UC28025 Series

Double ended economy high speed PWM controller

Catalog(4 parts)

Part	Function	Output Type	Output Configuration	Voltage - Supply (Vcc/Vdd)▲▼	Voltage - Supply (Vcc/Vdd)▲▼	Duty Cycle (Max)▲▼	Supplier Device Package	Number of Outputs▲▼	Package / Case	Control Features	Topology	Frequency - Switching▲▼	Frequency - Switching▲▼	Operating Temperature▲▼	Operating Temperature▲▼	Mounting Type	Package / Case▲▼
Texas Instruments UC28025DW Boost, Flyback, Forward Converter, Full-Bridge, Half-Bridge, Push-Pull Regulator Positive Output Step-Up, Step-Up/Step-Down DC-DC Controller IC 16-SOIC	Step-Up, Step-Up/Step-Down	Transistor Driver	Positive	30 V	9 V	0.44999998807907104 ul	16-SOIC	2 ul	16-SOIC	Current Limit, Enable, Frequency Control, Ramp, Soft Start	Boost, Flyback, Forward Converter, Full-Bridge, Half-Bridge, Push-Pull	460000 Hz	340000 Hz	105 °C	-40 °C	Surface Mount
Texas Instruments UC28025DWG4 Boost, Flyback, Forward Converter, Full-Bridge, Half-Bridge, Push-Pull Regulator Positive Output Step-Up, Step-Up/Step-Down DC-DC Controller IC 16-SOIC	Step-Up, Step-Up/Step-Down	Transistor Driver	Positive	30 V	9 V	0.44999998807907104 ul	16-SOIC	2 ul	16-SOIC	Current Limit, Enable, Frequency Control, Ramp, Soft Start	Boost, Flyback, Forward Converter, Full-Bridge, Half-Bridge, Push-Pull	460000 Hz	340000 Hz	105 °C	-40 °C	Surface Mount
Texas Instruments UC28025NG4 Boost, Flyback, Forward Converter, Full-Bridge, Half-Bridge, Push-Pull Regulator Positive Output Step-Up, Step-Up/Step-Down DC-DC Controller IC 16-PDIP	Step-Up, Step-Up/Step-Down	Transistor Driver	Positive	30 V	9 V	0.44999998807907104 ul	16-PDIP	2 ul	16-DIP	Current Limit, Enable, Frequency Control, Ramp, Soft Start	Boost, Flyback, Forward Converter, Full-Bridge, Half-Bridge, Push-Pull	460000 Hz	340000 Hz	105 °C	-40 °C	Through Hole	0.007619999814778566 m, 0.007619999814778566 m
Texas Instruments UC28025N Boost, Flyback, Forward Converter, Full-Bridge, Half-Bridge, Push-Pull Regulator Positive Output Step-Up, Step-Up/Step-Down DC-DC Controller IC 16-PDIP	Step-Up, Step-Up/Step-Down	Transistor Driver	Positive	30 V	9 V	0.44999998807907104 ul	16-PDIP	2 ul	16-DIP	Current Limit, Enable, Frequency Control, Ramp, Soft Start	Boost, Flyback, Forward Converter, Full-Bridge, Half-Bridge, Push-Pull	460000 Hz	340000 Hz	105 °C	-40 °C	Through Hole	0.007619999814778566 m, 0.007619999814778566 m

Key Features

• Peak Current Mode, Average Current Mode, or Voltage Mode (With FeedForward) Control MethodsPractical Operation Up to 1 MHz50-ns Propagation Delay to Output±1.5-A Peak Totem Pole Outputs9-V to 30-V Nominal Operational VoltageWide Bandwidth Error AmplifierFully Latched Logic With Double Pulse SuppressionPulse-by-Pulse Current LimitingProgrammable Maximum Duty Cycle ControlUndervoltage Lockout With HysteresisTrimmed 5.1-V Reference With UVLOSame Functionality as UC3823 and UC3825Peak Current Mode, Average Current Mode, or Voltage Mode (With FeedForward) Control MethodsPractical Operation Up to 1 MHz50-ns Propagation Delay to Output±1.5-A Peak Totem Pole Outputs9-V to 30-V Nominal Operational VoltageWide Bandwidth Error AmplifierFully Latched Logic With Double Pulse SuppressionPulse-by-Pulse Current LimitingProgrammable Maximum Duty Cycle ControlUndervoltage Lockout With HysteresisTrimmed 5.1-V Reference With UVLOSame Functionality as UC3823 and UC3825

Description

The UC28023 and UC28025 are fixed-frequency PWM controllers optimized for high-frequency switched-mode power-supply applications. The UC28023 is a single output PWM for single-ended topologies while the UC28025 offers dual alternating outputs for double-ended and full bridge topologies. Targeted for cost-effective solutions with minimal external components. UC2802x devices include an oscillator, a temperature compensated reference, a wide bandwidth error amplifier, a high-speed current-sense comparator, and high-current, active-high, totem-pole outputs to directly drive external MOSFETs. Protection circuitry includes a current limit comparator with a 1-V threshold, a TTL compatible shutdown port, and a soft-start pin which doubles as a maximum duty-cycle clamp. The logic is fully latched to provide jitter-free operation and prohibit multiple pulses at an output. An undervoltage lockout section with 800 mV of hysteresis assures low start-up current. During undervoltage lockout, the outputs are high impedance. Propagation delays through the comparators and logic circuitry have been minimized while maximizing bandwidth and slew rate of the error amplifier. Devices are available in the industrial temperature range of –40°C to 105°C. Package offerings are 16-pin SOIC (DW), or 16-pin PDIP (N) packages. The UC28023 and UC28025 are fixed-frequency PWM controllers optimized for high-frequency switched-mode power-supply applications. The UC28023 is a single output PWM for single-ended topologies while the UC28025 offers dual alternating outputs for double-ended and full bridge topologies. Targeted for cost-effective solutions with minimal external components. UC2802x devices include an oscillator, a temperature compensated reference, a wide bandwidth error amplifier, a high-speed current-sense comparator, and high-current, active-high, totem-pole outputs to directly drive external MOSFETs. Protection circuitry includes a current limit comparator with a 1-V threshold, a TTL compatible shutdown port, and a soft-start pin which doubles as a maximum duty-cycle clamp. The logic is fully latched to provide jitter-free operation and prohibit multiple pulses at an output. An undervoltage lockout section with 800 mV of hysteresis assures low start-up current. During undervoltage lockout, the outputs are high impedance. Propagation delays through the comparators and logic circuitry have been minimized while maximizing bandwidth and slew rate of the error amplifier. Devices are available in the industrial temperature range of –40°C to 105°C. Package offerings are 16-pin SOIC (DW), or 16-pin PDIP (N) packages.