【概要】
The TL494 device incorporates all the functions required in the construction of a pulse-width-modulation (PWM) control circuit on a single chip. Designed primarily for power-supply control, this device offers the flexibility to tailor the power-supply control circuitry to a specific application.
The TL494 device contains two error amplifiers, an on-chip adjustable oscillator, a dead-time control (DTC) comparator, a pulse-steering control flip-flop, a 5-V, 5%-precision regulator, and output-control circuits.
The error amplifiers exhibit a common-mode voltage range from -0.3 V toVCC - 2 V. The dead-time control comparator has a fixed offset that providesapproximately 5% dead time. The on-chip oscillator can be bypassed by terminatingRT to the reference output and providing a sawtooth input to CT, or itcan drive the common circuits in synchronous multiple-rail power supplies.
The uncommitted output transistors provide either common-emitter or emitter-follower output capability. The TL494 device provides for push-pull or single-ended output operation, which can be selected through the output-control function. The architecture of this device prohibits the possibility of either output being pulsed twice during push-pull operation.
The TL494C device is characterized for operation from 0°C to 70°C. TheTL494I device is characterized for operation from -40°C to 85°C.
【特長】
- Complete PWM Power-Control Circuitry
- Uncommitted Outputs for 200-mA Sink or Source Current
- Output Control Selects Single-Ended or Push-Pull Operation
- Internal Circuitry Prohibits Double Pulse at Either Output
- Variable Dead Time Provides Control Over Total Range
- Internal Regulator Provides a Stable 5-V Reference Supply With 5% Tolerance
- Circuit Architecture Allows Easy Synchronization
【主な仕様】
Topology | Boost Buck Flyback Forward Full-Bridge Half-Bridge Push-Pull |
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Control Method | Voltage |
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Vin(Min)(V) | -0.3 |
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Vin(Max)(V) | 38 |
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Frequency(Max)(kHz) | 300 |
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UVLO Thresholds On/Off(V) | N/A |
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Duty Cycle(Max)(%) | 45 |
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Gate Drive(Typ)(A) | 0.2 |
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Features | Adjustable Switching Frequency Error Amplifier Multi-topology |
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Operating Temperature Range(C) | 0 to 70 |
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Pin/Package | 16SO |
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