LCS700-708
Conditions
SOURCE = 0 V; TJ = 0 to 100 °C
Parameter
Symbol
Min
Typ
Max
Units
VCC = 12 V, VCCH = 12 V
(Unless Otherwise Specified)
LLC Oscillator (cont.)
IFB Threshold
Hysteresis
IBURST(HYST)
VBT1
ISTART is IBURST(HYST) below ISTOP
5
6.25
95
8
% of IDT/BF
Required VDT/BF at start-up to enable burst
setting BT1
93.5
88.5
83.5
96.3
91.3
86.3
DT/BF Voltage to
Program Burst Setting
Required VDT/BF at start-up to enable burst
setting BT2
VBT2
90
% of VREF
Required VDT/BF at start-up to enable burst
setting BT3
VBT3
85
Time Constant for the
This time constant must be less than the
specified maximum to ensure correct
setting of burst mode.
Combination of RFMAX
,
RCDT/BF
100
430
ms
RBURST and the Decoup-
ling Cap on DT/BF
Determines the maximum control
frequency that can be set by IFB.
FB Current Maximum
IFB
IFB
100
%IDT/BF
mA
FB Control
Current Range
IFB is limited by the current into DT/BF
15
FB input appears as RIN(FB) in series with
FB Virtual Voltage
VFB
0.65
2.5
V
VFB. 30 mA < IFB < IDT/BF
FB input appears as RIN(FB) in series with
FB Input Resistance
RIN(FB)
kW
VFB. 30 mA < IFB < IDT/BF
FB input appears as RFB(SS) in series with
VREF during the soft-start delay interval or
when OV/UV < VSD or OV/UV > VOV
FB Input Resistance
During Soft-Start
RFB(SS)
750
W
Over-Current Protection
Fast Over-Current
Fault Voltage
Threshold4
VIS(F)
0.855
0.455
0.905
0.955
0.555
V
Slow Over-Current
Fault Voltage
Threshold
7 LLC clock cycle debounce
VIS(S)
0.505
30
V
Minimum time VIS exceeds VIS(F)/VIS(S) per
cycle to trigger fault protection
Over-Current Fault
Pulse Width
tIS
ns
Over-Temperature Protection
Over-Temperature
TOT
140
°C
Shutdown ThresholdA
NOTES:
A. Guaranteed by design.
B. Typical apparent dead-time at the HB pin under resonant ZVS conditions.
C. VCC/VCCH operating range to achieve power capabilities specified in data sheet power table.
22
Rev. B 062011
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