Overview
The MC33342, produced by onsemi, is a monolithic control IC specifically designed as a fast charge controller for Nickel Cadmium (NiCd) and Nickel Metal Hydride (NiMH) batteries. This device features advanced protective and control mechanisms to ensure safe and efficient battery charging. The MC33342 is part of the MC33340/342 series, differing primarily in its fast charge holdoff time, which is 708 seconds for the MC33342.
Key Specifications
| Characteristic | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Power Supply Voltage (Pin 8) | VCC | 18 | V | ||
| Input Voltage Range | V | −1.0 | VCC | V | |
| Battery Sense Input Voltage | VIR(sen) | −1.0 | VCC + 0.6 or 10 | V | |
| Vsen Gate Output Voltage | VO(gate) | 20 | V | ||
| Vsen Gate Output Current | IO(gate) | 50 | mA | ||
| Fast/Trickle Output Voltage | VO(F/T) | 20 | V | ||
| Fast/Trickle Output Current | IO(F/T) | 50 | mA | ||
| Thermal Resistance, Junction−to−Air | RθJA | 100 (P Suffix), 178 (D Suffix) | °C/W | ||
| Operating Junction Temperature | TJ | +150 | °C | ||
| Operating Ambient Temperature | TA | −25 | +85 | °C | |
| Storage Temperature | Tstg | −55 | +150 | °C | |
| Fast Charge Holdoff Time | thold | 708 | seconds |
Key Features
- Negative Slope Voltage Detection with 4.0 mV Sensitivity
- Accurate Zero Current Battery Voltage Sensing
- High Noise Immunity with Synchronous VFC/Logic
- Programmable 1 to 4 Hour Fast Charge Time Limit
- Programmable Over/Under Temperature Detection
- Battery Over and Undervoltage Fast Charge Protection
- Power Supply Input Undervoltage Lockout with Hysteresis
- Operating Voltage Range of 3.25 V to 18 V
- Pb−Free Packages are Available
Applications
The MC33342 is designed for use in various battery charging applications, particularly for Nickel Cadmium (NiCd) and Nickel Metal Hydride (NiMH) batteries. It is suitable for use in:
- Battery chargers for portable electronics
- Industrial battery charging systems
- Automotive battery charging applications
- Line isolated linear regulator chargers
Q & A
- What is the primary function of the MC33342?
The MC33342 is a fast charge controller designed for Nickel Cadmium (NiCd) and Nickel Metal Hydride (NiMH) batteries.
- What is the fast charge holdoff time for the MC33342?
The fast charge holdoff time for the MC33342 is typically 708 seconds.
- What protective features does the MC33342 include?
The MC33342 includes battery over and undervoltage detection, latched over temperature detection, and power supply input undervoltage lockout with hysteresis.
- How does the MC33342 detect fast charge termination?
The MC33342 uses negative slope voltage detection as the primary means for fast charge termination, with an additional secondary backup termination method that can be either a programmable time or temperature limit.
- What is the operating voltage range of the MC33342?
The operating voltage range of the MC33342 is from 3.25 V to 18 V.
- Is the MC33342 available in Pb−Free packages?
- How does the temperature sensing work in the MC33342?
Temperature sensing is accomplished by placing a negative temperature coefficient (NTC) thermistor in thermal contact with the battery pack, connected to the t2/Tsen input.
- What is the significance of the Vsen input voltage range?
The Vsen input voltage range between 1.0 V and 2.0 V indicates that the battery pack voltage is within the fast charge range. Voltages outside this range switch the charger to trickle mode.
- How does the negative slope voltage detector work?
The negative slope voltage detector senses a negative drop in battery voltage after an initial holdoff period, switching the charger to trickle mode if the condition persists.
- What are the typical applications of the MC33342?
The MC33342 is typically used in battery chargers for portable electronics, industrial battery charging systems, automotive battery charging applications, and line isolated linear regulator chargers.
