TL3845B description
The TL284xB and TL384xB series control ICs provide the necessary features to enable off-line or dc-to-dc frequency point current-based control solutions with minimal external components.The internal implementation circuitry includes a branch on-the-road low-voltage lockout (UVLO) and a sophisticated reference book clipping error amplifier for accuracy input.Other internal circuitry includes logic operation, ensuring a one-pulse wide modulation (PWM) comparator, which also provides current-limit control, and a totem-pole output stage or pump design high-peak source current.The output stage is suitable for driving N-channel mosfets, and when it is low, it is in the off state.
The TL284xB and TL384xB series have the following improvements for the standard TL284x pin fit and TL384x.The starting current is specified at 0.5 masters (highest), while the oscillator discharge current is trimmed to 8.3% masters (current).In addition, under dynamic conditions, the low voltage lock on the output branch has a maximum of 1.2 V while the saturation sinks by 10 ms (VCC = 5 volts).
The main differences between the members, this series is the range of UVLO thresholds and maximum processes.Typical UVLO thresholds of 16 V (up) and 10 V (off) in the TLx842B and TLx844B units make them ideal for off-line applications.The corresponding typical thresholds are 8.4 V (on) and 7.6 V (off) for the TLx843B and TLx845B units.The TLx842B and TLx843B units are operational with a duty cycle of nearly 100%.A process ranges from 0 to 50%, and the TLx844B is obtained by adding an internal toggle trigger output to keep all other blank clock cycles.Features of TL284xB-series units - Operates at 40°C from to 85°C.The TL384xB-series devices are characterized by the ability to operate from 0°C to 70°C.