Electronic Components Datasheet Search |
|
HPA00742DBTR Datasheet(PDF) 10 Page - Texas Instruments |
|
|
HPA00742DBTR Datasheet(HTML) 10 Page - Texas Instruments |
10 / 16 page www.ti.com Charge and Discharge Counting Voltage Current Wake Function Auto Calibration Temperature COMMUNICATIONS SMBus On and Off State SBS Commands bq20z90 SLUS778 – JULY 2007 The integrating delta-sigma ADC measures the charge/discharge flow of the battery by measuring the voltage drop across a small-value sense resistor between the SRP and SRN pins. The integrating ADC measures bipolar signals from -0.25 V to 0.25 V. The bq20z90 detects charge activity when VSR = V(SRP)-V(SRN)is positive and discharge activity when VSR = V(SRP)-V(SRN) is negative. The bq20z90 continuously integrates the signal over time, using an internal counter. The fundamental rate of the counter is 0.65 nVh. The bq20z90 updates the individual series cell voltages through the bq29330 at one second intervals. The bq20z90 configures the bq29330 to connect the selected cell, cell offset, or bq29330 VREF to the CELL pin of the bq29330, which is required to be connected to VIN of the bq20z90. The internal ADC of the bq20z90 measures the voltage, scales it, and calibrates itself appropriately. This data is also used to calculate the impedance of the cell for the Impedance Track™ gas-gauging. The bq20z90 uses the SRP and SRN inputs to measure and calculate the battery charge and discharge current using a 5 m Ω to 20 mΩ typ. sense resistor. The bq20z90 can exit sleep mode, if enabled, by the presence of a programmable level of current signal across SRP and SRN. The bq20z90 provides an auto-calibration feature to cancel the voltage offset error across SRP and SRN for maximum charge measurement accuracy. The bq20z90 performs auto-calibration when the SMBus lines stay low continuously for a minimum of a programmable amount of time. The bq20z90 TS1 and TS2 inputs, in conjunction with two identical NTC thermistors (default are Semitec 103AT), measure the battery environmental temperature. The bq20z90 can also be configured to use its internal temperature sensor. The bq20z90 uses SMBus v1.1 with Master Mode and package error checking (PEC) options per the SBS specification. The bq20z90 detects an SMBus off state when SMBC and SMBD are logic-low for ≥ 2 seconds. Clearing this state requires either SMBC or SMBD to transition high. Within 1 ms, the communication bus is available. Table 1. SBS COMMANDS SBS Cmd Mode Name Format Size in Min Max Default Value Unit Bytes Value Value 0x00 R/W ManufacturerAccess hex 2 0x0000 0xffff — 0x01 R/W RemainingCapacityAlarm unsigned int 2 0 65535 300 mAh or 10mWh 0x02 R/W RemainingTimeAlarm unsigned int 2 0 65535 10 min 0x03 R/W BatteryMode hex 2 0x0000 0xe383 — 0x04 R/W AtRate signed int 2 -32768 32767 — mA or 10mW 0x05 R AtRateTimeToFull unsigned int 2 0 65534 — min 0x06 R AtRateTimeToEmpty unsigned int 2 0 65534 — min 10 Submit Documentation Feedback Copyright © 2007, Texas Instruments Incorporated Product Folder Link(s): bq20z90 Not Recommended for New Designs |
Similar Part No. - HPA00742DBTR |
|
Similar Description - HPA00742DBTR |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |