- 您现在的位置：买卖IC网 > PDF目录1833 > LTC4012IUF-3#TRPBF (Linear Technology)IC CTLR BATT CHARGER CC/CV 20QFN PDF资料下载
参数资料
| 型号： | LTC4012IUF-3#TRPBF |
| 厂商： | Linear Technology |
| 文件页数： | 19/28页 |
| 文件大小： | 0K |
| 描述： | IC CTLR BATT CHARGER CC/CV 20QFN |
| 标准包装： | 2,500 |
| 功能： | 充电管理 |
| 电池化学： | 多化学 |
| 电源电压： | 6 V ~ 28 V |
| 工作温度： | -40°C ~ 125°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 20-WFQFN 裸露焊盘 |
| 供应商设备封装： | 20-QFN 裸露焊盘（4x4） |
| 包装： | 带卷 (TR) |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页当前第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页
LTC4012-3
APPLICATIONS INFORMATION
100 mV – ?
? R 1 ?
I LIM
The overall accuracy of this circuit needs to be better
than the power source current tolerance or be margined
such that the worse-case error remains under the power
source limits.
The accuracy of the Figure 7 circuit is a function of the
INTV DD , V BE , R CL , R F , R1 and R3 tolerances. To improve
accuracy, the tolerance of R F should be changed from
5.1k, 5% to a 2.49k 1% resistor. R CL and the programming
resistors R1 and R3 should also be 1% tolerance such
that the dominant error is INTV DD (±3%). Bias resistor R2
can be 5%. When choosing NPN transistors, both need
to have good gain (>100) at 10μA levels. Low gain NPNs
will increase programming errors. Q1 must be a matched
NPN pair. Since R F has been reduced in value by half, the
capacitor value of C F should double to 0.22μF to remain
effective at filtering out any noise.
If you wish to reduce R CL power dissipation for a given
current limit, the programming equation becomes:
? 5 ? 2 . 49 k ?
R CL =
If you wish to make the input current limit programmable,
the equation becomes:
In many notebook applications, there are situations
where two different I LIM values are needed to allow two
different power adapters or power sources to be used.
In such cases, start by setting R LIM for the high power
I LIM configuration and then use Figure 7 to set the lower
I LIM value. To toggle between the two I LIM values, take
the three ground connections shown in Figure 7, combine
them into one common connection and use a small-signal
NFET (2N7002) to open or close that common connec-
tion to circuit ground. When the NFET is off, the circuit
is defeated (floating) allowing I LIM to be the maximum
value. When the NFET is on, the circuit will become active
and I LIM will drop to the lower set value.
Monitoring Charge Current
The PROG pin voltage can be used to indicate charge cur-
rent where 1.2085V indicates full programmed current (1C)
and zero charge current is approximately equal to R PROG ?
11.67μA. PROG voltage varies in direct proportion to the
charge current between this zero-current (offset) value and
1.2085V. When monitoring the PROG pin voltage, using a
buffer amplifier as shown in Figure 8 will minimize charge
current errors. The buffer amplifier may be powered from
the INTV DD pin or any supply that is always on when the
charger is on.
100 mV – ?
I LIM =
? 5 ? 2 . 49 k ?
?
? R 1 ?
R CL
INTV DD 17
LTC4012-3
The equation governing R2 for both applications is based
on the value of R1. R3 should always be equal to R1.
PROG 13
<30nA
4012-3 F08
TO SYSTEM
MONITOR
R2 = 0.875 ? R1
Figure 8. PROG Voltage Buffer
40123fb
相关PDF资料 |
PDF描述 |
|---|---|
| LTC4050EMS-4.1#TR | IC BATT CHRG CNTRL LI-ION 10MSOP |
| LTC4052EMS8E-4.2#TRPBF | IC CHARGER PULSE LI-ION 8-MSOP |
| LTC4053EDD-4.2#TRPBF | IC CHARGER BATTERY USB 10-DFN |
| LTC4054ES5-4.2#TRMPBF | IC CHARGR BATTERY L-ION TSOT23-5 |
| LTC4055EUF-1#TRPBF | IC USB PWR MNGR BATT CHRGR 16QFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC4020EUHF#PBF | 制造商:Linear Technology 功能描述:Battery Charger Lead-Acid/Li-FePO4/Li-Ion/Li-Pol 20000mA 55V 38-Pin QFN EP 制造商:Linear Technology 功能描述:IC BATT CHARGER 55V BB 38QFN 制造商:Linear Technology 功能描述:BATTERY CHARGER, 20A, QFN-38 制造商:Linear Technology 功能描述:BATTERY CHARGER, 20A, QFN-38, Input Voltage:55V, Battery Charge Voltage:55V, Charge Current Max:20A, Battery IC Case Style:QFN, No. of Pins:38, No. of Series Cells:12, Operating Temperature Min:-40C, Operating Temperature Max:125C , RoHS Compliant: Yes |
| LTC4020EUHF#TRPBF | 制造商:Linear Technology 功能描述:Battery Charger Lead-Acid/Li-FePO4/Li-Ion/Li-Pol 20000mA 55V 38-Pin QFN EP T/R 制造商:Linear Technology 功能描述:IC BATT CHARGER 55V BB 38QFN 制造商:Linear Technology 功能描述:BATTERY CHARGER, 20A, QFN-38, Input Voltage:55V, Battery Charge Voltage:55V, Charge Current Max:20A, Battery IC Case Style:QFN, No. of Pins:38, No. of Series Cells:12, Operating Temperature Min:-40C, Operating Temperature Max:125C , RoHS Compliant: Yes |
| LTC4020IUHF#PBF | 制造商:Linear Technology 功能描述:Battery Charger Lead-Acid/Li-FePO4/Li-Ion/Li-Pol 20000mA 55V 38-Pin QFN EP 制造商:Linear Technology 功能描述:IC BATT CHARGER 55V BB 38QFN 制造商:Linear Technology 功能描述:BATTERY CHARGER, 20A, QFN-38 制造商:Linear Technology 功能描述:BATTERY CHARGER, 20A, QFN-38, Input Voltage:55V, Battery Charge Voltage:55V, Charge Current Max:20A, Battery IC Case Style:QFN, No. of Pins:38, No. of Series Cells:12, Operating Temperature Min:-40C, Operating Temperature Max:125C , RoHS Compliant: Yes |
| LTC4020IUHF#TRPBF | 制造商:Linear Technology 功能描述:Battery Charger Lead-Acid/Li-FePO4/Li-Ion/Li-Pol 20000mA 55V 38-Pin QFN EP T/R 制造商:Linear Technology 功能描述:IC BATT CHARGER 55V BB 38QFN 制造商:Linear Technology 功能描述:BATTERY CHARGER, 20A, QFN-38, Input Voltage:55V, Battery Charge Voltage:55V, Charge Current Max:20A, Battery IC Case Style:QFN, No. of Pins:38, No. of Series Cells:12, Operating Temperature Min:-40C, Operating Temperature Max:125C , RoHS Compliant: Yes |
| LTC4050 | 制造商:LINEAR 制造商全称:LINEAR 功能描述:Standalone 250mA Li-Ion Battery Charger in 2 × 2 DFN |
发布紧急采购，3分钟左右您将得到回复。