HT2269

1/13

Current Mode PWM Controller

www.hotchip.com.cn

Ver1.0

GENERAL DESCRIPTION

HT2269 is a highly integrated current mode

PWM control IC optimized for high performance,

low standby power and cost effective offline flyback

converter applications.

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.

VDD low startup current and low operating

current contribute to a reliable power on startup

design with HT2269. A large value resistor could

thus be used in the startup circuit to minimize the

standby power.

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 input removes the signal glitch due to

snubber circuit diode reverse recovery. This greatly

helps to reduce the external component count and

system cost in application.

HT2269 offers complete protection coverage

with automatic self-recovery feature including

Cycle-by-Cycle current limiting (OCP), over load

protection (OLP), over temperature protection

(OTP), VDD over voltage protection (OVP) and

under voltage lockout (UVLO). The Gate-drive

output is clamped at 18V to protect the power

MOSFET.

In HT2269, OCP threshold slope is internally

optimized to reach constant output power limit over

universal AC input range.

Excellent EMI performance is achieved

frequency shuffling technique together with soft

switching control at the totem pole gate drive output.

The tone energy at below 20KHZ is minimized

in operation. Consequently, audio noise erformance

is greatly improved. HT2269 is offered in both SOP-

8 and DIP-8 packages.

FEATURES

◆ Extended Burst Mode Control For Improved

Efficiency and Minimum Standby Power Design.

◆ Audio Noise Free Operation

◆ External Programmable PWM Switching

Frequency

◆ Internal Synchronized Slope Compensation

◆ Low VIN/VDD Startup Current(6.5uA) and Low

Operating Current (2.3mA)

◆ Leading Edge Blanking on Current Sense Input

◆ Complete Protection Coverage With Auto Self-

Recovery

◆ External Programmable Over Temperature

Protection (OTP)

◆ On-chip VDD OVP for System OVP Under

Voltage Lockout with Hysteresis (UVLO)

◆ Gate Output Maximum Voltage Clamp (18V)

◆ Line Compensated Cycle-by-Cycle Over-current

Threshold Setting For Constant Output Current

Limiting Over Universal Input Voltage Range

(OCP)

◆ Over Load Protection. (OLP)

APPLICATIONS

◆ Laptop Power Adaptor

◆ PC/TV/Set-Top Box Power

◆ Supplies Open-frame SMPS

◆ Battery Charge