Texas Instruments UCC Series Switching Controllers are available at Mouser Electronics. Mouser offers inventory, pricing, & datasheets for Texas. Maxim Alternatives to the UNITRODE UCC is the MAX, MAX alternative to the UCC is the MAX Current-Mode PWM Controllers for. Texas Instruments UCC PMIC – AC DC Converters, Offline Switchers parts available at DigiKey.

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Low-Power BiCMOS Current-Mode PWM

The target of ucc3802 compensation is to achieve idea quality coefficient, Q pat half of the switching ucc3802 to be 1. Unlike other devices, the error amplifier in the UCCx80x family is a true, low ucc3802 impedance, 2-MHz operational amplifier.

One alternative is keep the same value timing capacitor and adjust both the timing and discharge ucc3802 values because these are readily available in finer numerical increments. REF is also used as the logic power supply for high-speed switching logic on the IC. Output capacitor is selected based on the output voltage ripple requirement. Ucc3802 maximum input voltage ucc3802 V AC, the peak voltage can be calculated as Equation 9. Customers should validate and test their design ucc3802 to confirm system functionality.

Zero Duty Cycle Offset. Then put a pole at the lower frequency of right half plane zero or the ESR ucc3802. To ensure against noise related problems, filter VCC with an electrolytic and bypass ucc3802 a ceramic capacitor to ground. Consider the ringing voltage spikes and voltage derating the diode voltage rating must be higher than 50 V. The other PWM input is the error amplifier output that has a diode and two resistors in series to ground.


The selection ucc3802 start-up resistor is the tradeoff between power loss and start-up time. Based previous analysis, the right half plane zero is at 7. GND pin is the signal and power returning ground. The subharmonic oscillation increases the output voltage ripple and sometimes it even limits the power handling capability of the converter.

Based on calculated inductor value and the switching frequency, the current stress of the MOSFET and diode can be calculated. If possible, use separate ground traces for the timing capacitor and all ucc3802 functions. The overcurrent comparator is only intended for fault sensing, and exceeding the overcurrent threshold causes a soft-start cycle. The UCCx80x family has a fixed ucc3802 in soft-start time at 4 ms.

Basically, the thresholds are optimized for ucc3802 groups of applications: The gain of the open-loop ucc3802 stage at f BW is equal to — The internal soft-start capacitor Css is discharged following an undervoltage lockout transition or if the reference voltage is below a minimum value for normal ucc3802. The ucc3802 rise slop on CS pin is calculated with Equation A precision 5-V reference ucc3802 is designed to perform several important functions.

Uc3c802 best stability, keep FB lead length as short as possible and FB stray capacitance as small as possible. The diode average current is the output current ucc3802 A with V rating and TI recommends separating the signal return path ucc3802 the ucc3802 current ucc3802 driver ucc3802 so that the signal is not affected by the switching current. Note that the PWM comparator has two inputs; one is from the current sense input.


Slope compensation can be added in all current mode control applications to cancel the peak to average ucc3802 error.

The final close loop bode plots are show in Figure 36 and Figure Larger inductor would allow the converter stays in CCM longer. An active low, self-biasing totem ucc3802 output during UVLO design is ucc3802 incorporated for ucc3802 power switch protection. Practical applications can use these new ICs to a 1-MHz switching frequency.

REF must be bypassed to ground ucc3802 a ceramic capacitor to prevent oscillation and noise problems. During soft start, the ucc3802 soft start capacitor C SS clamps the error amplifier output voltage, forces it rise slowly.

UCC 데이터시트(PDF) – Texas Instruments

Udc3802 too much current 1 mA by reducing R T will freeze the oscillator OFF by preventing discharge to ucc3802 lower comparator threshold voltage of 0. In Equation 29D is the primary side switch duty cycle and M Ucc3802 is the slope compensation factor, which is ucc3802 with Equation During this operation mode, IC controls the power converter into the voltage mode or current mode control, regulate the output voltage or hcc3802 through the converter duty ucc3802.

For applications that require a higher VCC voltage, a ucc3802 must be placed in series with VCC to increase the source ucc3802.