LTC3720_15 Datasheet, PDF (2/24 Pages) Linear Technology – Single Phase VRM8.5 Current Mode Step-Down Controller

LTC3720
ABSOLUTE AXI U RATI GS
(Note 1)
Input Supply Voltage
V_IN, I_ON ..................................................36V to – 0.3V
Boosted Topside Driver Supply Voltage
BOOST .................................................. 42V to – 0.3V
SW, SENSE⁺ Voltages ................................. 36V to – 5V
EXTV_CC, (BOOST – SW), RUN/SS, V_CC
VID0-VID4, PGOOD Voltages ..................... 7V to – 0.3V
FCB, V_ON, V_RNG Voltages .......... INTV_CC + 0.3V to – 0.3V
I_TH, V_FB, V_OSENSE Voltages ....................... 2.7V to – 0.3V
TG, BG, INTV_CC, EXTV_CC Peak Currents .................... 2A
TG, BG, INTV_CC, EXTV_CC RMS Currents .............. 50mA
Operating Ambient Temperature Range
LTC3720EGN (Note 2) ........................ – 40°C to 85°C
Junction Temperature (Note 3) ............................ 125°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
UW U
PACKAGE/ORDER I FOR ATIO
TOP VIEW
RUN/SS 1
V_ON 2
PGOOD 3
V_RNG 4
FCB 5
I_TH 6
SGND 7
I_ON 8
V_FB 9
SGND 10
V_FB 11
V_OSENSE 12
VID0 13
VID1 14
28 BOOST
27 TG
26 SW
25 SENSE⁺
24 SENSE^–
23 PGND
22 BG
21 INTV_CC
20 V_IN
19 EXTV_CC
18 V_CC
17 VID4
16 VID3
15 VID2
ORDER PART
NUMBER
LTC3720EGN
GN PACKAGE
28-LEAD NARROW PLASTIC SSOP
T_JMAX = 125°C, θ_JA = 95°C/ W
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS _{The q denotes specifications which apply over the full operating}
temperature range, otherwise specifications are T_A = 25°C. V_IN = 15V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX
Main Control Loop
I_Q
Input DC Supply Current
Normal
Shutdown Supply Current
900 2000
15
30
V_FB
∆V_FB(LINEREG)
∆V_FB(LOADREG)
I_FB
g_m(EA)
V_FCB
I_FCB
t_ON
Feedback Reference Voltage
Feedback Voltage Line Regulation
Feedback Voltage Load Regulation
Feedback Pin Input Current
Error Amplifier Transconductance
Forced Continuous Threshold
Forced Continuous Pin Current
On-Time
t_ON(MIN)
t_OFF(MIN)
V_SENSE(MAX)
Minimum On-Time
Minimum Off-Time
Maximum Current Sense Threshold
V_SENSE– – V_SENSE+
V_SENSE(MIN)
Minimum Current Sense Threshold
V_SENSE– – V_SENSE+
∆V_FB(OV)
V_FB(UV)
V_RUN/SS(ON)
Output Overvoltage Fault Threshold
Output Undervoltage Fault Threshold
RUN Pin Start Threshold
I_TH = 1.2V (Note 4)
V_IN = 4V to 30V, I_TH = 1.2V (Note 4)
I_TH = 0.5V to 1.9V (Note 4)
I_TH = 1.2V (Note 4)
V_FCB = 0.8V
I_ON = 60µA, V_ON = 1.5V
I_ON = 30µA, V_ON = 1.5V
I_ON = 180µA, V_ON = 0V
I_ON = 60µA, V_ON = 1.5V
V_RNG = 1V, V_FB = 0.76V
V_RNG = 0V, V_FB = 0.76V
V_RNG = INTV_CC, V_FB = 0.76V
V_RNG = 1V, V_FB = 0.84V
V_RNG = 0V, V_FB = 0.84V
V_RNG = INTV_CC, V_FB = 0.84V
q 0.792
q
1.4
q 0.76
200
425
q 113
q 79
q 158
5.5
520
q 0.8
0.800
0.002
– 0.05
–5
1.7
0.8
–1
250
500
50
250
133
93
186
– 67
– 47
– 93
7.5
600
1.5
0.808
– 0.3
±50
2
0.84
–2
300
575
100
400
153
107
214
9.5
680
2
2
UNITS
µA
µA
V
%/V
%
nA
mS
V
µA
ns
ns
ns
ns
mV
mV
mV
mV
mV
mV
%
mV
V
3720f