- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄385273 > DS2782 (Maxim Integrated Products, Inc.) Stand-Alone Fuel Gauge IC PDF資料下載
參數(shù)資料
| 型號： | DS2782 |
| 廠商： | Maxim Integrated Products, Inc. |
| 英文描述： | Stand-Alone Fuel Gauge IC |
| 中文描述： | 獨立式電量計IC |
| 文件頁數(shù)： | 10/25頁 |
| 文件大小： | 291K |
| 代理商： | DS2782 |
DS2782: Stand-Alone Fuel Gauge IC
10 of 25
CURRENT MEASUREMENT CALIBRATION
The DS2782’s current measurement gain can be adjusted through the RSGAIN register, which
is factory-calibrated
to meet the data sheet specified accuracy. RSGAIN is user accessible and can be reprogrammed after module or
pack manufacture to improve the current measurement accuracy. Adjusting RSGAIN can correct for variation in an
external sense resistor’s nominal value, and allows the use of low-cost, non-precision current sense resistors.
RSGAIN is an 11 bit value stored in 2 bytes of the Parameter EEPROM Memory Block. The RSGAIN value adjusts
the gain from 0 to 1.999 in steps of 0.001 (precisely 2
-10
). The user must program RSGAIN cautiously to ensure
accurate current measurement. When shipped from the factory, the gain calibration value is stored in two separate
locations in the Parameter EEPROM Block, RSGAIN which is reprogrammable and FRSGAIN which is read only.
RSGAIN determines the gain used in the current measurement. The read-only FRSGAIN is provided to preserve
the factory value only and is not used in the current measurement.
SENSE RESISTOR TEMPERATURE COMPENSATION
The DS2782 is capable of temperature compensating the current sense resistor to correct for variation in a sense
resistor’s value over temperature. The DS2782 is factory programmed with the sense resistor temperature
coefficient, RSTC, set to zero, which turns off the temperature compensation function. RSTC is user accessible
and can be reprogrammed after module or pack manufacture to improve the current accuracy when using a high
temperature coefficient current-sense resistor. RSTC is an 8-bit value stored in the Parameter EEPROM Memory
Block. The RSTC value sets the temperature coefficient from 0 to +7782ppm/oC in steps of 30.5ppm/oC. The user
must program RSTC cautiously to ensure accurate current measurement.
Temperature compensation adjustments are made when the Temperature register crosses 0.5
o
C boundaries. The
temperature compensation is most effective with the resistor placed as close as possible to the VSS terminal to
optimize thermal coupling of the resistor to the on-chip temperature sensor. If the current shunt is constructed with
a copper PCB trace, run the trace under the DS2782 package if possible.
CURRENT ACCUMULATION
Current measurements are internally summed, or accumulated, at the completion of each conversion period with
the results displayed in the Accumulated Current Register (ACR). The accuracy of the ACR is dependent on both
the current measurement and the conversion timebase. The ACR has a range of 0 to 409.6mVh with an LSb of
6.25 Vh. Additional read-only registers (ACRL) hold fractional results of each accumulation to avoid truncation
errors. Accumulation of charge current above the maximum register value is reported at the maximum register
value (7FFFh); conversely, accumulation of discharge current below the minimum register value is reported at the
minimum value (8000h).
Charge currents (positive Current register values) less than 100 V are not accumulated in order to mask the effect
of accumulating small positive offset errors over long periods. This limits the minimum charge current, for coulomb-
counting purposes, to 5mA for RSNS = 0.020 and 20mA for RSNS = 0.005 .
Read and write access is allowed to the ACR. The ACR must be written MSByte first then LSByte. Whenever the
ACR is written, the fractional accumulation result bits are cleared. The write must be completed within 3.515s (one
ACR register update period). A write to the ACR forces the ADC to perform an offset correction conversion and
update the internal offset correction factor. Current measurement and accumulation begins with the second
conversion following a write to the ACR. Writing ACR clears the fractional values in ACRL. The Format of the ACR
register is shown in Figure 8, and the format of ACRL is shown in Figure 9.
In order to preserve the ACR value in case of power loss, the ACR value is backed up to EEPROM. The ACR
value is recovered from EEPROM on power-up. See the Memory Map in Table 2 for specific address location and
backup frequency.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| DS3234 | Extremely Accurate SPI Bus RTC with Integrated Crystal and SRAM |
| DS3234S | Extremely Accurate SPI Bus RTC with Integrated Crystal and SRAM |
| DS3234SN | Extremely Accurate SPI Bus RTC with Integrated Crystal and SRAM |
| DS33Z11 | Ethernet Mapper |
| DS33ZH11 | Ethernet Mapper |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| DS2782_09 | 制造商:MAXIM 制造商全稱:Maxim Integrated Products 功能描述:Stand-Alone Fuel Gauge IC |
| DS2782BE | 制造商:Maxim Integrated Products 功能描述:STAND ALONE FG IC 2WIRE 8P TSSOP - Rail/Tube |
| DS2782BE/T&R | 制造商:Maxim Integrated Products 功能描述:STAND ALONG FG IC 2WIRE 8P TSSOP TR - Tape and Reel |
| DS2782E+ | 功能描述:電池管理 Stand-Alone Fuel Gauge RoHS:否 制造商:Texas Instruments 電池類型:Li-Ion 輸出電壓:5 V 輸出電流:4.5 A 工作電源電壓:3.9 V to 17 V 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:VQFN-24 封裝:Reel |
| DS2782E+R | 制造商:MAXIM 制造商全稱:Maxim Integrated Products 功能描述:Stand-Alone Fuel Gauge IC |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。