TLD5190QV Datasheet, PDF (23/58 Pages) Infineon Technologies AG – H-Bridge DC/DC Controller for High Power LED Lighting

H-Bridge DC/DC Controller
TLD5190QV
Regulator Description
• M3 turns OFF, M4 turns ON until the end of the cycle (Recirculation)
• Switches M3 and M4 alternate, behaving like a typical synchronous boost Regulator (see Figure 10)
V_IN
ON
M1
HSGD1
SWN1
OFF M2
LSGD1
V_OUT
M4
L (2) Recirculation
OUT
HSGD2
SWN2
(1) Energizing
M3
LSGD2
ILOUT
M1
M1
M1
t
M1+M3 + M1+M3 + M1+M3 +
M4
M4
M4
R_SWCS
Figure 10 4 switches H-Bridge architecture in BOOST mode
Simplified comparison of 4 switches H-Bridge architecture to traditional asynchronous Boost approach.
• M2 is always OFF in this mode (open).
• M1 is always ON in this mode (closed connection of inductor to V_IN).
• M4 acts as a synchronous diode, with significantly lower conduction power losses (I² x R_DSON vs. 0.7V x I)
Note: Diode is source of losses and lower system efficiency!
M1 (ON)
V_IN
LOUT
M4
V_OUT
VIN
HSGD1
LSGD1
M2
(OFF)
HSGD2
M3
LSGD2
R_SWCS
LOUT
D1
M3
V_OUT
R_SWCS
a) 4 switch architecture BOOSTER
b) standard asynchronous BOOSTER
Figure 11 4 switches H-Bridge architecture in BOOST mode compared to standard async Booster
6.4.2
Buck mode (V_IN > V_OUT)
• M4 is always ON, M3 is always OFF
• Every cycle M2 turns ON and inductor current is sensed (valley current control)
• M2 stays ON until the lower reference threshold is reached across R_SWCS (Recirculation)
Data Sheet
23
Rev. 1.0, 2016-05-20