The GL494 incorporates on a single monolithic chip all the functions required in the construction of a pulse-width modulation control circuit.
Designed primarily for power supply control, the GL494 contains an on-chip 5-volt regulator, two error amplifiers, adjustable oscillator, deadtime control comparator, pulse-steering flip-flop, and output control circuitry.
Features 1. Complete PWM Power Control Circuitry 2. Uncommitted Outputs for 200mA Sink or Source 3. Output Control Selects Single-Ended or Push-Pull Operation 4. Internal Circuitry Prohibits Double Pulse at Either Output 5. Internal Regulator Provides a Stable 5V Reference Supply 6. Variable Dead-Time Provides Control Over Total Range Other data sheets within the file : L494
SAQ8818 application is a powerful switching power supply solutions.
The design for LCD products with CCFL backlight, EEFL backlight, LED backlight management, and computer Power supply, home appliances, communication products, such as switching power supplies, DC-DC converter control, product features full compatibility High. 1. This product includes single-ended PWM, double-ended PWM, push-pull, half-bridge, and full-bridge circuits, with efficiency up to 90%.
2. 5-45V ultra-wide operating voltage, unique in the industry, greatly facilitates product design and improves product reliability.
3. Drive current up to 3A, extremely high symmetry, and controllable drive level. It can directly drive P, N-type MOSFETs and transistors, and has its own corresponding circuit platform technology. Features
1. Supply voltage 5-45V. 2. Single-ended PWM, double-ended PWM, push-pull, half-bridge, full-bridge circuits are optional. 3. Various protection function designs, and can set protection lock and self-recovery. 4. 3A drive current, can directly push MOSFET and triode, voltage and current mode are automatically switched. 5. Extremely high conversion efficiency. 6. The frequency setting adopts dual mode of capacitance and resistance, which can achieve high precision frequency. The on-chip oscillator can perform master-slave operation. 7. ESD protection design, up to 20KV. 8. ROHS standard, meet environmental requirements.
1. P OUT1 O Output driver P1 2. P OUT2 O Output driver P2 3. N OUT2 O Output driver N2 4. VCC – The power supplies PIN 5. SLECT O To Set the output 6. VREF O The voltage for reference 7. PR SLECT I To set the lever of the Open lamp protection 8. OLP I The PIN of the Open lamp protection 9. IN+ I The inverting input of the error amplifier for + 10. IN- I The inverting input of the error amplifier for – 11. COMP O Output of the error amplifier 12. CLAMP O Over voltage clamping 13. CTOSC I/O Set frequency of main frequency for PWM controller 14. LOAD/RT I/O An external resistor connected to change frequency 15. GND – The ground PIN 16. N OUT1 O Output driver N1
Functional block diagram
1. CCFL backlight system. 2. EEFL backlight system. 3. LED backlight system. 4. laptop. 5. LCD monitors and LCD TV products. 6. Mobile TV, mobile DVD. 7. Vehicle display system. 8. ATM terminal. 9. POS terminal. 10. 5-1000W DC-DC switching power supply.