EC3228 – High-Performance PWM Controller

General description

The EC3228 is a single-phase, constant-on-time, synchronous PWM controller, which drives N-channel MOSFETs. The  EC3228 steps down high voltage to generate low-voltage chipset or RAM supplies in notebook computers. The  EC3228  provides excellent transient response and accurate DC voltage output in either PFM or PWM Mode. In Pulse Frequency  Mode  (PFM), the EC3228 provides very high efficiency over light to heavy loads with loading-modulated  switching  frequencies. In PWM Mode, the converter works nearly at constant frequency for low-noise requirements. The  EC3228  is equipped with accurate positive current-limit, output under-voltage, and output over-voltage protections, perfect  for NB applications. The Power-On-Reset function monitors the voltage on VCC to prevent wrong operation during power-on. The EC3228 has a 1ms digital soft-start and built-in an integrated output discharge method for soft-stop. An  internal  integrated soft-start ramps up the output voltage with programmable slew rate to reduce the start-up current. A soft-stop function actively discharges the output capacitors  with controlled reverse inductor current.The EC3228 is available in 10pin TDFN 3×3 package.


Adjustable Output Voltage from +0.7V to +5.5V

0.7V Reference Voltage

±1% Accuracy Over-Temperature

Operates from an Input Battery Voltage Range of+1.8V to +32V

Power-On-Reset Monitoring on VCC Pin

Excellent Line and Load Transient Responses

PFM Mode for Increased Light Load Efficiency

Selectable PWM Frequency from 4 Preset Values

Integrated MOSFET Drivers

Integrated Bootstrap Forward P-CH MOSFET

Adjustable Integrated Soft-Start and Soft-Stop

Selectable Forced PWM or Automatic PFM/PWMMode

Power Good Monitoring

70% Under-Voltage Protection

125% Over-Voltage Protection

Adjustable Current-Limit Protection

Using Sense Low-Side MOSFET’s RDS(ON)

Over-Temperature Protection

TDFN-10 3×3 Package

Lead Free and Green Devices Available  (RoHS Compliant)



Table PC

Hand-Held Portable


LCD Monitor / TV

Battery Charger

ADSL Modem

l Telecom / Networking Equipment

Pin Configurations

Ordering info

Typical Applications circuit