原标题：NXP TEA1733(L) 低成本SMPS反激拓扑控制方案

　　nxp 公司的TEA1733(L) 是低成本GreenChip SMPS反激拓扑控制器,输入电压从12V到30V,起动和重起时的电流非常低,典型值为10uA,正常工作的电流低,无负载时为0.5mA,可编程软起动,主要用于高达75W高效高性价比的开关电源.本文介绍TEA1733(L)主要特性, 方框图, 典型配置图和典型应用电路图.

　　TEA1733T; TEA1733LT: GreenChip SMPS control IC

　　The TEA1733(L) is a low cost Switched Mode Power Supply (SMPS) controller IC intended for flyback topologies. The TEA1733(L) operates in fixed frequency mode. To reduce ElectroMagnetic Interference (EMI), frequency jitter has been implemented. For Continuous Conduction Mode (CCM) operation, slope compensation is integrated.

　　The TEA1733(L) IC features an OverPower Protection (OPP). The controller can be set to accept an overpower situation for a limited amount of time.

　　Two pins are reserved for protection purposes. Input UnderVoltage Protection (UVP) and OverVoltage Protection (OVP), output OVP and OverTemperature Protection (OTP) can be implemented with a minimal number of external components.

　　At low power levels the primary peak current is set to 25 % of the maximum peak current and the switching frequency is reduced to limit the switching losses. The combination of fixed frequency operation at high output power and frequency reduction at low output power provides high efficiency over the total load range.

　　The TEA1733(L) enables low cost, highly efficient and reliable supplies for power requirements up to 75 W to be designed easily and with a minimum number of external components.

　　TEA1733(L)主要特性:

　　SMPS controller IC enabling low cost applications

　　Large input voltage range (12 V to 30 V)

　　Very low supply current during start-up and restart (typically 10 mA)

　　Low supply current during normal operation (typically 0.5 mA without load)

　　Overpower or high/low line compensation

　　Adjustable overpower time-out

　　Adjustable overpower restart timer

　　Fixed switching frequency with frequency jitter to reduce EMI

　　Frequency reduction with fixed minimum peak current at low power operation to maintain high efficiency at low output power levels

　　Slope compensation for CCM operation

　　Low and adjustable OverCurrent Protection (OCP) trip level

　　Adjustable soft start

　　Two protection inputs (e.g. for input UVP and OVP, OTP and output OVP)

　　IC overtemperature protection

　　TEA1733(L)应用:

　　The devices can be used in all applications that require an efficient and cost-effective

　　power supply solution of up to 75 W.

　　图1.TEA1733(L)方框图

　　图2.TEA1733(L)典型配置图

　　图3.TEA1733(L)典型应用图