Excellent EMI performance is achieved with
frequency shuffling technique together with soft
switching control at the totem pole gate drive
output.
GENERAL DESCRIPTION
AMS2263 is a highly integrated current mode PWM
control IC optimized for high performance, low
standby power and cost effective offline flyback
converter applications in sub 30W range.
Tone energy at below 20KHZ is minimized in the
design and audio noise is eliminated during
operation. AMS2263 is offered in SOT23-6, SOP-8
and DIP-8 packages.
PWM switching frequency at normal operation is
externally programmable and trimmed to tight
range. At no load or light load condition, the IC
operates in extended ‘burst mode’ to minimize
switching loss. Lower standby power and higher
conversion efficiency is thus achieved.
FEATURES
Extended Burst Mode Control For Improved
Efficiency and Minimum Standby Power
Design.
VDD low startup current and low operating
current contribute to a reliable power on startup
design with AMS2263. A large value resistor could
thus be used in the startup circuit to minimize the
standby power.
Audio Noise Free Operation
External Programmable PWM Switching
Frequency
Internal Synchronized Slope Compensation
Low VDD Startup Current and Low Operating
Current (1.4mA)
The internal slope compensation improves
system large signal stability and reduces the
possible sub-harmonic oscillation at high PWM
duty cycle output. Leading-edge blanking on
current sense(CS) input removes the signal glitch
due to snubber circuit diode reverse recovery and
thus greatly reduces the external component
count and system cost in the design.
Leading Edge Blanking on Current Sense
Input
Good Protection Coverage With Auto
Self-Recovery
VDD Over Voltage Clamp and Under Voltage
Lockout with Hysteresis (UVLO)
Gate Output Maximum Voltage Clamp (18V)
Line Input Compensated Cycle-by-Cycle
Over-current Threshold Setting For Constant
Output Power Limiting Over Universal Input
Voltage Range.
AMS2263 offers complete protection coverage with
automatic self-recovery feature including
Cycle-by-Cycle current limiting (OCP), over load
protection (OLP), VDD over voltage clamp and
under voltage lockout (UVLO). The Gate-drive
output is clamped to maximum 18V to protect the
power MOSFET.
Overload Protection (OLP)
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Advanced Monolithic Systems http://www.ams-semitech.com