Overview
The LTC4121IUD#PBF, produced by Analog Devices Inc., is a 400mA constant-current/constant-voltage (CC/CV) synchronous step-down battery charger. This device is designed to regulate its input voltage to a programmable percentage of the input open-circuit voltage, which is particularly useful for high impedance input sources such as solar panels. It offers high efficiency, accurate charge current programming, and various protection features, making it suitable for a range of applications including handheld instruments, solar-powered devices, and industrial/military sensors.
Key Specifications
| Parameter | Value | Units |
|---|---|---|
| Operating Input Supply Range | 4.4 to 40 | V |
| Battery Voltage Range (LTC4121) | 0 to 18 | V |
| Battery Voltage Range (LTC4121-4.2) | 0 to 4.2 | V |
| Charge Current Range | 50 to 400 | mA |
| Feedback Voltage Accuracy | ±1% | |
| Programmable Charge Current Accuracy | 5% | |
| Efficiency | Up to 95% | % |
| Operating Temperature Range | -40 to 125 | °C |
| Package Type | 16-Lead Plastic QFN | |
| Package Dimensions | 3mm × 3mm |
Key Features
- High efficiency up to 95%
- Programmable charge current from 50mA to 400mA with 5% accuracy
- Fixed 4.2V float voltage option (LTC4121-4.2) or programmable float voltage (LTC4121)
- Feedback voltage accuracy of ±1%
- Maximum power point tracking (MPPT) for high impedance input sources like solar panels
- Low voltage battery preconditioning and bad battery fault detection
- Timer termination and auto-recharge capabilities
- NTC temperature qualified charging
- FAULT pin indication for bad battery or temperature faults
Applications
- Handheld instruments
- Solar-powered devices
- Industrial/military sensors and devices
Q & A
- What is the primary function of the LTC4121IUD#PBF? The primary function is to act as a 400mA constant-current/constant-voltage (CC/CV) synchronous step-down battery charger.
- What is the operating input supply range of the LTC4121IUD#PBF? The operating input supply range is from 4.4V to 40V.
- What are the battery voltage ranges for the LTC4121 and LTC4121-4.2? For the LTC4121, the range is 0 to 18V, and for the LTC4121-4.2, it is 0 to 4.2V.
- How is the charge current programmed? The charge current can be programmed from 50mA to 400mA using an external resistor.
- What is the efficiency of the LTC4121IUD#PBF? The efficiency is up to 95%.
- What is the operating temperature range of the LTC4121IUD#PBF? The operating temperature range is from -40°C to 125°C.
- What package type is used for the LTC4121IUD#PBF? It is packaged in a 16-Lead Plastic QFN.
- What are some key features of the LTC4121IUD#PBF? Key features include high efficiency, programmable charge current, fixed or programmable float voltage, and maximum power point tracking (MPPT).
- What applications is the LTC4121IUD#PBF suitable for? It is suitable for handheld instruments, solar-powered devices, and industrial/military sensors and devices.
- How does the LTC4121IUD#PBF handle bad battery or temperature faults? It provides an indication of bad battery or temperature faults through the FAULT pin.
