[AP1651BEL]

014003479-E-01

2014/10

- 1 -

1.

Genaral Description

The AP1651BEL (hereinafter referred to as the AP1651) is a current mode non-isolated low side buck

converter controller IC designed to support an LED general lighting application as a second stage (e.g. after

PFC stage). This IC provides "constant ripple control ", featuring the constant peak and bottom current of the

inductor which is sensed through low side sense resistors. This control scheme does not depend on either the

varying input voltage or the varying forward voltage of the LEDs, allowing the LED current to be obtained

with high stability.

The AP1651 supports two types of dimming; PWM dimming by pulse input and complex dimming by DC

input. Deep dimming down to 1% is achievable by using DC dimming. In addition, the DC dimming has an

even deeper dimming function by using an internal linear regulator for the LEDs. This "ultra-dimming"

which is supported from 500µA to 100µA is able to provide a new night light application.

This IC provides several protection function; over current protection, UVLO, and thermal shutdown for the

IC chip.

2.

Features



Low-side Switching Step-down Converter



Current mode

- Continuous Conduction Mode (CCM)

- Linear Regulator Mode (Automatic Mode Selection)



Operating Voltage Range

VDD = 11V to 26V

http://akm.transim.com/



Operating Temperature

Ta = - 40 to 105 °C



Dimming function

- External DC input (Complex Dimming 100% to 1% and Ultra-low current to 0%)

- Voltage Input of External Pulse (Dimming by PWM)



Protection function:

- Over Current Protection for External N-channel Power MOSFET

- Under Voltage Lockout Function (UVLO)

- CS pin Open Protection

- Thermal Shutdown (TSD)



Package

14-pin SOP

Dimmable LED driver IC for Lighting

AP1651BEL