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Manufacturer Part #

UC3845BD1G

UC3845B Series 36 V 275 kHz High Performance Current Mode Controller - SOIC-8

Product Specification Section
onsemi UC3845BD1G - Technical Attributes
Attributes Table
Supply Current-Max: 17mA
Supply Voltage: 7.6V to 36V
Turn On Threshold Voltage: 16V
Turn Off Threshold Voltage: 10V
Duty Cycle-Max: 50%
Frequency-Max: 275kHz
Operating Temp Range: 0°C to 70°C
Package Style:  SOIC-8
Mounting Method: Surface Mount
Features & Applications

The UC3844B, UC3845B series are high performance fixed frequency current mode controllers. They are specifically designed for Off−Line and dc−dc converter applications offering the designer a cost−effective solution with minimal external components. These integrated circuits feature an oscillator, a temperature compensated reference, high gain error amplifier, current sensing comparator, and a high current totem pole output ideally suited for driving a power MOSFET.

Also included are protective features consisting of input and reference undervoltage lockouts each with hysteresis, cycle−by−cycle current limiting, a latch for single pulse metering, and a flip−flop which blanks the output off every other oscillator cycle, allowing output deadtimes to be programmed from 50% to 70%. These devices are available in an 8−pin dual−in−line and surface mount (SOIC−8) plastic package as well as the 14−pin plastic surface mount (SOIC−14). The SOIC−14 package has separate power and ground pins for the totem pole output stage. The UCX844B has UVLO thresholds of 16 V (on) and 10 V (off), ideally suited for off−line converters. The UCX845B is tailored for lower voltage applications having UVLO thresholds of 8.5 V (on) and 7.6 V (off).

Key Features:

  • Trimmed Oscillator for Precise Frequency Control
  • Oscillator Frequency Guaranteed at 250 kHz
  • Current Mode Operation to 500 kHz Output Switching Frequency
  • Output Deadtime Adjustable from 50% to 70%
  • Automatic Feed Forward Compensation
  • Latching PWM for Cycle−By−Cycle Current Limiting
  • Internally Trimmed Reference with Undervoltage Lockout
  • High Current Totem Pole Output
  • Undervoltage Lockout with Hysteresis
  • Low Startup and Operating Current
  • Pb−Free Packages are Available
Pricing Section
Global Stock:
3,326
Germany (Online Only):
3,326
3,430
Factory Stock:Factory Stock:
0
Factory Lead Time:
35 Weeks
Minimum Order:
98
Multiple Of:
98
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Total
$28.42
USD
Quantity
Web Price
98
$0.29
392
$0.28
1,960
$0.265
3,920
$0.26
12,250+
$0.25