
No Preview Available !
LTC4085-3/LTC4085-4
FEATURES
USB Power Manager with
Ideal Diode Controller and
3.95V Li-Ion Charger
DESCRIPTION
■ Seamless Transition Between Input Power Sources:
Li-Ion/Polymer Battery, USB and 5V Wall Adapter
■ 215mΩ Internal Ideal Diode Plus Optional External
Ideal Diode Controller Provide Low Loss PowerPath™
When Wall Adapter/USB Input Not Present
■ Load Dependent Charging Guarantees Accurate
USB Input Current Compliance
■ 3.95V Float Voltage Improves Battery Life Span and
High Temperature Safety Margin
■ Constant-Current/Constant-Voltage Operation with
Thermal Feedback to Maximize Charging Rate without
Risk of Overheating*
■ Selectable 100% or 20% Input Current Limit
(e.g., 500mA/100mA)
■ Battery Charge Current Independently Programmable
Up to 1.2A
■ Automatic Output Undervoltage Charge Current
Reduction (LTC4085-3)
■ Tiny (4mm × 3mm × 0.75mm) 14-Lead DFN Package
APPLICATIONS
■ Portable USB Devices
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
Bat-Track, PowerPath and ThinSOT are trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners. Protected by U.S. Patents, including
6522118, 6700364. Other patents pending.
The LTC®4085-3/LTC4085-4 is a USB power manager
and Li-Ion/Polymer battery charger designed for portable
battery-powered applications. The part controls the total
current used by the USB peripheral for operation and
battery charging. The total input current can be limited to
20% or 100% of a programmed value up to 1.5A (typically
100mA or 500mA). Battery charge current is automati-
cally reduced such that the sum of the load current and
charge current does not exceed the programmed input
current limit.
The LTC4085-3/LTC4085-4 includes a complete constant-
current/constant-voltage linear charger for single cell Li-Ion
batteries. These 3.95V versions of the standard LTC4085
are intended for applications which have extended battery
lifetime requirements or those that require high temperature
(approximately >60°C) operation or storage. Under these
conditions, a reduced float voltage will trade-off initial cell
capacity for the benefit of increased capacity retention
over the life of the battery. A reduced float voltage also
minimizes swelling in prismatic and polymer cells, and
avoids open CID (pressure fuse) in cylindrical cells.
The LTC4085-3/LTC4085-4 also includes a programmable
termination timer, automatic recharging, an end-of-charge
status output and an NTC thermistor.
TYPICAL APPLICATION
5V WALL
ADAPTER
INPUT
5V (NOM)
FROM USB
CABLE VBUS
IIN
4.7μF SUSPEND USB POWER
100mA 500mA SELECT
IN
SUSP
WALL
ACPR
HPWR
OUT
LTC4085-3/
PROG LTC4085-4 GATE
CLPROG
BAT
NTC CHRG
VNTC
10k
GND TIMER
100k 2k
10k
ILOAD
TO LDOs,
REGs, ETC
1k 4.7μF
510Ω
*
IBAT
+
0.1μF
* OPTIONAL - TO LOWER
IDEAL DIODE IMPEDANCE
408534 TA01
Input and Battery Current vs Load Current
RPROG = 100k, RCLPROG = 2k
600
IIN
500
400
ILOAD
300
200 IBAT
(CHARGING)
100
0
WALL = 0V
–100
0 100 200
IBAT
(DISCHARGING)
300 400 500
600
ILOAD (mA)
408534 TA01b
408534fb
1
1 page  
LTC4085-3/LTC4085-4
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C unless otherwise noted.
Input Supply Current
vs Temperature
900
VIN = 5V
800 VBAT = 3.95V
RPROG = 100k
700 RCLPROG = 2k
600
500
400
300
200
100
0
–50
–25 0 25 50
TEMPERATURE (°C)
75 100
408534 G01
Input Supply Current vs
Temperature (Suspend Mode)
70
VIN = 5V
60
VBAT = 3.95V
RPROG = 100k
RCLPROG = 2k
50 SUSP = 5V
40
30
20
10
0
–50 25
0 25 50
TEMPERATURE (°C)
75 100
408534 G02
Battery Drain Current
vs Temperature
(BAT Powers OUT, No Load)
100 VIN = 0V
90 VBAT = 3.95V
80
70
60
50
40
30
20
10
0
–50 –25
0
25 50 75 100
TEMPERATURE (°C)
408534 G03
Input Current Limit
vs Temperature, HPWR = 5V
525
VIN = 5V
VBAT = 3.7V
515
RPROG = 100k
RCLPROG = 2k
505
495
485
475
–50 –25
0
25 50
TEMPERATURE (°C)
75 100
408534 G04
Input Current Limit
vs Temperature, HPWR = 0V
110
VIN = 5V
108 VBAT = 3.7V
106
RPROG = 100k
RCLPROG = 2k
104
102
100
98
96
94
92
90
–50 –25
0
25 50 75 100
TEMPERATURE (°C)
408534 G05
CLPROG Pin Voltage
vs Temperature
1.2
VIN = 5V
RCLPROG = 2k
1.0
HPWR = 5V
0.8
0.6
0.4
HPWR = 0V
0.2
0
–50 –25 0
25 50
TEMPERATURE (°C)
75 100
408534 G06
PROG Pin Voltage
vs Temperature
1.020
1.015
1.010
VIN = 5V
VBAT = 3.80V
RPROG = 100k
RCLPROG = 2k
1.005
1.000
0.995
0.990
0.985
0.980
–50 –25 0
25 50 75 100
TEMPERATURE (°C)
408534 G07
VFLOAT Load Regulation
4.05
RPROG = 34k
4.00
3.95
3.90
3.85
3.80
3.75
0 200 400 600 800 1000
IBAT (mA)
408534 G08
Battery Regulation (Float)
Voltage vs Temperature
3.970 VIN = 5V
3.965 IBAT = 2mA
3.960
3.955
3.950
3.945
3.940
3.935
3.930
–50 –25
0
25 50 75
TEMPERATURE (°C)
100
408534 G09
408534fb
5
5 Page 
LTC4085-3/LTC4085-4
OPERATION
The LTC4085 is a complete PowerPath controller for bat-
tery powered USB applications. The LTC4085 is designed
to receive power from a USB source, a wall adapter, or a
battery. It can then deliver power to an application con-
nected to the OUT pin and a battery connected to the
BAT pin (assuming that an external supply other than the
battery is present). Power supplies that have limited cur-
rent resources (such as USB VBUS supplies) should be
connected to the IN pin which has a programmable current
limit. Battery charge current will be adjusted to ensure that
the sum of the charge current and load current does not
exceed the programmed input current limit.
An ideal diode function provides power from the battery
when output/load current exceeds the input current limit or
when input power is removed. Powering the load through
the ideal diode instead of connecting the load directly to
the battery allows a fully charged battery to remain fully
charged until external power is removed. Once external
power is removed the output drops until the ideal diode is
forward biased. The forward biased ideal diode will then
provide the output power to the load from the battery.
Furthermore, powering switching regulator loads from the
OUT pin (rather than directly from the battery) results in
shorter battery charge times. This is due to the fact that
switching regulators typically require constant input power.
When this power is drawn from the OUT pin voltage (rather
than the lower BAT pin voltage) the current consumed
by the switching regulator is lower leaving more current
available to charge the battery.
The LTC4085 also has the ability to receive power from
a wall adapter. Wall adapter power can be connected to
the output (load side) of the LTC4085 through an exter-
nal device such as a power Schottky or FET, as shown in
Figure 1. The LTC4085 has the unique ability to use the
output, which is powered by the wall adapter, as a path
to charge the battery while providing power to the load. A
wall adapter comparator on the LTC4085 can be configured
to detect the presence of the wall adapter and shut off the
connection to the USB to prevent reverse conduction out
to the USB bus.
408534fb
11
11 Page | ||
| Páginas | Total 24 Páginas | |
| PDF Descargar | [ Datasheet LTC4085-4.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| LTC4085-1 | USB Power Manager |  Linear Technology |
| LTC4085-3 | USB Power Manager | Linear Technology |
| LTC4085-3 | USB Power Manager | Linear |
| LTC4085-4 | USB Power Manager | Linear |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |