- 您现在的位置：买卖IC网 > PDF目录44989 > LTC2942IDCB#TRPBF (LINEAR TECHNOLOGY CORP) POWER SUPPLY SUPPORT CKT, PDSO6 PDF资料下载
参数资料
| 型号： | LTC2942IDCB#TRPBF |
| 厂商： | LINEAR TECHNOLOGY CORP |
| 元件分类： | 电源管理 |
| 英文描述： | POWER SUPPLY SUPPORT CKT, PDSO6 |
| 封装： | 2 X 3 MM, LEAD FREE, PLASTIC, MO-229, DFN-6 |
| 文件页数： | 2/18页 |
| 文件大小： | 227K |
| 代理商： | LTC2942IDCB#TRPBF |
LTC2942
10
2942fa
applicaTions inFormaTion
Alert/Charge Complete Configuration B[2:1]
The AL/CC pin is a dual function pin configured by the
control register. By setting bits B[2:1] to [10] (default)
the AL/CC pin is configured as an alert pin following the
SMBus protocol. In this configuration the AL/CC pin is a
digital output and is pulled low if one of the three mea-
sured quantities (charge, voltage, temperature) exceeds
its high or low threshold or if the value of the accumulated
chargeregisteroverflowsorunderflows.Analertresponse
procedure started by the master resets the alert at the
AL/CC pin. For further information see the Alert Response
Protocol section.
SettingthecontrolbitsB[2:1]to[01]configurestheAL/CC
pin as a digital input. In this mode, a high input on the
AL/CC pin communicates to the LTC2942 that the battery
is full and the accumulated charge register is set to its
maximum value FFFFh. The AL/CC pin would typically
be connected to the “charge complete” output from the
battery charger circuitry.
If neither the alert nor the charge complete functionality
is desired, bits B[2:1] should be set to [00]. The AL/CC
pin is then disabled and should be tied to GND.
Avoid setting B[2:1] to [11] as it enables the alert and the
charge complete modes simultaneously.
Choosing RSENSE
To achieve the specified precision of the coulomb counter,
the differential voltage between SENSE+ and SENSE– must
stay within ±50mV. For differential input signals up to
±300mV the LTC2942 will remain functional but the preci-
sion of the coulomb counter is not guaranteed.
The required value of the external sense resistor, RSENSE,
is determined by the maximum input range of VSENSE and
the maximum current of the application:
R
mV
I
SENSE
MAX
≤
50
The choice of the external sense resistor value influences
the gain of the coulomb counter. A larger sense resistor
gives a larger differential voltage between SENSE+ and
SENSE–forthesamecurrentwhichresultsinmoreprecise
coulombcounting.Thustheamountofchargerepresented
bytheleastsignificantbit(qLSB)oftheaccumulatedcharge
(registers C, D) is equal to:
qLSB =0.085mAh
50m
RSENSE
M
128
or
qLSB =0.085mAh
50m
RSENSE
when the prescaler is set to its default value of M = 128.
Note that 1mAh = 3.6C (coulomb).
Choosing RSENSE = 50mV/IMAX is not sufficient in ap-
plications where the battery capacity (QBAT) is very large
compared to the maximum current (IMAX):
QBAT > IMAX 5.5 Hours
For such low current applications with a large battery,
choosing RSENSE according to RSENSE = 50mV/IMAX can
lead to a qLSB smaller than QBAT/216 and the 16-bit accu-
mulated charge register may underflow before the battery
is exhausted or overflow during charge. Choose, in this
case, a maximum RSENSE of:
RSENSE ≤
0.085mAh 216
QBAT
50m
In an example application where the maximum current is
IMAX = 100mA, calculating RSENSE = 50mV/IMAX would
lead to a sense resistor of 500mΩ. This gives a qLSB of
8.5Ahandtheaccumulatedchargeregistercanrepresent
a maximum battery capacity of QBAT = 8.5Ah 65535 =
557mAh. If the battery capacity is larger, RSENSE must be
lowered. For example, RSENSE must be reduced to 150mΩ
if a battery with a capacity of 1800mAh is used.
相关PDF资料 |
PDF描述 |
|---|---|
| LTC2942CDCB#TRPBF | POWER SUPPLY SUPPORT CKT, PDSO6 |
| LTC2990CMS#PBF | 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO10 |
| LTC2990CMS#TR | 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO10 |
| LTC2990IMS#PBF | 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO10 |
| LTC2990IMS | 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO10 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC2943CDD#PBF | 制造商:Linear Technology 功能描述:IC GAS GAUGE MULTICELL 8DFN 制造商:Linear Technology 功能描述:BATTERY GAS GAUGE, 20V, DFN-8, Battery Management Function:Fuel Gauge, Battery Type:-, Supply Voltage Min:3.6V, Supply Voltage Max:20V, Battery IC Case Style:DFN, No. of Pins:8, IC Interface Type:I2C, SMBus, Package / Case:8-DFN , RoHS Compliant: Yes |
| LTC2943CDD#TRPBF | 制造商:Linear Technology 功能描述:BATTERY GAS GAUGE, 20V, DFN-8, Battery Management Function:Fuel Gauge, Supply Voltage Min:3.6V, Supply Voltage Max:20V, Battery IC Case Style:DFN, No. of Pins:8, IC Interface Type:I2C, SMBus, Operating Temperature Min:0C , RoHS Compliant: Yes |
| LTC2945CMS#PBF | 制造商:Linear Technology 功能描述: 制造商:Linear Technology 功能描述:IC POWER MONITOR I2C 12-MSOP 制造商:Linear Technology 功能描述:MS-System Monitor/Other, Wide Range I2C Power Monitor (SDAO) |
| LTC2945CMS#TRPBF | 制造商:Linear Technology 功能描述:IC POWER MONITOR I2C 12-MSOP 制造商:Linear Technology 功能描述:MS-System Monitor/Other, Wide Range I2C Power Monitor (SDAO) |
| LTC2945CMS-1#PBF | 制造商:Linear Technology 功能描述:I2C Power Monitor 12-Pin MSOP 制造商:Linear Technology 功能描述:IC POWER MONITOR I2C 12-MSOP |
发布紧急采购，3分钟左右您将得到回复。