UC3862DW

UC3862 and UC3863 are low cost, high performance, current mode, pulse width modulation (PWM) ICs that are the main parts of AC-DC or DC-DC converter applications, off-line switcher applications and related businesses. The UC3862DW is one of the more popular members of the UC3862 family and operates in the same way.

The UC3862DW provides circuits with various features to work: tight voltage regulation range, low harmonic distortion, low jitter operating frequency, soft start, protection against over-voltage, protection against over-current, as well as minimum external components. The potential applications of this device are extensive, covering AC and DC to AC, DC to DC or DC to AC applications and can easily meet the needs of medium to high end off-line switchers, such as computer systems, power supplies, motor control and home appliances.

The UC3862DW is based on the linear current-mode control principle, which is generally preferred when designing off-line switchers because it offers better switching characteristics than traditional pulse frequency modulation (PFM) or conventional pulse density modulation (PDM) or other nonlinear techniques. In comparison to other current-mode control ICs, the UC3862DW also has faster transient response and improved smoothness of voltage across multiple ripple.

The UC3862DW is designed to maintain a constant, stable output voltage and frequency in response to changes in input voltage and load current. The UC3862DW senses the current flowing through the switching transistor and adjusts its duty cycle accordingly to regulate the output voltage. This device operates from an input voltage range of 4 to 35V and can maintain its output voltage regulation even if a large change of the input voltage occurs. Its maximum output current is 1.5A and the switching frequency can be tuned from 30 to 300 kHz by an external resistor.

The UC3862DW also features several safety features to protect against potential damages or malfunctions. Its low-ripple over-voltage protection keeps the output voltage within a pre-determined limit. Additionally, an over-current protection circuit is included to protect against over-currents generated by an overloaded system or an over-dense output capacitor. In addition, the device includes both a soft-start and a thermal-shutdown feature.

The UC3862DW is a well built, feature packed and cost effective integrated device meant for use in off-line switching applications. Its current mode control architecture allows for greater stability and smoother operation for applications requiring variable output voltage, frequency or load current. With its safety mechanisms, it also minimizes the possibility of equipment damage and provides users with much needed peace of mind.