LTC3718_15 Datasheet, PDF (2/20 Pages) Linear Technology – Low Input Voltage DC/DC Controller for DDR/QDR Memory Termination

LTC3718
ABSOLUTE AXI U RATI GS
(Note 1)
Input Supply Voltage (V_IN2) .......................10V to – 0.3V
Boosted Topside Driver Supply Voltage
(BOOST) ............................................... 42V to – 0.3V
V_IN1, I_ON, SW1 Voltage ............................. 36V to – 0.3V
RUN/SS, PGOOD Voltages ......................... 7V to – 0.3V
V_ON, V_REF, V_RNG Voltages .......(INTV_CC + 0.3V) to – 0.3V
I_TH, V_FB1 Voltages .................................... 2.7V to – 0.3V
SW2 Voltage ............................................. 36V to – 0.4V
V_FB2 Voltage ................................................. V_IN2 + 0.3V
SHDN Voltage ......................................................... 10V
TG, BG, INTV_CC Peak Currents .................................. 2A
TG, BG, INTV_CC RMS Currents ............................ 50mA
Operating Ambient Temperature
Range (Note 4) ................................... – 40°C to 85°C
Junction Temperature (Note 2) ............................ 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
I_TH 5
SGND1 6
I_ON 7
V_FB1 8
V_REF 9
SHDN 10
SGND2 11
V_FB2 12
24 BOOST
23 TG
22 SW1
21 SENSE⁺
20 SENSE^–
19 PGND1
18 BG
17 INTV_CC
16 V_IN1
15 V_IN2
14 PGND2
13 SW2
G PACKAGE
24-LEAD PLASTIC SSOP
T_JMAX = 125°C, θ_JA = 130°C/ W
ORDER PART
NUMBER
LTC3718EG
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_IN1 = 15V, V_IN2 = 1.5V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX
Buck Regulator
I_Q(VIN1)
V_FB1
∆V_FB1(LINE)
∆V_FB1(LOAD)
g_m(EA)
t_ON
t_ON(MIN)
t_OFF(MIN)
V_SENSE(MAX)
V_SENSE(MIN)
∆V_FB1(OV)
∆V_FB1(UV)
V_RUN/SS(ON)
V_RUN/SS(LE)
Input DC Supply Current (V_IN1)
Normal
Shutdown Supply Current
Feedback Voltage Accuracy
Feedback Voltage Line Regulation
Feedback Voltage Load Regulation
Error Amplifier Transconductance
On-Time
Minimum On-Time
Minimum Off-Time
Maximum Current Sense Threshold
V_PGND – V_SW1 (Source)
Minimum Current Sense Threshold
V_PGND – V_SW1 (Sink)
Output Overvoltage Fault Threshold
Output Undervoltage Fault Threshold
RUN Pin Start Threshold
RUN Pin Latchoff Enable
V_RUN/SS = 0V
I_TH = 1.2V (Note 3)
V_IN1 = 4V to 36V, I_TH = 1.2V (Note 3)
I_TH = 0.5V to 1.9V (Note 3)
I_TH = 1.2V (Note 3)
I_ON = 60µA, V_ON = 1.5V
I_ON = 30µA, V_ON = 1.5V
I_ON = 180µA
V_RNG = 1V, V_FB1 = V_REF/2 – 50mV
V_RNG = 0V, V_FB1 = V_REF/2 – 50mV
V_RNG = INTV_CC, V_FB1 = V_REF/2 – 50mV
V_RNG = 1V, V_FB1 = V_REF/2 + 50mV
V_RNG = 0V, V_FB1 = V_REF/2 + 50mV
V_RNG = INTV_CC, V_FB1 = V_REF/2 + 50mV
RUN/SS Pin Rising
q – 0.65
q
0.93
200
400
q 108
q 76
q 148
– 140
– 97
– 200
8
q 0.8
1000
15
0.1
0.002
– 0.05
1.13
250
500
50
300
135
95
185
– 165
– 115
– 235
10
– 25
1.5
4
2000
30
0.65
– 0.3
1.33
300
600
100
400
162
114
222
– 190
– 133
– 270
12
2
4.5
2
UNITS
µA
µA
%
%/V
%
mS
ns
ns
ns
ns
mV
mV
mV
mV
mV
mV
%
%
V
V
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