TL494: PWM Controller (up to 200 kHz)

The TL494 PWM Controller 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 PWM Controller 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 to VCC -2 V. The dead-time control comparator has a fixed offset that provides approximately 5% dead time. The on-chip oscillator can be bypassed by terminating RT to the reference output and providing a sawtooth input to CT, or it can drive the common circuits in synchronous multiple-rail power supplies.The uncommitted output transistors provide either common-emitter or emitter-follower output capability. This PWM Controller 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 PWM Controller is characterized for operation from 0C to 70C. The TL494I is characterized for operation from -40C to 85C. The TL494B is characterized for operation from -40C to 125C. The NCV494B is characterized for -40C to 125C and certified for automotive applications.

Features
  • Variable Frequency Operation (up to 200 KHz)
  • PWM Buck Controller Configuration
  • Complete Pulse Width Modulation Control Circuitry
  • On-Chip Oscillator with Master or Slave Operation
  • On-Chip Error Amplifiers
  • On-Chip 5.0 V Reference
  • Adjustable Deadtime Control
  • Uncommitted Output Transistors Rated to 500 mA Source or Sink
  • Output Control for Push-Pull or Single-Ended Operation
  • Undervoltage Lockout
  • Pb-Free Packages are Available*
Benefits
  • Optimize system size and efficiency
  • Simple to use in buck configuration
Applications
  • Off-line power supply
  • Buck converter
End Products
  • VPA (Vehicle Power Adapter)
  • LED Lighting
Application Notes (1)
Document TitleDocument ID/SizeRevisionRevision Date
A Simplified Power Supply Design Using the TL494 Control CircuitAN983/D (68.0kB)1
Package Drawings (2)
Document TitleDocument ID/SizeRevision
PDIP-16648-08 (34.2kB)V
SOIC 16 LEAD751B-05 (38.2kB)K
Data Sheets (1)
Document TitleDocument ID/SizeRevisionRevision Date
PWM Control Circuit (up to 200 kHz)TL494/D (144.0kB)6
Order Information
ProductStatusCompliancePackageMSL*ContainerBudgetary Price/Unit
TL494BDGLast ShipmentsPb-freeSOIC-16751B-051Tube48
TL494BDR2GActivePb-freeSOIC-16751B-051Tape and Reel2500$0.52
TL494CDGLast ShipmentsPb-freeSOIC-16751B-051Tube48
TL494CDR2GActivePb-freeSOIC-16751B-051Tape and Reel2500$0.4933
TL494CNGLast ShipmentsPb-free Halide freePDIP-16648-08NATube500
TL494INGLast ShipmentsPb-free Halide freePDIP-16648-08NATube500
Specifications
ProductTopologyPhasesControl ModeVCC Min (V)VCC Max (V)fSW Typ (kHz)tres Typ (ns)
TL494BDR2GFlyback Push-Pull Step-Up Forward Step-Down Half-Bridge1Voltage Mode740Up to 200100
TL494CDR2GForward Half-Bridge Flyback Step-Up Step-Down Push-Pull1Voltage Mode740Up to 200100
A Simplified Power Supply Design Using the TL494 Control Circuit TL494
SOIC 16 LEAD MC14504B
PDIP-16 MC10H350