LTC3861-1 Datasheet, PDF (4/36 Pages) Linear Technology – Dual, Multiphase Step-Down Voltage Mode DC/DC Controller with Accurate Current Sharing

LTC3861-1
Electrical Characteristics The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T_J = 25°C (Note 3). V_CC = 5V, V_RUN1,2 = 5V, V_FREQ = 5V, V_CLKIN = 0V,
V_FB = 0.6V, f_OSC = 0.6MHz, unless otherwise specified.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
I_ISENSE
SENSE Pin Input Current
V_OS
Current Sense Input Referred Offset
Oscillator and Phase-Locked Loop
V_CM = 1.5V
–40°C to 125°C
100
nA
l –1.25
1.25
mV
f_OSC
Oscillator Frequency
V_CLKIN = 0V
V_FREQ = 0V
V_FREQ = 5V
V_CLKIN = 5V
R_FREQ < 24.9k
R_FREQ = 36.5k
R_FREQ = 48.7k
R_FREQ = 64.9k
R_FREQ = 88.7k
Maximum Frequency
Minimum Frequency
l 360
400
440
kHz
l 540
600
660
kHz
200
kHz
600
kHz
1
MHz
1.45
MHz
2.1
MHz
3
MHz
0.25
MHz
I_FREQ
t_CLKIN(HI)
t_CLKIN(LO)
R_CLKIN
V_CLKIN
V_FREQ
FREQ Pin Output Current
CLKIN Pulse Width High
CLKIN Pulse Width Low
CLKIN Pull-Up Resistance
CLKIN Input Threshold
FREQ Input Threshold
V_OL(CLKOUT)
V_OH(CLKOUT)
θ₂-θ₁
CLKOUT Low Output Voltage
CLKOUT High Output Voltage
Channel 1-to-Channel 2 Phase Relationship
θ_CLKOUT-θ₁
CLKOUT-to-Channel 1 Phase Relationship
PWM/PWMEN Outputs
V_FREQ = 0.8V
V_CLKIN = 0V to 5V
V_CLKIN = 0V to 5V
V_CLKIN Falling
V_CLKIN Rising
V_CLKIN = 0V
V_FREQ Falling
V_FREQ Rising
I_LOAD = –500µA
I_LOAD = 500µA
V_PHSMD = 0V
V_PHSMD = Float
V_PHSMD = V_CC
V_PHSMD = 0V
V_PHSMD = Float
V_PHSMD = V_CC
18.5
20
21.5
µA
100
ns
100
ns
13
kΩ
1.2
V
2
V
1.5
V
2.5
V
0.2
V
V_CC – 0.2
V
180
Deg
180
Deg
120
Deg
60
Deg
90
Deg
240
Deg
PWM
PWM Output High Voltage
PWM Output Low Voltage
PWM Output Current in Hi-Z State
I_LOAD = 500µA
I_LOAD = –500µA
l 4.5
l
V
0.5
V
±5
µA
PWM Maximum Duty Cycle
91.5
%
PWMEN
PWMEN Output High Voltage
I_LOAD = 1mA
l 4.5
V
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: T_J is calculated from the ambient temperature T_A and power
dissipation P_D according to the following formula:
T_J = T_A + (P_D • 34°C/W)
Note 3: The LTC3861-1 is tested under pulsed load conditions such that
T_J ≈ T_A. The LTC3861-1E is guaranteed to meet performance
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 LTC3861-1I is guaranteed over the full –40°C to 125°C
operating junction temperature range. The maximum ambient temperature
consistent with these specifications is determined by specific operating
conditions in conjunction with board layout, the rated package thermal
resistors and other environmental factors.
Note 4: Guaranteed by design.
38611f
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