LTC3722-2_15 Datasheet, PDF (4/28 Pages) Linear Technology – Synchronous Dual Mode Phase Modulated Full Bridge Controllers

LTC3722-1/LTC3722-2
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T_A = 25°C. V_CC = 9.5V, C_T = 270pF, R_DPRG = 60.4k, R_SPRG = 100k, unless
otherwise noted (Note 6).
SYMBOL PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Reference
V_REF
REFLD
REFLN
REFTV
Initial Accuracy
Load Regulation
Line Regulation
Total Variation
T_A = 25°C, Measured on V_REF
Load on V_REF = 100µA to 5mA
V_CC = 6.5V to 9.5V
Line, Load
4.925 5.00 5.075
V
2
15
mV
0.9
10
mV
l 4.900 5.000 5.100
V
REFSC Short-Circuit Current
Outputs
V_REF Shorted to GND
18
30
45
mA
OUTH(x) Output High Voltage
OUTL(x) Output Low Voltage
R_HI(x)
R_LO(x)
t_r(x)
t_f(x)
SDEL
Pull-Up Resistance
Pull-Down Resistance
Rise Time
Fall Time
SYNC Driver Turn-0ff Delay
Current Limit and Shutdown
I_OUT(x) = –50mA
I_OUT(x) = 50mA
I_OUT(x) = –50mA to –10mA
I_OUT(x) = –50mA to –10mA
C_OUT(x) = 50pF (Note 8)
C_OUT(x) = 50pF (Note 8)
R_SPRG = 100k
7.9
8.4
V
0.6
1
V
22
30
Ω
12
20
Ω
5
15
ns
5
15
ns
180
ns
CLPP
Pulse by Pulse Current Limit Threshold Measured on CS
LTC3722E-1/LTC3722I-1/LTC3722E-2/LTC3722I-2
LTC3722H-1
270
300
330
mV
270
300
340
mV
CLSD Shutdown Current Limit Threshold
Measured on CS
0.55 0.65 0.73
V
CLDEL Current Limit Delay to Output
100mV Overdrive on CS (Notes 3, 7)
80
ns
SSI
Soft-Start Current
SS = 2.5V
7
12
17
µA
SSR
Soft-Start Reset Threshold
Measured on SS
0.7
0.4
0.1
V
FLT
Fault Reset Threshold
Measured on SS
4.5
3.9
3.5
V
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: Sync amplitude = 5V_P-P , pulse width = 50ns. Verify output (A-F)
frequency = one-half sync frequency.
Note 3: Includes leading edge blanking delay, R_LEB = 20k.
Note 4: FB is driven by a servo-loop amplifier to control V_COMP for these
tests.
Note 5: Set FB to –0.3V, 2.5V and insure that COMP does not phase invert.
Note 6: The LTC3722 is tested under pulsed load condition such that
T_J ≈ T_A. The LTC3722E-1/LTC3722E-2 are guaranteed to meet performance
specifications from 0°C to 85°C. Specifications over the –40°C to
85°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LTC3722I-1/LTC3722I-2 are guaranteed over the –40°C to 85°C operating
junction temperature range and the LTC3722H-1 is guaranteed over the
–40°C to 150°C operating junction temperature range.
High junction temperatures degrade operating lifetimes; operating lifetime
is derated for junction temperatures greater than 125°C. Note that the
maximum ambient temperature consistent with these specifications is
determined by specific operating conditions in conjunction with board
layout, the rated package thermal impedance and other environmental
factors.
Note 7: Guaranteed by design, not tested in production.
Note 8: Rise time is measured from the 10% to 90% points of the rising
edge of the driver output signal. Fall time is measured from the 90% to
10% points of the falling edge of the driver output signal.
372212fb
4
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