Diodes Incorporated AP65550 Adaptive COT Step-down Converter
Diodes Inc. AP65550 Adaptive Constant On-time (COT) Step-down Converter offers high efficiency, excellent transient response, and high DC output accuracy for low-voltage regulation in digital TVs and monitors. The AP65550 constant-on-time control scheme handles wide input/output voltage ratios and has a low, external component count. The internal proprietary circuit enables AP65550 to adopt both low equivalent series resistance (ESR) output capacitors, such as SP-CAP or POSCAP, and ultra-low ESR ceramic capacitors. The adaptive on-time control supports a seamless transition between continuous conduction mode (CCM) at higher load conditions and discontinuous conduction mode (DCM) at lighter load conditions. DCM allows AP65550 to maintain high efficiency at light-load conditions. The AP65550 also features programmable soft-start, UVLO, OTP, and OCP to protect the circuit.
Features
- Fixed-frequency emulated constant on-time control
- Good stability independent of the output capacitor ESR
- Fast load transient response
- 65mΩ Internal high-side switch and 36mΩ internal low-side switch synchronous rectification
- 4.5V to 18V Wide input voltage range
- 0.76V to 6V Output voltage range
- 5A Continuous output current
- 650kHz Switching frequency
- Built-in over current limit
- Built-in thermal shutdown protection
- Programmable soft-start
- Pre-biased start-up
- Totally lead-free & fully RoHS compliant
- Halogen and antimony free, "Green" device
