LTC3765_15 Datasheet, PDF (3/24 Pages) Linear Technology – Active Clamp Forward Controller and Gate Driver

LTC3765
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T_A = 25°C (Note 2). V_CC = 12V unless otherwise noted.
SYMBOL PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Gate Drivers (PG, AG, DELAY)
V_OHPG
I_PUPG
R_PDPG
t_rPG
t_fPG
R_PUAG
R_PDAG
t_DAG
t_DPG
PG High Output Voltage
PG Peak Pull-Up Current
PG Pull-Down Resistance
PG Rise Time
PG Fall Time
AG Pull-Up Resistance
AG Pull-Down Resistance
AG Turn-On Delay Time
PG Turn-On Delay Time
Oscillator (FS/UV) and Soft-Start (SSFLT)
I_PG = –100mA
I_PG = 100mA
20% to 80%, C_PG = 4.7nF
20% to 80%, C_PG = 4.7nF
I_AG = –10mA
I_AG = 10mA
R_DELAY = 0Ω
R_DELAY = 10kΩ
R_DELAY = 50kΩ
11
V
2.5
A
1.3
Ω
20
ns
20
ns
12
Ω
9
Ω
180
ns
40
ns
120
140 160
ns
390
460 530
ns
f_OSC
Oscillator Frequency
DC_MAX
V_FSUVH
I_FSUV
I_SS(C)
Oscillator Maximum Duty Cycle
FS/UV Output High
FS/UV Pull-Up Current
Soft-Start Charge Current
I_SS(D)
Soft-Start Discharge Current
V_FLTH
Fault Output High
V_FLTD
Fault Detection Voltage
Overcurrent (I_S+, I_S–) and Direct Flux Limit (I_SMAG, R_CORE)
V_IS
V_ISMAG–
V_ISMAG+
Overcurrent Threshold
I_SMAG Limit Negative Threshold
I_SMAG Limit Positive Threshold
M_ISMAG
I_SMAG Replicated Slope
R_FS = 75kΩ
R_FS = 10kΩ
V_SSFLT = 3.5V
V_RUN = 1V
V_RUN = 1V, V_FS/UV = 1.5V
V_RUN = 1.3V, V_SSFLT = 1V
V_RUN ≥ 3.75V, V_SSFLT = 1V
Timing Out After Fault, V_SSFLT = 2V
V_CC = 6.7V
V_ISTH = V_IS+–V_IS–
Relative to SGND or V_CC
Relative to SGND or V_CC
R_CORE = 50kΩ, V_RUN = 1.25V
R_CORE = 50kΩ, V_RUN = 6.25V
R_CORE = 10kΩ, V_RUN = 1.25V
R_CORE = 10kΩ, V_RUN = 6.25V
75
kHz
430
kHz
70
%
5
V
50
µA
–4
µA
–1.6 –0.5
µA
1.25
µA
5.75
6.5
V
5
5.5
V
l 130
–1.15
0.85
150 170
–1 –0.85
1
1.15
75
375
335
1700
mV
V
V
mV/µs
mV/µs
mV/µs
mV/µs
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: The LTC3765 is tested under pulsed-load conditions such that
T_J ≈ T_A. The LTC3765E is guaranteed to meet specifications from
0°C to 85°C junction temperature. Specifications over the –40°C to
125°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LTC3765I is guaranteed over the –40°C to 125°C operating junction
temperature range, the LTC3765H is guaranteed over the –40°C to 150°C
operating junction temperature range and the LTC3765MP is tested and
guaranteed over the –55°C to 150°C operating junction temperature range.
High junction temperatures degrade operating lifetimes; operating lifetime
is derated for junction temperature greater than 125°C. The junction
temperature (T_J) is calculated from the ambient temperature (T_A) and
power dissipation (P_D) according to the formula:
T_J = T_A + (P_D • 45°C/W)
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 3: This IC includes overtemperature protection that is intended to
protect the device during momentary overload conditions. The maximum
rated junction temperature will be exceeded when this protection is active.
Continuous operation above the specified absolute maximum operating
junction temperature may impair device reliability or permanently damage
the device.
Note 4: The linear regulator output voltage is measured with a Vishay
Siliconix Si3440DV N-channel MOSFET external pass device.
Note 5: I_CC is the sum of current into NDRV and V_CC.
Note 6: Rectifier forward voltage drop is the sum of the drop across the
rectifier diode and synchronous switch.
For more information www.linear.com/LTC3765
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