- 您现在的位置：买卖IC网 > PDF目录65797 > LTC1734ES6#TR-4.1 (LINEAR TECHNOLOGY CORP) BATTERY CHARGE CONTROLLER, PDSO6 PDF资料下载
参数资料
| 型号： | LTC1734ES6#TR-4.1 |
| 厂商： | LINEAR TECHNOLOGY CORP |
| 元件分类： | 稳压器 |
| 英文描述： | BATTERY CHARGE CONTROLLER, PDSO6 |
| 封装： | PLASTIC, SOT-23, 6 PIN |
| 文件页数： | 6/8页 |
| 文件大小： | 140K |
| 代理商： | LTC1734ES6#TR-4.1 |
6
LTC1734
APPLICATIONS INFORMATION
WU
U
program resistor. The charge current is equal to 1000
(VPROG/RPROG) amps. This feature allows a microcontrol-
ler with an ADC to easily monitor charging current and if
desired, manually shut down the charger at the appropri-
ate time. See Figure 1 for an example. The minimum PROG
pin current is about 3
A (IPROGPU)
Errors in the charge current monitor voltage on the PROG
pin are inversely proportional to battery current and can be
statistically approximated as follows:
One Sigma Error(%)
1 + 0.3/IBAT(A)
Dynamic loads on the battery will cause transients to
appear on the PROG pin. Should they cause excessive
errors in charge current monitoring, a simple RC filter as
shown in Figure 2 can be used to filter the transients. The
filter will also quiet the PROG pin to help prevent inadvert-
ent momentary entry into the manual shutdown mode.
Because the PROG pin is in a closed-loop signal path the
pole frequency must be kept high enough to maintain
adequate AC stability. This means that the maximum
resistance and capacitance presented to the PROG pin
must be limited. See the Stability section for more details.
Constant Current Source
The LTC1734 can be used as a constant current source by
disabling the voltage control loop as shown in Figure 3.
This is done by pulling the BAT pin below the preset float
voltages of 4.1V or 4.2V by grounding the BAT pin. The
program resistor will determine the output current. The
output current range is between approximately 200mA
and 700mA, depending on the maximum power rating of
the external PNP pass transistor.
External PNP Transistor
The external PNP pass transistor must have adequate
beta, low saturation voltage and sufficient power dissipa-
tion capability (including any heat sinking, if required).
To provide 700mA of charge current with the minimum
available base drive of approximately 30mA requires a
PNP beta greater than 23. If lower beta PNP transistors are
used, more base current is required from the LTC1734.
This can result in the output drive current limit being
reached, or thermal shutdown due to excessive power
dissipation. Excessive beta can affect stability (see Stabil-
ity section)
With low input voltages, the PNP saturation voltage
(VCESAT) becomes important. The VCESAT must be less
than the minimum input voltage minus the voltage drop
across the internal sense resistor minus the battery float
voltage. If the PNP transistor can not achieve the low
saturation voltage required, base current will dramatically
increase. This is to be avoided for a number of reasons:
output drive may reach current limit resulting in the
charger’s characteristics to go out of specifications,
excessive power dissipation may force the IC into thermal
shutdown, or the battery could become discharged be-
cause some of the current from the DRIVE pin could be
pulled from the battery through the forward biased collec-
tor base junction.
Figure 2. Logic Control Programming of Output Current to 0mA, 200mA, 500mA or 700mA
Figure 1. Interfacing with a Microcontroller
LTC1734
PROG
C
RPROG
ADC INPUT
1734 F01
OPEN DRAIN
OR TOTEM
POLE OUTPUT
VIN
5V
CHARGE
CURRENT
MONITOR
CHARGE
CURRENT
MONITOR
7.5k
Q2
2N7002
CONTROL 2
FZT549
IBAT
1734 F02
SINGLE
Li-Ion
BATTERY
10
F
GND
PROG
DRIVE
BAT
2
4
6
5
LTC1734
VCC
ISENSE
31
1
F
0.1
F TO
0.5
F
1k
OPTIONAL FILTER
3k
Q1
2N7002
CONTROL 1
CHARGE CURRENT
0
200mA
500mA
700mA
CONTROL 1
LOW
HIGH
CONTROL 2
LOW
HIGH
LOW
HIGH
相关PDF资料 |
PDF描述 |
|---|---|
| LTC201CJ | QUAD 1-CHANNEL, SGL POLE SGL THROW SWITCH, CDIP16 |
| LTC201MJ/883B | QUAD 1-CHANNEL, SGL POLE SGL THROW SWITCH, CDIP16 |
| LTC201CN | QUAD 1-CHANNEL, SGL POLE SGL THROW SWITCH, PDIP16 |
| LTC3830DICE#PBF | SWITCHING CONTROLLER, 250 kHz SWITCHING FREQ-MAX, UUC |
| LTC3830DWF | SWITCHING CONTROLLER, 250 kHz SWITCHING FREQ-MAX, UUC |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC1734LES6-4.2 | 制造商:Linear Technology 功能描述:Battery Charger Li-Ion/NiCD/NiMH 50mA to 180mA 4.2V 6-Pin TSOT-23 |
| LTC1734LES6-4.2#PBF | 制造商:Linear Technology 功能描述:Battery Charger Li-Ion/NiCD/NiMH 50mA to 180mA 4.2V 6-Pin TSOT-23 |
| LTC1734LES6-4.2#TR | 功能描述:IC CHARGER BATT CONSTV/I SOT23-6 RoHS:否 类别:集成电路 (IC) >> PMIC - 电池管理 系列:- 标准包装:61 系列:- 功能:电源管理 电池化学:锂离子（Li-Ion）、锂聚合物（Li-Pol） 电源电压:4.35 V ~ 5.5 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:22-WFDFN 裸露焊盘 供应商设备封装:22-DFN（6x3）裸露焊盘 包装:管件 |
| LTC1734LES6-4.2#TRM | 功能描述:IC CHARGER BATT LIN LI-ION SOT23 RoHS:否 类别:集成电路 (IC) >> PMIC - 电池管理 系列:- 标准包装:2,000 系列:Impedance Track™ 功能:燃料，电量检测计/监控器 电池化学:锂离子（Li-Ion） 电源电压:2.4 V ~ 2.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:20-TSSOP（0.173"，4.40mm 宽） 供应商设备封装:20-TSSOP 包装:带卷 (TR) 产品目录页面:1020 (CN2011-ZH PDF) 配用:BQ27350EVM-ND - BQ27350EVM 其它名称:296-21665-2 |
| LTC1734LES6-4.2#TRMPBF | 功能描述:IC CHARGER BATT LIN LI-ION SOT23 RoHS:是 类别:集成电路 (IC) >> PMIC - 电池管理 系列:- 标准包装:1 系列:- 功能:充电管理 电池化学:锂离子（Li-Ion）、锂聚合物（Li-Pol） 电源电压:3.75 V ~ 6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:SC-74A，SOT-753 供应商设备封装:SOT-23-5 包装:剪切带 (CT) 产品目录页面:669 (CN2011-ZH PDF) 其它名称:MCP73831T-2ACI/OTCT |
发布紧急采购，3分钟左右您将得到回复。