MT7811B
High Efficiency High Precision Buck Constant Current Driver
DESCRIPTION
MT7811B is a high precision LED constant
current controller operating at critical conduction
mode (CRM) with zero current switched-on and
peak current switched-off. It’s mainly targeted for
non-isolated buck LED power systems.
Critical conduction mode ensures that the
MT7811B turns on the internal power MOSFET
when the inductor current reaches zero, reducing
the power MOSFET switching loss, and
achieving more than 95% efficiency. With critical
conduction mode, and the input compensation,
MT7811B can achieve precise output current and
excellent line regulation and load regulation.
MT7811B embedded with internal power
MOSFET, it can achieve simplified peripheral
circuits and low BOM cost.
MT7811B has wide working voltage range, which
is suitable for full-range AC input. MT7811B
provides various protection features to improve
the system reliability, including over current
protection (OCP), short circuit protection (SCP),
adjustable over voltage protection (OVP) and
thermal adjustment, etc.
FEATURES
Critical Conduction Mode, insensitive to the
inductance.
High efficiency (up to 95%)
Highly accurate constant LED current
Cycle-by-cycle current limiting
LED short circuit protection
Adjustable OVP through external resistor
Leading edge blanking technique
Under-voltage lockout (UVLO) protection
Thermal adjustment
Available in SOP8 package
APPLICATIONS
LED bulb, LED tube, LED signal and
landscape lamp
LED stage light, LED candle light, LED corn
light, etc.
General purpose constant current source
Typical Application Circuit
VM
Rst1
Vin_ac
Rst2
C1 C2
CO
MT7811B
4 VCC
5
DRAIN
3 NC
6
DRAIN
2 VOVP
1 GND
7
NC
8
CS
Rcs
Email: sales@maxictech.com
Tel: 86-10-62662828
www.maxictech.com
Copy right © 2015 Maxic Technology Corporation
Rev. 1.15
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