1. General description
The TEA1738(L) is a low cost Switched Mode Power Supply (SMPS) controller IC
intended for flyback topologies. The TEA1738(L) operates in peak current and frequency
control mode. Frequency jitter has been implemented to reduce ElectroMagnetic
Interference (EMI). Slope compensation is integrated for Continuous Conduction Mode
(CCM) operation.
The TEA1738(L) IC includes OverPower Protection (OPP). This enables the controller to
operate under overpower situations for a limited amount of time.
Two pins, VINSENSE and PROTECT, are reserved for protection purposes. Input
UnderVoltage Protection (UVP), output OverVoltage Protection (OVP) and
OverTemperature Protection (OTP) can be implemented using 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 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 TEA1738(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.
2. Features and benefits
2.1 Features
SMPS controller IC enabling low-cost applications
Large input voltage range (12 V to 30 V)
Integrated OverVoltage Protection (OVP) on pin VCC
Very low supply current during start-up and restart (10 μA typical)
Low supply current during normal operation (0.55 mA typical 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 at medium power operation to maintain high efficiency
TEA1738T; TEA1738LT
GreenChip SMPS control IC
Rev. 2 — 14 January 2011 Product data sheet
