Features

Completely integrated 2 series, 3 series, and 4 series lithium ion or lithium polymer battery packagers and protection

advanced compensation release terminal Voltage (CEDV) measurement

high-side N-CH protection FET driver

Integrated charging field effect transistor

Integrated integrated integrated Unit balanced

Low power consumption mode

- Low power: lt; 180μA

- Sleep lt; 76μA

A full set of programmable protection functions

- voltage

- current

- temperature

complex charging algorithm

- Jeita

- Enhanced charging

- Adaptive charging

Support the dual-line SMBUS V1.1 interface

Sha- 1 Identity verification

Compact packaging: 38 lead TSSOP

Notebook/Internet version

Medicalcare And test device

Portable instrument

Description

Texas Instruments

BQ3050

Compensation Endof Discharge Voltage (CEDV) gas measuring instrument and battery pack The manager is a single -chip solution that provides rich protection, certification and data collection functions for the 2 series, 3 series and 4 series battery lithium ions and lithium polymer battery packs.

The BQ3050 device uses its integrated high -performance simulation peripheral equipment, measures and maintains the accurate record of capacity, voltage, current, temperature, and other key parameters in lithium ion batteries or lithium polymer batteries, and via SMBUS V1 The compatible interface reports this information to the main controller of the system.

BQ3050 provides software -based first -level and second -level security protection, which is used for overvoltage, under pressure, ultra -temperature and over -charging conditions, as well as hardware -based discharge current and short circuit protection.

SHA-1 identity verification has a safety memory for verifying the key, and can undoubtedly identify the genuine battery pack.

The compact 38 lead TSSOP package minimizes the cost and size of the solution of smart batteries, and provides the maximum functionality and security for the battery measurement application.

Equipment information

(1), please refer to the ordering appendix at the end of the data table.

Jane Figure

(1), when any clock low electric When flat exceeding TTIMEOUT, the BQ3050 timeout.

(2), Thigh, the maximum value is the shortest time of the bus. For T GT; 50 μs, SMBC 1 will cause any transaction reset to BQ3050 involved in the progress. When the height of the thigh is 0, this specification is effective. If thigh_val 1, the value of the thigh is set by thigh_1,2, and the timeout is not the SMBUS standard.

(3), Tlow: Sext is the cumulative time that allows the clock cycle from the beginning to stop extending the clock cycle from the beginning to the device.

(4), Tlow: MEXT is the cumulative time that allows the main device to stop extending the clock cycle from the beginning to stopping the clock cycle in a message.

(5), the rise time TR Vilmax – 0.15) to (vihmin+0.15).

(6), the decrease time TF 0.9 VDD to (Vilmax -0.15).

Typical features

Detailed description

Overview

BQ3050 measurement voltage measurement voltage , Temperature and current to determine the battery capacity and charging status (SOC). BQ3050 monitors charging and discharge activities through sensors between SRP and SRN pins and the voltage between small resistors (5 MΩ to 20 MΩ, typical values) connected to the battery. By integrating the charge of the battery, adjust the battery SOC during the battery charging or discharge process. The measurement of OCV and charge points has determined chemical SOC.

QMAX is valued at the number of data tables from the battery manufacturer by the number of parallel batteries and used to calculate the design capacity. It uses OCV and QMAX values to determine the Stateofcharge () of battery insertion, device resetting or executing commands. FullChargeCapAcity () reports the learning capacity from completely charging until voltage () reaches EDV0 threshold. When the voltage () drops below the shutdown, the voltage is turned off for the shutdown time, and at least within the shutdown time, set the PF Flags1 () [vshut] bit. For more details, see BQ3050 Technology Reference Manual (SLU485).

Fuel metering is derivative from the compensation discharge end voltage (CEDV) methodIn this way, this method uses a mathematical model to associate the remaining charge state (RSOC) and the voltage close to the end of the discharge. For single -point FCC update, this requires a complete discharge cycle. This implementation has a function that models the battery voltage (OCV) into a function of the battery SOC, temperature and current. Impedance is also a function of SOC and temperature. It can be satisfied by using seven parameters: EMF, C0, R0, T0, R1, TC, and C1.

Function box diagram

Feature description

Main (1) security characteristics

BQ3050 supports multiple batteries and batteries and support The system protection function can be easily configured. The main safety characteristics include:

battery overvoltage/owe pressure protection

charging and discharge over current

short circuit

High charging and discharge temperature

AFE watch the door dog

Secondary (level) security characteristics

Safety characteristics can be used to indicate more serious faults through fuse. This pin can be used for melting inline fuses to permanently prohibit the battery pack from charging or discharge. The secondary safety protection function includes:

Safe overvoltage

overcharge and discharge secure current

Charging field effect transistor, discharge field effect transistor and pre -charging field effect transistor failure

battery imbalance test

Secondary voltage protection IC melting device

AFE register Integration failure (AFE_P)

AFE communication failure (AFE_C)

Charging control characteristics

BQ3050 charging control function includes:

support Jeita temperature range. Report the charging voltage and charging current according to the effective temperature range

process a more complex charging mode. The standard temperature range is allowed to be divided into two sub -range, and the charging current is allowed to change the charging current based on the battery voltage

use SMBUS broadcast to report the appropriate charging current and constant voltage charging site required to report the constant charger to the smart charger. The required proper charging voltage

During the charging process, the voltage -based battery balance algorithm is used to gradually reduce the charging difference in the battery unit in the battery pack. A voltage threshold can be set to activate the battery balance. ThisTo prevent over -charging full charging and cause excessive degradation, at the same time, the available energy of the battery pack can be increased by preventing premature termination of charging.

Support pre -charging/zero voltage charging

If the temperature of the battery pack exceeds the temperature range, support charging suppression and charging pause

# 8226; Report the charging failure, and indicate the charging and discharge alarm instructions

Gas metering

BQ3050 using the CEDV algorithm to measure and calculate the available capacity in the battery unit. BQ3050 accumulates the measurement value of charging and discharge current, and compensates the measurement value of the battery temperature and charging state. The BQ3050 estimates the self -discharge of the battery and adjust the self -discharge estimation value based on the temperature. See the BQ3050 Technical Reference Manual (SLU485).

Life data records

BQ3050 provides limited life data records for the following key battery parameters:

life expectancy the highest temperature

#8226; life minimum temperature

maximum battery voltage

minimum battery voltage

Certification

bq3050 Support the host using SHA-1 for authentication.

Qifeng and completely enter the SHA-1 certification that requires the gas meter.

Equipment function mode

BQ3050 supports three power modes to reduce power consumption:

under normal mode, the BQ3050 performs measurement and calculation every 0.25 seconds. , Protecting decision -making and data update. During these intervals, the BQ3050 is in the stage of power reduction.

In the dormant mode, the BQ3050 performs measurement, calculation, protection decision -making and data update in the adjustable time interval. During these intervals, the BQ3050 is in the stage of power reduction. The BQ3050 has a wake -up function. When the current or failure is detected, the dormant mode can be exited.

In the shutdown mode, the BQ3050 is completely disabled.

Configuration

oscillator function

BQ3050 fully integrates the system oscillator and does not require any external components to support this function.

The current operation of the system

BQ3050 regularly (1S) check the Pres pin. If the external system is pulled in the PRES to ground, the BQ3050 will detect the system.

2, 3 or 4 unit configuration

in the 2In the meta configuration, VC1 is short -circuited to VC2 and VC3. In the 3 unit configuration, VC1 is short -circuited to VC2.

Battery balance

The device supports battery balance by bypassing the current of each battery during charging or standing. If you use the internal bypass of the device, you can bypass 10 mAh, and at the same time you can bypass multiple batteries. Use external battery balance circuit to obtain higher battery balance current. In the external unit balance mode, only one unit can be balanced at a time.

The unit balance algorithm determines the amount of charge that needs to be bypassed to balance the capacity of all units.

Internal unit balance

When configuring an internal battery balance, the battery balance current is defined by the external resistor RVC of the VCX input end. See Figure 4.

External battery balance

When configuring an external battery balance, the battery balance current is defined by RB. See Figure 5. Only one battery can be balanced at a time.

Battery parameter measurement

Charging and discharge meter

BQ3050 uses integrated △ SIGMA mode converter (ADC), and Use the second Delta-Sigma ADC to measure the voltage and temperature of a single battery and battery.

Points Δ-Stegma ADC measures the charging and discharge volume of the battery by measuring the voltage between the small value sensing resistance between SR1 and SR2 pins. Points ADC measurement from -0.25 V to 0.25 V bilateral signal. When VSR V (SRP) -v (SRN) is positive, the BQ3050 detects charge activity. When VSR V (SRP) -v (SRN) is negatively detected and discharged. The BQ3050 uses an internal counter to continue integrated signals over time. The basic rate of counter is 0.65NVH.

Voltage

BQ3050 updates a single series battery voltage every 0.25 seconds. The internal ADC measurement voltage of the BQ3050 is appropriately zoomed out and calibrated. The data is also used to calculate the battery impedance of CEDV gas measurement.

current

BQ3050 uses SRP and SRN input to measure and calculate the battery charging and discharge current, the typical value is 5-mΩ to 20-mΩ. Sensor.

Automatic calibration

BQ3050 provides an automatic calibration function to eliminate the voltage offset error between SRN and SRP to obtain the maximum charge measurement accuracy. When the SMBUS line continues to be at least 5 seconds, the BQ3050 executes automatic calibration.

Temperature

BQ3050 has one internal temperature sensor and two external temperature sensorsinput of. All three temperature sensor options are enabled and configured alone for battery or FET temperature. Two configurable thermal resistance models are provided to monitor battery temperature and field effect tube temperature (probably a higher temperature type).

Communication

BQ3050 uses SMBUS V1.1 with the main mode and data packet option (PEC) options according to the SBS specification.

SMBUS opens and close status

When SMBC and SMBD are as low as two seconds or more seconds, the BQ3050 detects the SMBUS shutdown state. Clear this state requires SMBC or SMBD to be converted to high. The communication bus will restore the activity within 1 millisecond.

SBS command

Application and implementation

Note

The information in the following application chapters is not part of the TI component specification, TI does not guarantee its accuracy or its accuracy or its accuracy or Pottery. TI's customers are responsible for determining the applicability of the component. Customers should verify and test their design implementation to confirm the system function.

Application information

BQ3050 gas table is a major protection device that can be used with the 2 series, 3 series or 4 series lithium ion/lithium polymer battery packs. In order to achieve and design a set of comprehensive parameters for specific battery packs, users need BQEVSW tools, which is a graphical user interface tool installed on the PC during the development process. The firmware installed in the product has the default value. The BQ3050 Technical Reference Manual (SLU485) summarizes it. Using the BQEVSW tool, once the system parameters are known, these default values can be changed to meet specific application requirements during development, such as protective Faulttrigger thresholds, enable or disable certain operating characteristics, unit configuration, etc.

Typical application

In typical applications, BQ3050 usually paired with the second -level overvoltage protection device to provide independent voltage protection levels.

BQ3050 is usually used to provide visual display using LED display functions, but this is optional.

Design requirements

For BQ3050 design examples, the parameters in Table 1 are used as the input parameter.

Detailed design program

Large current path

High -current path starts with the battery pack+terminal of the battery pack. When the charging current passes through the battery pack, it will return to the battery pack terminal by protecting FET, chemical fuse, lithium -ion battery and battery connection, and sensing resistance. In addition, some components are placed on the battery pack+and battery pack-terminal to reduce the shadow of static dischargering.

Protect FET

For a given application, you must choose the N -channel charging and discharge field effect crystal (Figure 8). Most portable battery applications are suitable for CSD17308Q3. Ti CSD17308Q3 is a 47A-A and 30-V device. When the gate driver voltage is 10V, the RDS (ON) is 8.2MΩ.

If the pre -charged field effect transistor is used, calculate R15 to limit the pre -charged current to the required rate. Be sure to consider the power consumption of the string resistor. The pre -charged current limit is (VCHARGER – Vbat)/R15, and the maximum power consumption is 2/R15.

All the gate that protects the FET is pulled to the source pole, and there is a high resistance resistor between the gate and the source pole to ensure that they are closed when the grid driver is opened.

Capacitor C16 and C17 help to protect FET in the ESD event. If one of them is short -circuit, two devices can be used to ensure normal operation. In order to obtain good electrostatic discharge protection, the copper traces of the capacitor lead must be designed as short and wide as possible. Make sure that the rated voltage of C16 and C17 is enough to prevent the applied voltage when the capacitor is short -circuit.

Chemical fuse

Chemical fuse (Sony Chemical, Uchihashi, etc.) ignition the command of IC or gas meter fuse to protect the IC or gas meter fuse. Any event will apply a positive voltage to the gate of Q1, as shown in Figure 9, and then it absorbs the current from the third terminal of the fuse, causing the fuse to ignite and disconnect permanently.

It is important to carefully check the fuse specifications and match the required ignition current with the current provided by the N -channel FET. Make sure that the device uses the correct voltage, current and RDS (on) rated values. In the fuse circuit, the fuse control circuit was discussed in detail.

Lithium -ion battery connection

The important point of the battery connection is that the high current flows over the top and the bottom connection; therefore The induction lead must be connected to Kelvin to avoid any errors caused by the decline in high -current copper traces. The position of 4P in FIG. 10 represents the Kailvin connection of the most positive battery node. The connection marked as 1N is equally important. The VC5 pins in the old generation (the grounding benchmark of the battery voltage measurement) is not in the BQ3050 device. Therefore, one -point connection is needed at 1N to connect to a small current to avoid accidental voltage drops through a long trajectory when the battery voltage at the bottom of the gas pressure meter is measured.

Sensor

Like the battery connection, the sensing resistanceThe quality of the Kailvin connection is crucial. The temperature coefficient of sensor resistance must not be greater than 75 PPM to minimize the current measurement as the temperature changes (Figure 11). Choose sensing resistance values corresponding to the BQ3050 with a current and short -circuit range. Choose a possible minimum value to minimize the negative voltage generated on the BQ3050 VSS node during the short circuit. The absolute minimum value of this pin is -0.3 V. For a battery pack with two parallel cylindrical batteries, 10 MΩ is usually ideal. As long as the good Kelvin sensor is guaranteed, the parallel resistor can be used.

The ground plan of the BQ3050 is different from the old generation of equipment. In the previous device, the equipment ground (or low -current grounding) is connected to the SRN side of the RSENSE resistance pad. However, the BQ3050 connects low -current grounding on the SRP side of the RSENSE resistance pad, close to the battery 1N terminal (see lithium -ion battery connection). This is because compared with the previous device, the BQ3050 has one less VC pin (a ground reference pin VC5). After selling and combining it into SRP.

ESD relief

One-to-0.1-μF series ceramic capacitors are placed on the battery pack+and battery pack-terminal to help reduce external static discharge. If one of the capacitors is short -circuited, two series of devices can ensure the continuous operation of the battery pack.

Optional land, you can place a Transzorb between the terminals, such as SMBJ2A to further increase the ESD antipness.

Gas meter circuit

The gas meter circuit includes BQ3050 and its peripheral components. These components are divided into the following groups: differential low -pass filters, power supply decoupling/RBI, system presence, SMBUS communication, fuse circuit and LED.

Differential low -pass filter

As shown in Figure 12, the differential filter must be input at the current of the gas meter. The filter eliminates the impact of unnecessary digital noise, and these noise will cause the offset of the measurement current. Even the best differential amplifier has less co -mode suppression under high frequency. In the case of no filter, the amplifier input level can correct the RF signal, and then the signal may have a DC offset error.

Because the capacitor C15 diverts C12/C13 and reduces the communication co -mode due to the loss of components, the 5%tolerance of the component is sufficient. It also proves that it can reduce the offset and noise errors by maintaining the μA symmetrical placing pattern and adding ground shielding to the differential filter network.

Power decoupling and RBI

Power decoupling is an important link for the optimization operation of the advanced gas meter BQ3050. As shown in the middle, a single 1.0-μ from REG33 to VSS and REG25 to VSSF ceramic decoupling container must be placed near the IC pin.

The RBI pin is used to provide spare RAM voltage during a short -lived instantaneous power off. Some reset mechanisms use RAM to restore key CPU registers after temporary power off. The standard 0.1-μF ceramic capacitor is grounded from the RBI pin, as shown in Figure 13.

System existence

The system existing signal is used to notify whether the gas meter component is installed in the system or removed from the system. In the host system, this pin is grounded. Occasionally sample the PRES pin of the BQ3050 to test whether there is a system. In order to save electricity, the gas meter provides an internal pull -up resistor during a short -term sample pulse of 4μs per second.

Since the current signal of the system is part of the component connector and the external interface, it must be protected to prevent it from being affected by the external electrostatic discharge event. The integrated ESD protection on the PRES device pin reduces the external protection requirements of the 8-KV ESD contact rate to R25 (Figure 14). However, if the current signal of the system may be short -circuited to PACK+, it must include R18 and D3 for high -voltage protection.

SMBUS Communication

Similar to the existing pin of the system, the SMBUS clock and data pin integrated high -voltage ESD protection circuit, reducing the external Qina diode pipe The need for protection. When the circuit shown in Figure 15, the communication line can withstand 8 KV (contact) ESD shock. The choice value of C23 and C24 is 100 PF to meet the SMBUS specifications. If you need to use a larger input resistance and/or Qina diode to provide higher protection, carefully study the signal quality of the SMBUS signal under the worst case.

SMBUS clock and data cable have internal drop -down menus. When the instrument is in a low -power calibration state, both sensors enter the automatic calibration mode.

The fuse circuit

The fuse needle design of the BQ3050 is used to ignite the chemical fuse in violation of various safety standards (Figure 16). The conclusions also monitor the status of the auxiliary voltage protection IC. Q3 ignite the chemical fuse when the door is high. The 7V output of the BQ29705 is separated by R13 and R14, which provides sufficient grille drivers for Q1, and at the same time, it is used to prevent excessive reverse currents of BQ29705 with high feldling signals.

Use C14 is usually a good approach, especially for RFI's antipity. If necessary, you can remove C14 because chemical fuse is a relatively slow device and is not affected by any sub -microsecond -grade failure that may occur during the battery connection process.

When the BQ3050 is commanded to ignite the chemical fuse, the fuse is activated and provides a typical 8 -volt output. The new design makes it possible to use higher VGS field effect crystals in Q1. This improves the robustness of the system and has also expanded the scope of Q1.

PFIN detection

As mentioned earlier, the fuse needle has a dual effect on the device. When the BQ3050 is not instructed to ignite the chemical melting, the fuse pins default sensing the outkop pins of the secondary voltage protector. When the secondary voltage protector ignitions the chemical fuse, the high voltage is induced by the fuse pins, and the BQ3050 is set to the PFIN logo accordingly.

Secondary current protection

BQ3050 provides secondary over current and short -circuit protection, unit balance, unit voltage reuse and voltage conversion. The following chapters check the battery and battery input, battery pack and field effect control control, regulator output, temperature output and battery balance.

Battery and battery input

Each battery input has a simple RC filter that provides ESD protection during the battery connection and is used to filter the unwanted voltage transient. The resistance value allows some balance between battery balance and safety protection.

The internal battery balance in BQ3050 usually provides about 310Ω (310Ω, battery voltage ≥2 V. Battery balancing FET is reduced to typical 125Ω in the case of battery voltage ≥4 V), which can be used to bypass a single single. The charging current in the battery (relative to other batteries overcharged) (Figure 17). The purpose of this bypass is to reduce the current that enters any battery during the charging, so that the series components can reach the same voltage. Stand -up resistance control by the input pin and positive series component nodes. The BQ3050 device design is used to absorb a battery balance current of 10 mA. It is recommended to use the series input resistance between 100Ω and 1 kΩ to achieve effective balance of the battery.

BAT input uses diode (D1) and 1-μF ceramic capacitors (C9) to isolate it from the battery, and separates it from the battery when the short-circuit event causes the voltage to fall.

In addition, as mentioned in the high -current path, the top and bottom nodes of the battery must be induced at the battery connection through the Kelvin connection to prevent the voltage sensor errors caused by the decline in high -current PCB copper lines.

External battery balance

Internal battery balance can only support 10 mA. External unit balance provides another choice for faster unit balance. For details, please refer to the application instructions and use the external MOSFET (SLUA420) for fast unit balance.

Packaging and field effect transistor control

Battery pack and VCC input power from the charger to BQ305X.The battery pack also provides a way to measure and detect the existence of the charger. The block input uses a 10-kΩ resistor, while the VCC input uses diode to prevent input from entering the transient and prevent data drives from failing in short-circuit events (Figure 18).

N -channel charging and discharge FET is controlled by the 5.1kΩ series grid resistance, and the switching time constant is a few micro seconds. 3.01 MΩ resistor ensure that the FET is closed when the FET driver is disconnected. Q4 is used to protect discharge FET (Q3) in the case of reverse connection charger. If there is no Q4, Q3 may be driven to its linear area, and if the Pack+input becomes negative, it will suffer serious damage.

In this case, Q4 opens and protects Q3 through short -circuited door to source. In order to use a simple ground grid circuit, FET must have a lower grille opening threshold. If you need to use more standard devices, such as 2n7000 as the reference schematic, the grid bias to 3.3V should be used to use a high -value resistor. The BQ3050 device can provide a limited -limited charging path, which is usually used for low battery voltage or low -temperature charging. The pre -charged FET is integrated in the BQ3050 device, allowing users to input the external pre -charged load resistor through the PCR tube foot through PCHGIN input. The BQ3050 device supports a pre -charging current of up to 100 mAh. When choosing an external load resistor, the RDSON that should be considered the maximum charging voltage and the internal pre -charging field effect tube should be considered.

The regulator output

As described in the power supply and RBI, the two low -voltage differential regulators in the BQ3050 need to compensate the output capacitor. The output must have a 1-μF ceramic capacitor and placed near the IC terminal pins.

Temperature output

For the BQ3050 device, TS1 and TS2 provide armistor driving under program control (Figure 19). Each pin can be used to line up linearly with a linear pilot of the integrated 18-kΩ (typical) to support the use of 10-kΩntc external thermistor, such as Mitsubishi BN35-3H103 at 25 ° C (103). The reference design includes two 10-kΩ thermistor: RT1 and RT2.

Lighting diode

LED does not require a current -limiting resistor, because the BQ3050 LED pin has a programmable current receiver, which is simplified design (Figure 20 To. The display switch pulls the BQ3050 pin 20 to the ground to interrupt. REG33 outputs LED power.

Security PTC thermistor

BQ3050 device supports security PTC thermistor (Figure 21). PTC thermistor is connected between the PTC pin and the speed sensor. It can be placedMonitor the temperature at a place near CHG/DSG FET. The PTC pin output is very small, the typical value is about 370 mAh, and the PTC failure will be triggered at about 0.7 volts. PTC failure is a permanent fault mode. It can only be removed by POR.

To disable this function, please connect a 10-kΩ resistor between PTC and VSS.

Second overvoltage protection

BQ29705 provides secondary overvoltage protection and ordered chemical fuse to ignite when any battery exceeds the internal reference threshold. The perip