Datasheet

LTC3675/LTC3675-1
4
36751fc
For more information www.linear.com/LTC3675
elecTrical characTerisTics
The l denotes the specifications which apply over the full operating
junction temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 3.6V. (Note 2)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
IN
Input Supply Range
l
2.7 5.5 V
V
IN_FALLING
Falling Undervoltage Threshold
l
2.35 2.45 2.55 V
V
IN_RISING
Rising Undervoltage Threshold
l
2.45 2.55 2.65 V
V
IN_WARN
Falling Undervoltage Warning Threshold UV[2], UV[1], UV[0] = 000 2.7 V
UV[2], UV[1], UV[0] = 001 2.8 V
UV[2], UV[1], UV[0] = 010 2.9 V
UV[2], UV[1], UV[0] = 011 3.0 V
UV[2], UV[1], UV[0] = 100 3.1 V
UV[2], UV[1], UV[0] = 101 3.2 V
UV[2], UV[1], UV[0] = 110 3.3 V
UV[2], UV[1], UV[0] = 111 3.4 V
V
IN_HYS
V
IN
Undervoltage Warning Hysteresis 50 mV
V
IN_WARN(LSB)
Undervoltage Warning Threshold Step Size
l
85 100 115 mV
OT Overtemperature Shutdown 150 °C
OT_WARN Overtemperature Warning Threshold; Die
Temperature Below OT that Causes IRQB = 0
OT[1], OT[0] = 00
OT[1], OT[0] = 01
OT[1], OT[0] = 10
OT[1], OT[0] = 11
10
20
30
40
°C
°C
°C
°C
I
VIN_ALLOFF
Input Supply Current All Switching Regulators and LED Driver
in Shutdown, ONB = HIGH; Sum of All V
IN
Currents
16 28 µA
f
OSC
Voltage Regulator Switching Frequency All Voltage Regulators
l
1.8 2.25 2.7 MHz
V
PGOOD(FALL)
Falling PGOOD Threshold Voltage Full-Scale (1,1,1,1) Reference Voltage
l
88 92 96 %
V
PGOOD(HYS)
PGOOD Hysteresis All Regulators Except LED Driver 1 %
1A Buck Regulator (Buck Regulators 1 and 2)
I
VIN1,2
Pulse-Skipping Input Current
Burst Mode
®
Operation Input Current
V
FB1
= V
FB2
= 0.85V (Notes 4, 5)
V
FB1
= V
FB2
= 0.85V (Notes 4, 5)
105
20
200
50
µA
µA
I
FWD1,2
PMOS Current Limit (Note 6) 2.25 2.8 3.35 A
V
FB1,2(HIGH)
Feedback Regulation Voltage Pulse-Skipping Mode Full-Scale (1,1,1,1)
l
780 800 820 mV
V
FB1,2(LOW)
Feedback Regulation Voltage Pulse-Skipping Mode Full-Scale (0,0,0,0)
l
405 425 445 mV
V
LSB1,2
FB1, FB2 Regulation Voltage Step Size 25 mV
I
FB12
Feedback Leakage Current V
FB1
= V
FB2
= 0.85V –50 50 nA
D
MAX1,2
Maximum Duty Cycle V
FB1
= V
FB2
= 0V
l
100 %
R
PMOS1,2
PMOS On-Resistance I
SW1
= I
SW2
= 100mA 265 mΩ
R
NMOS1,2
NMOS On-Resistance I
SW1
= I
SW2
= –100mA 280 mΩ
I
LEAKP1,2
PMOS Leakage Current EN1 = EN2 = 0 –2 2 µA
I
LEAKN1,2
NMOS Leakage Current EN1 = EN2 = 0 –2 2 µA
R
SWPD1,2
Output Pull-Down Resistance in Shutdown EN1 = EN2 = 0 (I
2
C Bit Set) 10 kΩ
t
SS1,2
Soft-Start Time 500 µs
500mA Buck Regulator (Buck Regulators 3 and 4)
I
VIN3,4
Pulse-Skipping Input Current
Burst Mode Operation Input Current
V
FB3
= V
FB4
= 0.85V (Notes 4, 5)
V
FB3
= V
FB4
= 0.85V (Notes 4, 5)
105
20
200
50
µA
µA
I
FWD3,4
PMOS Current Limit (Note 6) 0.75 1.2 1.65 A