MIC38C42/3/4/5 Micrel, Inc. MIC38C42/3/4/5
BiCMOS Current-Mode PWM Controllers General Description Features The MIC38C4x are п¬Ѓxed frequency, high performance, current-mode PWM controllers. MicrelвЂ™s BiCMOS devices are
pin compatible with 384x bipolar devices but feature several
Undervoltage lockout circuitry allows the вЂ™42 and вЂ™44 versions
to start up at 14.5V and operate down to 9V, and the вЂ™43 and
вЂ™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 50ВµA 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 efп¬Ѓciency, especially at lower supply voltages. The MIC38C4x also features
a trimmed oscillator discharge current and bandgap reference.
The MIC38C4x denotes 8-pin plastic DIP, SOIC, and MSOP
packages. MIC384Cx-1 denotes 14-pin plastic DIP and
SOIC packages. 8-pin devices feature small size, while 14pin devices separate the analog and power connections for
improved perfomance and power dissipation. Fast 40ns output rise and 30ns output fall times вЂ“40В°C to +85В°C temperature range
meets UC284x speciп¬Ѓcations High-performance, low-power BiCMOS Process Ultralow start-up current (50ВµA typical) Low operating current (4mA typical) CMOS outputs with rail-to-rail swing в‰Ґ 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 Applications Current-mode, off-line, switched-mode power supplies
Current-mode, dc-to-dc converters.
Step-down вЂњbuckвЂќ regulators
Step-up вЂњboostвЂќ regulators
Flyback, isolated regulators …