OZ9955 схема включения, описание
Микросхемы OZ9955A и OZ9955B, Производитель- O2micro®
OZ9955A
FEATURES OZ9955A
• 50V internal MOSFET high frequency DC/DC converter controller
• Drives up to 8 strings in parallel
• Integrated LED current balance control circuit
• Integrated power MOSFET
• Up to 2.0MHz user-defi ned switching frequency
• Supports internal or external PWM dimming
• Over-voltage, over-current, output short circuit, and thermal protection
• LED fault status output
• Soft start function
GENERAL DESCRIPTION OZ9955A
OZ9955A is a high effi ciency, DC/DC controllers that drive up to eight (8) strings of LEDs
in parallel confi guration, with multiple LEDs in each string connected in series. It provides
eight (8) LED current sense inputs in an “OR” confi guration to improve backlight reliability.
This allows the backlight to remain functioning in the event that any string (s) is damaged
during normal operation.
OZ9955A can receive either a DC signal for internal Low frequency Pulse Width Modula-
tion (LPWM) or an external PWM signal.
This IC provides integrated circuits to balance the current fl ow through each LED string,
as well as, integrated power MOSFETs.
OZ9955B
FEATURES OZ9955B
• High frequency DC/DC power converter controller
• Drives up to 8 strings in parallel
• Supports SMBus, DPST and SMBus + DPST brightness control modes
• Supports SMBus protocol dimming control
• 256 step dimming control
• Integrated LED current balance control circuit
• Integrated power MOSFET
• Over-current, over-voltage, and thermal protection
• Soft start function
GENERAL DESCRIPTION OZ9955B
OZ9955B is a LED controller with SMBus interface that drives up to eight (8) strings
of LEDs in parallel confi guration, with multiple LEDs in each string connected in se-
ries. It is targeted for notebook/netbook applications using SMBus dimming control.
It provides eight (8) LED current sense inputs in an “OR” confi guration for improved
backlight reliability. This allows the backlight to remain functioning in the event that
any string (s) is damaged during normal operation.
This IC provides an integrated circuit to balance the current fl ow through each LED
string, as well as, the integrated power MOSFET.
Схема включения OZ9955A
Схема включения OZ9955B
Описание микросхем серии OZ99XX в формате PDF, скачать
