H6849 Datasheet, PDF (1/13 Pages) Hi-Sincerity Mocroelectronics – Novel Low Cost Green-Power PWM Controller

HI-SINCERITY
MICROELECTRONICS CORP.
Spec. No. : IC200804
Issued Date : 2008.09.19
Revised Date :
Page No. : 1/13
H6849 Series
Novel Low Cost Green-Power PWM Controller
Features
z Low Cost, PWM&PFM&CRM
z Low Start-up Current (about 10μA)
z Low Operating Current (about 2mA)
z Current Mode Operation
z Under Voltage Lockout (UVLO)
z Built-in Synchronized Slope
Compensation
z Programmable PWM Frequency
z Leading edge Blanking on Sense input
z Constant output power limiting for
universal AC input
z Cycle-by-cycle current limiting
z Clamped gate output voltage 16.5V
z Over voltage protect 26.7V
z High-Voltage CMOS Process with ESD
z SOT-23-6L、SOP-8 & DIP-8 Pb-Free
Packaging
z Compatible with SG5701 & SG5848 &
LD7535 &OB2263/2263
Applications
z Switching AC/DC Adaptor
z Battery Charger
z Open Frame Switching Power Supply
z 384X Replacement
General Description
The H6849 is a highly integrated low cost
current mode PWM controller, which is ideal
for small power current mode of offline
AC-DC fly-back converter applications.
Making use of external resistors, the IC
changes the operating frequency and
automatically enters the PFM/CRM under
light-load/zero-load conditions. This can
minimize standby power consumption and
achieve green-power functions. With a very
low start-up current, the H6849 could use a
large value start-up resistor (1.5Mohm).
Built-in synchronized slope compensation
enhances the stability of the system and
avoids sub-harmonic oscillation. Dynamic
peak limiting circuit minimizes output power
change caused by delay time of the system
over a universal AC input range. Leading
edge blanking circuit on current sense input
could remove the signal glitch due to
snubber circuit diode reverse recovery and
thus greatly reduces the external
component count and system cost in the
design. Pulse-by-pulse current limiting
ensures safe operation even during
short-circuit.
The H6849 offers more protection like OVP
(Over Voltage Protection) and OCP (Over
current protection). The H6849’s output
driver is clamped to maximum 16.5V to
protect the power MOSFET. Excellent EMI
performance is achieved soft switching
control at the totem pole gate driver output.
H6849 is offered in SOT-23-6, SOP-8 and
DIP-8 packages.
H6849P, H6849S,H6849NF
HSMC Product Specification