text.skipToContent text.skipToNavigation

Manufacturer Part #

UC3844BD1R2G

UC3844B Series 17 mA 275 kHz High Performance Current Mode Controller - SOIC-8

ECAD Model:
Mfr. Name: onsemi
Standard Pkg:
Product Variant Information section
Date Code: 2210
Product Specification Section
onsemi UC3844BD1R2G - Technical Attributes
Attributes Table
Supply Current-Max: 17mA
Supply Voltage: 10V to 30V
Frequency-Max: 275kHz
Topology: Flyback
Rated Power: 702mW
Duty Cycle-Min: 0%
Duty Cycle-Max: 50%
Operating Temp Range: 0°C to 70°C
Storage Temperature Range: -65°C to +150°C
Output Current: -1mA
Thermal Resistance: 178°C/W
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:
2,500
USA:
2,500
5,000
Factory Stock:Factory Stock:
0
Factory Lead Time:
35 Weeks
Minimum Order:
2500
Multiple Of:
2500
tariff icon
Tariff charges may apply if shipping to the United States. An estimate of tariff charges will be calculated at checkout.
Total
$637.50
USD
Quantity
Web Price
2,500
$0.255
5,000
$0.25
7,500
$0.245
10,000+
$0.24
Product Variant Information section