參數(shù)資料
型號(hào): LTC4053EMSE-4.2#PBF
廠商: LINEAR TECHNOLOGY CORP
元件分類: 電源管理
英文描述: USB Compatible Lithium-Ion Battery Charger with Thermal Regulation; Package: MSOP; No of Pins: 10; Temperature Range: -40°C to +125°C
中文描述: 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO10
封裝: LEAD FREE, PLASTIC, MSOP-10
文件頁數(shù): 16/16頁
文件大?。?/td> 199K
代理商: LTC4053EMSE-4.2#PBF
LTC4053-4.2
9
4053fa
For example, if 500mA charge current is required,
calculate:
RPROG = 1500V/0.5A = 3k
For best stability over temperature and time, 1% metal-
film resistors are recommended.
If the charger is in constant-temperature or constant-
voltage mode, the battery current can be monitored by
measuring the PROG pin voltage as follows:
ICHG = (VPROG / RPROG) 1000
USB and Wall Adapter Power
Although the LTC4053 allows charging from a USB port,
a wall adapter can also be used to charge Li-Ion batteries.
Figure 2 shows an example of how to combine wall adapter
and USB power inputs. A P-channel MOSFET, MP1, is
used to prevent back conducting into the USB port when
a wall adapter is present and Schottky diode, D1, is used
to prevent USB power loss through the 1k pull-down
resistor.
Typically a wall adapter can supply significantly more
current than the 500mA-limited USB port. Therefore, an N-
channel MOSFET, MN1 and an extra 3k program resistor
can be used to increase the charge current to 1A when the
wall adapter is present.
APPLICATIO S I FOR ATIO
WU
U
Undervoltage Lockout (UVLO)
An internal undervoltage lockout circuit monitors the input
voltage and keeps the charger in shutdown mode until VCC
rises above the undervoltage lockout threshold. The UVLO
circuit has a built-in hysteresis of 150mV. Furthermore, to
protect against reverse current in the power MOSFET, the
UVLO circuit keeps the charger in shutdown mode if VCC
falls to within 35mV of the battery voltage. If the UVLO
comparator is tripped, the charger will not come out of
shutdown until VCC rises 70mV above the battery voltage.
Trickle Charge And Defective Battery Detection
At the beginning of a charge cycle, if the battery voltage is
low (below 2.48V) the charger goes into trickle charge
reducing the charge current to 10% of the full-scale
current. If the low battery voltage persists for one quarter
of the total charge time, the battery is assumed to be
defective, the charge cycle is terminated, the CHRG pin
output assumes a high impedance state, and the FAULT
pin pulls low. The fault can be cleared by toggling VCC,
temporarily forcing the SHDN pin to 0V, or temporarily
forcing the BAT pin voltage above 2.48V.
Shutdown
The LTC4053 can be shut down (ICC = 25A) by pulling the
SHDN pin to 0V. For normal operation, pull the SHDN pin
above the manual shutdown threshold voltage level. Do
not leave this pin open. In shutdown the internal linear
regulator is turned off, and the internal timer is reset.
Programming Charge Current
The formula for the battery charge current (see Figure 1)
is:
ICHG = (IPROG) 1000
= (1.5V / RPROG) 1000 or
RPROG = 1500V/ICHG
where RPROG is the total resistance from the PROG pin to
ground. Under trickle charge conditions, this current is
reduced to 10% of the full-scale value.
Figure 2. Combining Wall Adapter and USB Power
4053 F02
1k
3k
Li-Ion
BATTERY
5V WALL
ADAPTER
1A ICHG
3k
LTC4053
BAT
VCC
2
9
7
ICHG
PROG
+
SYSTEM
LOAD
USB
POWER
500mA ICHG
D1
MN1
MP1
相關(guān)PDF資料
PDF描述
LTC4053EMSE-4.2#TRPBF USB Compatible Lithium-Ion Battery Charger with Thermal Regulation; Package: MSOP; No of Pins: 10; Temperature Range: -40°C to +125°C
LTC4054ES5-4.2#TRMPBF Standalone Linear Li-Ion Battery Charger with Thermal Regulation in ThinSOT; Package: SOT; No of Pins: 5; Temperature Range: -40°C to +125°C
LTC4054ES5-4.2#TRPBF Standalone Linear Li-Ion Battery Charger with Thermal Regulation in ThinSOT; Package: SOT; No of Pins: 5; Temperature Range: -40°C to +125°C
LTC4054XES5-4.2#TRMPBF Standalone Linear Li-Ion Battery Charger with Thermal Regulation in ThinSOT; Package: SOT; No of Pins: 5; Temperature Range: -40°C to +125°C
LTC4054LES5-4.2#TRMPBF Standalone Linear Li-Ion Battery Charger with Thermal Regulation in ThinSOT; Package: SOT; No of Pins: 5; Temperature Range: -40°C to +125°C
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LTC4054 制造商:LINER 制造商全稱:Linear Technology 功能描述:Standalone Linear Li-Ion Battery Charger with Thermal Regulation in ThinSOT
LTC4054-4.2 制造商:LINER 制造商全稱:Linear Technology 功能描述:Standalone Linear Li-Ion Battery Charger with Thermal Regulation in ThinSOT
LTC4054ES5-4.2 制造商:Linear Technology 功能描述:Constant Current/Voltage Charger Li-Ion 500mA 4.2V 5-Pin TSOT-23
LTC4054ES54.2#PBF 制造商:Linear Technology 功能描述:
LTC4054ES5-4.2#PBF 制造商:Linear Technology 功能描述:Constant Current/Voltage Charger Li-Ion 500mA 4.2V 5-Pin TSOT-23 制造商:Linear Technology 功能描述:Constant Current/Voltage Charger Li-Ion 500mA 4.2V 5-Pin TSOT-23 Bulk