Summary of LTC4040 – 2.5A Battery Backup Power Manager
The LTC4040 is a compact battery backup system offering 2.5A boost from single-cell Li-Ion or LiFePO4 batteries. It features seamless switching, adjustable input current limiting, and programmable charge voltages. The device includes an optional overvoltage protection circuit and operates at constant frequency within a low-profile QFN package, making it ideal for automotive and security applications.
Parts used in the LTC4040 Battery Backup System:
- Step-Up DC/DC Regulator
- Step-Down Battery Charger
- 6.5A Switches
- Input Disconnect Switch
- Input Power Loss Indicator
- System Power Loss Indicator
- Optional OVP Circuitry
- Pin Selectable Battery Logic Inputs
- 24-Lead 4mm × 5mm QFN Package
Features
- Step-Up Backup Supply and Step-Down Battery Charger
- 6.5A Switches for 2.5A Backup from 3.2V Battery
- Input Current Limit Prioritizes Load Over Charge Current
- Input Disconnect Switch Isolates Input During Backup
- Automatic Seamless Switch-Over to Backup Mode
- Input Power Loss Indicator
- System Power Loss Indicator
- Pin Selectable Battery: Li-Ion (3.95V/4.0V/4.05V/4.1V) or LiFePO4 (3.45V/3.5V/3.55V/3.6V)
- Optional OVP Circuitry Protects Device to >60V
- Constant Frequency Operation
- Low Profile (0.75mm) 24-Lead 4mm × 5mm QFN Package
Description
The LTC®4040 is a complete 3.5V to 5.5V supply rail battery backup system. It contains a high current step-up DC/DC regulator to back up the supply from a single-cell Li-Ion or LiFePO4 battery. When external power is available, the step-up regulator operates in reverse as a step-down battery charger.
The LTC4040’s adjustable input current limit function reduces charge current to protect the main supply from overload while an external disconnect switch isolates the external supply during backup. When the input supply drops below the adjustable PFI threshold, the 2.5A boost regulator delivers power from the battery to the system output.
An optional input overvoltage protection (OVP) circuit protects the LTC4040 from high voltage damage at the VIN pin. One logic input selects either the Li-Ion or the LiFePO4 battery option, and two other logic inputs program the battery charge voltage to one of four levels suitable for backup applications. The LTC4040 is available in a low profile (0.75mm) 24-Lead 4mm × 5mm QFN package.
Applications
- Fleet and Asset Tracking
- Automotive GPS Data Loggers
- Automotive Telematics Systems
- Toll Collection Systems
- Security Systems
- USB Powered Devices
For More Details: LTC4040 – 2.5A Battery Backup Power Manager
- How does the LTC4040 handle power loss?
The system automatically switches seamlessly to backup mode when the input supply drops below the adjustable PFI threshold. - Can the LTC4040 charge different battery types?
Yes, one logic input selects either Li-Ion or LiFePO4 battery options. - What is the maximum backup current provided?
The 2.5A boost regulator delivers power from the battery to the system output during backup. - Does the device offer overvoltage protection?
An optional input overvoltage protection circuit protects the device from high voltage damage at the VIN pin. - How many charge voltage levels are available?
Two logic inputs program the battery charge voltage to one of four suitable levels. - What is the package size of the LTC4040?
It is available in a low profile 0.75mm 24-Lead 4mm × 5mm QFN package. - Does the input current limit prioritize load or charge?
The function prioritizes load over charge current to protect the main supply from overload. - What applications utilize this power manager?
Applications include fleet tracking, automotive GPS loggers, telematics systems, toll collection, security systems, and USB powered devices.
