UCD8220
www.ti.com SLUS652D – MARCH 2005 – REVISED OCTOBER 2006 DIGITALLY MANAGED PUSH-PULL ANALOG PWM CONTROLLERS
FEATURES APPLICATIONS For Digitally Managed Power Supplies Using
ВµCs or the TMS320 в„ў DSP Family Voltage or Peak Current Mode Control with
Cycle-by-Cycle Current Limiting Clock input from Digital Controller to set
Operating Frequency and Max Duty Cycle Analog PWM Comparator 2-MHz Switching Frequency 110-V Input Startup Circuit and Thermal
Shutdown (UCD8620) Internal Programmable Slope Compensation 3.3-V, 10-mA Linear Regulator DSP/ВµC Compatible Inputs Dual 4-A TrueDriveв„ў High Current Drivers 10-ns Typical Rise and Fall Times with 2.2-nF 25-ns Input-to-Output Propagation Delay 25-ns Current Sense-to-Output Propagation
Delay Programmable Current Limit Threshold Digital Output Current Limit Flag 4.5-V to 15.5-V Supply Voltage Range Rated from -40C to 105C 1 23 Digitally Managed Switch Mode Power
Supplies
Push-Pull, Half-Bridge, or Full-Bridge
Converters
Battery Chargers DESCRIPTION
The UCD8220 analog pulse-width modulator device
is used in digitally managed power supplies using a
microcontroller or the TMS320в„ў DSP family.
UCD8220 ia a double-ended PWM
configured with push-pull drive logic. controller Systems using the UCD8220 device close the PWM
feedback loop with traditional analog methods, but
the UCD8220 controller includes circuitry to interpret
a time-domain digital pulse train. The pulse train
contains the operating frequency and maximum duty
cycle limit which are used to control the power supply
operation. This eases implementation of a converter …
