Diodes AT5503 User Manual
Preliminary datasheet, General description, Features

Preliminary Datasheet
18V, 3A Synchronous DC-DC Buck Converter AT5503
Mar. 2013 Rev. 1. 0 BCD Semiconductor Manufacturing Limited
1
General Description
The AT5503 is a 500kHz fixed frequency, current
mode, PWM synchronous buck (step-down) DC-DC
converter, capable of driving a 3A load with high
efficiency, excellent line and load regulation. The
AT5503 exhibits high efficiency at light load. The
device integrates N-channel power MOSFET switch
with low on-resistance. Current mode control
provides fast transient response and cycle-by-cycle
current limit.
The AT5503 employs complete protection to ensure
system security, including output Over Voltage
Protection, input Under Voltage Lock Out,
programmable soft-start, Over Temperature
Protection and hiccup mode Short Circuit Protection.
This IC is available in PSOP-8 package.
Features
• Input Voltage Range: 4.5V to 18V
• Fixed 500kHz Frequency
• High Efficiency at Light Load
• Output Current: 3A
• Current Mode Control
• Built-in Over Current Protection
• Built-in Thermal Shutdown Function
• Built-in UVLO Function
• Built-in Over Voltage Protection
• Programmable Soft-start
• Hiccup Mode SCP
Applications
• Monitor
• TV
• STB
• Datacom
Figure 1. Package Type of AT5503
PSOP-8