Overview
The BQ2057TTS, part of the BQ2057 series from Texas Instruments, is an advanced linear charge-management IC designed for lithium-ion (Li-ion) and lithium-polymer (Li-pol) battery packs. This IC is ideal for cost-sensitive and compact portable electronics, offering high-accuracy current and voltage regulation, battery conditioning, temperature monitoring, charge termination, and charge-status indication. It is available in various package options, including MSOP, TSSOP, and SOIC, to fit a wide range of applications.
Key Specifications
| Parameter | Description | Min | Max | Unit | |
|---|---|---|---|---|---|
| Supply Voltage (VCC with respect to GND) | -0.3 | 18 | V | ||
| Input Voltage (SNS, BAT, TS, COMP with respect to GND) | -0.3 | VCC+0.3 | V | ||
| Output Voltage Regulation (VO(REG)) | BQ2057T | 8.119 | 8.20 | 8.282 | V |
| Current Regulation Threshold (V(SNS)) | High-side current sensing configuration | 103.6 | 125 | 137.5 | mV |
| Charge Termination Current Detect Threshold (I(TERM)) | -30 | -14 | -4 | mV | |
| Lower Temperature Threshold (V(TS1)) | 29.1 | 30 | 30.9 | %VCC | |
| Upper Temperature Threshold (V(TS2)) | 58.3 | 60 | 61.8 | %VCC | |
| Precharge Threshold (V(min)) | BQ2057T | 5.9 | 6.1 | 6.22 | V |
| Precharge Current Regulation (I(PRECHG)) | 3 | 13 | 22 | mV | |
| Recharge Threshold (V(RCH)) | BQ2057T | VO(REG)-196 | VO(REG)-200 | VO(REG)-204 | mV |
Key Features
- Ideal for single (4.1 V or 4.2 V) and dual-cell (8.2 V or 8.4 V) Li-ion or Li-pol packs.
- Requires a small number of external components.
- High-accuracy current and voltage regulation.
- Battery conditioning, temperature monitoring, charge termination, and charge-status indication.
- AutoComp™ charge-rate compensation to reduce charging time.
- Continuous battery temperature monitoring using an external thermistor.
- Charge inhibition if the battery temperature is outside user-defined thresholds.
- Three-phase charging: conditioning, constant current, and constant voltage.
- Charge-status output with three-state indication (charge in progress, charge complete, and temperature fault or sleep mode).
- Charge-control output to drive an external pass-transistor (PNP or P-channel MOSFET) for current and voltage regulation.
Applications
- Telematics control units.
- Aftermarket telematics.
- Gaming and computer accessories.
- Portable medical equipment.
- EPOS card readers.
Q & A
- What is the BQ2057TTS used for?
The BQ2057TTS is used for managing the charging of lithium-ion (Li-ion) and lithium-polymer (Li-pol) battery packs in various portable electronic devices.
- What are the different package options available for the BQ2057 series?
The BQ2057 series is available in MSOP, TSSOP, and SOIC package options.
- How does the BQ2057TTS regulate battery temperature?
The BQ2057TTS continuously monitors battery temperature using an external thermistor and inhibits charge if the temperature is outside user-defined thresholds.
- What are the three phases of charging in the BQ2057TTS?
The three phases are conditioning, constant current, and constant voltage.
- How does the AutoComp feature work?
The AutoComp feature allows for dynamic compensation of the internal impedance of the battery pack during charge, reducing charging time safely.
- What is the purpose of the charge-status output?
The charge-status output provides a three-state indication of charge in progress, charge complete, and temperature fault or sleep mode.
- How does the BQ2057TTS handle precharging?
If the battery voltage is below the precharge threshold, the BQ2057TTS uses a low current to condition the battery, minimizing heat dissipation in the external pass-element.
- What triggers the charge termination in the BQ2057TTS?
Charge termination occurs when the charging current tapers off to the charge termination threshold, I(TERM).
- Can the BQ2057TTS be used for both single and dual-cell battery packs?
Yes, the BQ2057TTS is offered in versions suitable for both single (4.1 V or 4.2 V) and dual-cell (8.2 V or 8.4 V) Li-ion or Li-pol packs.
- How does the BQ2057TTS restart the charge cycle?
A new charge cycle begins when the battery voltage falls below the V(RCH) threshold.
