MIC38C44

The MIC38C4x are fixed frequency, high performance, current-mode PWM controllers. Micrel's BiCMOS devices are pin compatible with 384x bipolar devices but feature several improvements. Undervoltage lockout circuitry allows the '42 and '44 versions to start up at 14.5V and operate down to 9V, and the '43 and '45 versions start at 8.4V with operation down to 7.6V. All versions operate up to 20V. When compared to bipolar 384x devices operating from a 15V supply, start-up current has been reduced to 50µA typical and operating current has been reduced to 4.0 mA typical. Decreased output rise and fall times drive larger MOSFETs, and rail-to-rail output capability increases efficiency, especially at lower supply voltages. The MIC38C4x also features a trimmed oscillator discharge current and bandgap reference. MIC38C4x denotes 8-pin plastic DIP, SOIC, and MM8® packages. MIC38C4x-1 denotes 14-pin plastic DIP and SOIC packages. 8-pin devices feature small size, while 14-pin devices separate the analog and power connections for improved performance and power dissipation. For fast rise and fall times and higher output drive, refer to the MIC38HC4x.

Features
  • Fast 40ns output rise and 30ns output fall times
  • -40°C to +85°C temperature range meets UC284x specifications
  • High-performance, low-power BiCMOS Process
  • Ultra-low start-up current (50µA typical)
  • Low operating current (4mA typical)
  • CMOS outputs with rail-to-rail swing
  • ≥500kHz current-mode operation
  • Trimmed 5V bandgap reference
  • Pin-for-pin compatible with UC3842/3843/3844/3845(A)
  • Trimmed oscillator discharge current
  • UVLO with hysteresis
  • Low cross-conduction currents
Parameter
Parameter Name Value Value
Supported Topologies Forward,Flyback Forward,Flyback
Supported Outputs 1 1
Minimum Input Voltage (V) 9 9
Maximum Input Voltage (V) 20 20
PFM, Discontinuous, Hyperlight load, or Skip Mode False False
Typical Tolerance (%) ±2 ±2
Duty Cycle Max (%) 0.5 0.5
Operating Frequency (Hz) Adj. to 500kHz Adj. to 500kHz
External Clock Sync False False
Power Good Signal False False
Soft Start False False
Internal Compensation False False
Internal Voltage Bias True True
Enable Pin False False
Current Limit / Short Circuit Protection False False
Input UVLO Typ (V) 14.5 14.5
Operating Supply Current (mA) 4 4
Package 8/PDIP, 8/SOIC, 8/MSOP 14/PDIP, 14/SOIC 8/PDIP, 8/SOIC, 8/MSOP 14/PDIP, 14/SOIC
Documents
MIC38C42/3/4/5 - BiCMOS Current-Mode PWM ControllersData Sheets11/09/2015343KB
Ordering Information
Part NumberLeadsPackage TypeTemp RangePacking1+26+100+1000+5000+
MIC38C44AYM-TR8SOIC-40C to +85CT/R1.771.471.341.121.03
MIC38C44YM8SOIC-40C to +85CTUBE**********
MIC38C44YM-TR8SOIC-40C to +85CT/R1.721.431.301.081.00
MIC38C44YN8PDIP-40C to +85CTUBE**********
RoHS Information
PartNumberDeviceWeightShippingWeightLeadCountPackageTypePackageWidthSolderCompositionJEDECIndicatorRoHSChinaEFUP
MIC38C44-1YN0.9533001.83333314PDIP.300inMatte Tine3
MIC38C44YN0.4867000.9000008PDIP.300inMatte Tine3
MIC38C44-1YM0.1432000.28070214SOIC.150In(3.90mm)Matte Tine3
MIC38C44-1YM-TR0.1432000.32500014SOIC.150In(3.90mm)Matte Tine3
MIC38C44AYM0.0750000.1632658SOIC3.90mm(.150in)NiPdAue4
MIC38C44AYM-TR0.0750000.2500008SOIC3.90mm(.150in)NiPdAue4
MIC38C44YM0.0750000.1632658SOIC3.90mm(.150in)NiPdAue4
MIC38C44YM-TR0.0750000.2500008SOIC3.90mm(.150in)NiPdAue4
MIC38C44AYMM0.0251000.1246008MSOP3x3x1.0mmNiPdAue4
MIC38C44AYMM-TR0.0251000.3347008MSOP3x3x1.0mmNiPdAue4
MIC38C44YMM0.0251000.1246008MSOP3x3x1.0mmNiPdAue4
MIC38C44YMM-TR0.0251000.3347008MSOP3x3x1.0mmNiPdAue4
MIC38C42/3/4/5 - BiCMOS Current-Mode PWM Controllers MIC38C45