Overview
The BQ25171-Q1, produced by Texas Instruments, is an automotive-rated, standalone 800-mA linear battery charger designed for a variety of battery types including 1- to 2-cell Li-ion, Li-polymer, LiFePO4, and 1- to 6-cell NiMH. This device is AEC-Q100 qualified, ensuring its suitability for harsh automotive environments with a temperature range of –40°C to 125°C. It features a single power output that can charge the battery while allowing system loads to be placed in parallel, provided the system load does not prevent the battery from charging fully within the safety timer duration.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Voltage IN | –0.3 | 40 | V | |
| Voltage OUT | –0.3 | 13 | V | |
| Voltage CE, CHM_TMR, ISET, STAT1, STAT2, TS, VSET | –0.3 | 5.5 | V | |
| Junction Temperature (TJ) | –40 | 150 | °C | |
| Storage Temperature (Tstg) | –65 | 150 | °C | |
| Charge Current Regulation Range | 10 | 800 | mA | |
| Charge Current Accuracy | ±10% | |||
| Output Sink Current (STAT1, STAT2) | 5 | mA | ||
| Thermal Shutdown Temperature | 150 | °C |
Key Features
- AEC-Q100 qualified for automotive applications with a temperature grade 1: –40°C ≤ TA ≤ 125°C.
- ±0.5% charge voltage accuracy and ±10% charge current accuracy.
- Charging features include precharge current (20% of ISET), termination current (10% of ISET), and NTC thermistor input to monitor battery temperature.
- CE pin for charging function control and two open-drain outputs for status and fault indication.
- Integrated fault protection including 18-V IN overvoltage protection, VSET based OUT overvoltage protection, 1000-mA overcurrent protection, and thermal regulation with 125°C thermal shutdown protection.
- OUT short-circuit protection and VSET, ISET, CHM_TMR pins short/open protection.
Applications
- Telematics control unit (TCU)
- Emergency call (eCall)
- Fleet management and asset tracking
- Remote keyless entry (RKE) keyfob
Q & A
- What types of batteries does the BQ25171-Q1 support?
The BQ25171-Q1 supports 1- to 2-cell Li-ion, Li-polymer, LiFePO4, and 1- to 6-cell NiMH batteries.
- What is the charge current range of the BQ25171-Q1?
The charge current range is from 10 mA to 800 mA.
- What is the temperature range for the BQ25171-Q1?
The device operates within a temperature range of –40°C to 125°C.
- What kind of fault protections does the BQ25171-Q1 have?
The device includes overvoltage protection, overcurrent protection, thermal regulation, and short-circuit protection among others.
- Can system loads be connected in parallel with the battery?
- How does the BQ25171-Q1 charge Li-ion and NiMH batteries?
The device charges Li-ion batteries in three phases: precharge, fast-charge constant current, and voltage regulation. For NiMH batteries, it charges in constant current mode only and terminates the charge cycle based on a programmable timer or when the battery voltage exceeds the VOUT_OVP threshold.
- What is the purpose of the CE pin on the BQ25171-Q1?
The CE pin is used for charging function control.
- How does the BQ25171-Q1 monitor battery temperature?
The device uses an NTC thermistor input to monitor battery temperature.
- What are the typical applications of the BQ25171-Q1?
Typical applications include telematics control units, emergency call systems, fleet management, asset tracking, and remote keyless entry keyfobs.
- Is the BQ25171-Q1 suitable for automotive environments?
