LTC3875_15 Datasheet, PDF (3/44 Pages) Linear Technology – Dual, 2-Phase, Synchronous Controller with Low Value DCR Sensing and Temperature Compensation

LTC3875
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_IN = 15V, V_RUN1,2 = 5V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX
V_LOADREG
Output Voltage Load Regulation
g_m1,2
Transconductance Amplifier g_m
Thermal Functions
(Note 4)
Measured in Servo Loop; ∆I_TH Voltage = 1.2V to 0.7V l
Measured in Servo Loop; ∆I_TH Voltage = 1.2V to 1.6V l
I_TH1,2 = 1.2V; Sink/Source 5µA (Note 4)
0.01 0.1
–0.01 –0.1
2.2
I_TCOMP1,2
Thermal Sensor Current
T_SHDN
Internal Thermal Shutdown
T_HYS
Internal TS Hysteresis
Fast Transient Functions
(Note 8)
(Note 8)
29 30 31
160
10
I_FAST
Fast Transient Program Current
Current Sensing Functions
I_SENSE(AC)
I_SENSE(DC)
AC Sense Pins Bias Current
DC Sense Pins Bias Current
Each Channel; V_SNSA+(S) = 3.3V
Each Channel; V_SNSD+(S) = 3.3V
A_VT(SNS)
Total Sense Gain to Current Comp
V_{SENSE(MAX)(DC)}
Maximum Current Sense Threshold 0°C to 85°C
with SNSD⁺ Pin to V_OUT
VVVVV_{SSSSSNNNNNSSSSS–––––(((((sssss)))))}
=
=
=
=
=
1.2V,
1.2V,
1.2V,
1.2V,
1.2V,
ILIM
ILIM
ILIM
ILIM
ILIM
=
=
=
=
=
0V
1/4 INTV_CC
1/2 INTV_CC
3/4 INTV_CC
INTV_CC
–40°C to 125°C
VVVVV_{SSSSSNNNNNSSSSS–––––(((((sssss)))))}
=
=
=
=
=
1.2V,
1.2V,
1.2V,
1.2V,
1.2V,
ILIM
ILIM
ILIM
ILIM
ILIM
=
=
=
=
=
0V
1/4 INTV_CC
1/2 INTV_CC
3/4 INTV_CC
INTV_CC
V_{SENSE(MAX)(NODE)}
Maximum Current Sense Threshold
with SNSD⁺ Pin to GND
VVVVV^{SSSSSNNNNNSSSSS–––––(((((sssss)))))}
=
=
=
=
=
1.2V,
1.2V,
1.2V,
1.2V,
1.2V,
ILIM
ILIM
ILIM
ILIM
ILIM
=
=
=
=
=
0V
1/4 INTV_CC
1/2 INTV_CC
3/4 INTV_CC
INTV_CC
I_MISMATCH
Channel-to-Channel Current
Mismatch
ILIM = Float, ENTMPB = Float
(Thermal Balance Disabled)
l9
10 11
l
±0.5 ±2
l
±30 ±50
5
9
10 11
14 15 16
19 20 21
23.5 25 26.5
28.5 30 31.5
l 8.5 10 11.5
l 13.5 15 16.5
l 17.5 20 22.5
l 22 25 28
l 26.5 30 33.5
l 45 50 55
l 70 75 80
l 95 100 105
l 117.5 125 132.5
l 142.5 150 157.5
5
I_Q
UVLO
UVLO Hyst
V_OVL
I_TK/SS1,2
V_RUN1,2
V_RUN1,2HYS
Driver Functions
Input DC Supply Current
Normal Mode
Shutdown
Undervoltage Lockout
UVLO Hysteresis
Feedback Overvoltage Lockout
Soft-Start Charge Current
RUN Pin On Threshold
RUN Pin On Hysteresis
(Note 5)
V_IN = 15V (without EXTV_CC Enabled)
V_RUN1,2 = 0V
V_INTVCC Ramping Down
Measured at V_OSNS1,2+
V_TK/SS1,2 = 0V
V_RUN1, V_RUN2 Rising
7
10
40 60
3.5 3.7 4.0
0.5
l 0.625 0.645 0.665
l 1.0 1.25 1.5
l 1.1 1.22 1.35
80
TG Transition Time
(Note 6)
TG1,2 t_r
Rise Time
C_LOAD = 3300pF
25
TG1,2 t_f
Fall Time
C_LOAD = 3300pF
25
BG Transition Time
(Note 6)
BG1,2 t_r
Rise Time
C_LOAD = 3300pF
25
BG1,2 t_f
Fall Time
C_LOAD = 3300pF
25
UNITS
%
%
mmho
µA
°C
°C
µA
µA
nA
V/V
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
%
mA
µA
V
V
V
µA
V
mV
ns
ns
ns
ns
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