LTC3729L-6 Datasheet, PDF (4/28 Pages) Linear Technology – PolyPhase, Synchronous Step-Down Switching Regulator

LTC3729L-6
ELECTRICAL CHARACTERISTICS The q denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_IN = 15V, V_RUN/SS = 5V unless otherwise noted.
SYMBOL PARAMETER
CONDITIONS
MIN TYP MAX UNITS
R_RELPHS
CLKOUT
Controller 2-Controller 1 Phase
Phase (Relative to Controller 1)
CLK_HIGH Clock High Output Voltage
CLK_LOW Clock Low Output Voltage
PGOOD Output
V_PGL
I_PGOOD
V_PG
PGOOD Voltage Low
PGOOD Leakage Current
PGOOD Trip Level, Either Controller
t_MASK
PGOOD Mask Timer
Differential Amplifier Gain Block (Note 5)
A_DA
CMRR_DA
R_IN
Gain
Common Mode Rejection Ratio
Input Resistance
V_PHASMD = 0V, Open
V_PHASMD = 5V
V_PHASMD = 0V
V_PHASMD = Open
V_PHASMD = 5V
I_PGOOD = 2mA
V_PGOOD = 5V
V_EAIN with Respect to Set Output Voltage
V_EAIN Ramping Negative
V_EAIN Ramping Positive
0V < V_CM < 5V
Measured at V_OS+ Input
180
Deg
240
Deg
60
Deg
90
Deg
120
Deg
4
V
0.2
V
0.1
0.3
V
±1
µA
–8
– 10 – 12
%
8
10
12
%
100
µs
0.995
1
1.005
V/V
46
55
dB
80
kΩ
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: T_J is calculated from the ambient temperature T_A and power
dissipation P_D according to the following formulas:
T_J = T_A + (P_D • 34°C/W)
Note 3: The I.C. is tested in a feedback loop that servos V_ITH to a specified
voltage and measures the resultant V_EAIN.
Note 4: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications Information.
Note 5: The minimum on-time condition corresponds to the on inductor
peak-to-peak ripple current ≥ 40% of I_MAX (see Minimum On-Time
Considerations in the Applications Information section).
Note 6: The LTC3729LEUH-6 is guaranteed to meet performance
specifications from 0°C to 70°C. Specifications over the – 40°C to 85°C
operating ambient temperature range are assured by design,
characterization and correlation with statistical process controls.
TYPICAL PERFOR A CE CHARACTERISTICS
Efficiency vs Output Current
(Figure 12)
100
80
60
40
20
0
0.1
V_IN = 5V
V_IN = 8V
V_IN = 12V
V_IN = 20V
V_OUT = 3.3V
V_EXTVCC = 5V
I_OUT = 20A
T_A = 25°C
1
10
100
OUTPUT CURRENT (A)
3729L-6 G01
4
Efficiency vs Output Current
(Figure 12)
100
V_EXTVCC = 5V
90
V_EXTVCC = 0V
80
70
60
V_OUT = 3.3V
T_A = 25°C
50
1
10
100
OUTPUT CURRENT (A)
3729L-6 G02
Efficiency vs Input Voltage
(Figure 12)
100
V_OUT = 3.3V
V_EXTVCC = 5V
I_OUT = 20A
T_A = 25°C
90
80
70
5
10
V_IN (V)
15
20
3729L-6 G03
sn3729l6 3729l6fs