SGLS265A – NOVEMBER 2004 – REVISED MAY 2011
IMPROVED CURRENT MODE PWM CONTROLLER
Check for Samples: UC2856Q
• Pin-for-Pin Compatible With the UC2846
• 65-ns Typical Delay From Shutdown to
Outputs and 50-ns Typical Delay From
Sync to Outputs
• Improved Current Sense Amplifier With
Reduced Noise Sensitivity
• Differential Current Sense With 3-V
Common Mode Range
• Trimmed Oscillator Discharge Current for
Accurate Deadband Control
• Accurate 1-V Shutdown Threshold
• High Current Dual Totem Pole
Outputs (1.5-A peak)
• TTL Compatible Oscillator SYNC Pin
• 4-kV ESD Protection
The UC2856 is a high performance version of the popular UC2846 series of current mode controllers, and is
intended for both design upgrades and new applications where speed and accuracy are important. All input to
output delays have been minimized, and the current sense output is slew rate limited to reduce noise sensitivity.
Fast 1.5-A peak output stages have been added to allow rapid switching of power FETs.
A low impedance TTL compatible sync output has been implemented with a 3-state function when used as a
Internal chip grounding has been improved to minimize internal noise caused when driving large capacitive
loads. This, in conjunction with the improved differential current sense amplifier, results in enhanced noise
Other features include a trimmed oscillator current (8%) for accurate frequency and dead time control; a 1 V, 5%
shutdown threshold; and 4 kV minimum ESD protection on all pins.
–40°C to 125°C
Tape and reel
(1) Package drawings, standard packing quantities, thermal data, symbolization, and PCB design
guidelines are available at www.ti.com/sc/package.
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Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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