LTC3736-2 Datasheet, PDF (3/28 Pages) Linear Technology – Dual 2-Phase, No RSENSE Synchronous Controller with Output Tracking

LTC3736-2
ELECTRICAL CHARACTERISTICS _{The ● denotes specifications that apply over the full operating temperature}
range, otherwise specifications are at T_A = 25°C. V_IN = 4.2V unless otherwise specified.
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Shutdown Threshold at RUN/SS
0.45 0.65 0.85
V
Start-Up Current Source
RUN/SS = 0V
0.4
0.7
1
µA
Regulated Feedback Voltage
0°C to 85°C (Note 5)
–40°C to 85°C
0.594 0.6 0.606
V
● 0.591 0.6 0.609
V
Output Voltage Line Regulation
Output Voltage Load Regulation
V_FB1,2 Input Current
TRACK Input Current
2.75V < V_IN < 9.8V (Note 5)
I_TH = 0.9V (Note 5)
I_TH = 1.7V
(Note 5)
TRACK = 0.6V
0.05
0.2
0.12
0.5
–0.12 –0.5
10
50
10
50
mV/V
%
%
nA
nA
Overvoltage Protect Threshold
Overvoltage Protect Hysteresis
Measured at V_FB
0.66 0.68
0.7
V
20
mV
Auxiliary Feedback Threshold
SYNC/FCB Ramping Positive
0.525 0.6 0.675
V
Top Gate (TG) Drive 1, 2 Rise Time
Top Gate (TG) Drive 1, 2 Fall Time
Bottom Gate (BG) Drive 1, 2 Rise Time
Bottom Gate (BG) Drive 1, 2 Fall Time
Maximum Current Sense Voltage (∆V_SENSE(MAX))
(SENSE⁺ – SW)
Soft-Start Time
Oscillator and Phase-Locked Loop
C_L = 3000pF
C_L = 3000pF
C_L = 3000pF
C_L = 3000pF
IPRG = Floating
IPRG = 0V
IPRG = V_IN
Time for V_FB1 to Ramp from 0.05V to 0.55V
40
ns
40
ns
50
ns
40
ns
● 220
240
260
mV
● 150
167
185
mV
● 320
345
370
mV
0.667 0.833
1
ms
Oscillator Frequency
Phase-Locked Loop Lock Range
Unsynchronized (SYNC/FCB Not Clocked)
PLLLPF = Floating
PLLLPF = 0V
PLLLPF = V_IN
SYNC/FCB Clocked
Minimum Synchronizable Frequency
Maximum Synchronizable Frequency
480 550 600
kHz
260 300 340
kHz
650 750 825
kHz
●
200 250
kHz
● 850 1150
kHz
Phase Detector Output Current
Sinking
Sourcing
PGOOD Output
f_OSC > f_SYNC/FCB
f_OSC < f_SYNC/FCB
–4
µA
4
µA
PGOOD Voltage Low
PGOOD Trip Level
I_PGOOD Sinking 1mA
V_FB with Respect to Set Output Voltage
V_FB < 0.6V, Ramping Positive
V_FB < 0.6V, Ramping Negative
V_FB > 0.6V, Ramping Negative
V_FB > 0.6V, Ramping Positive
125
mV
–13 –10.0 –7
%
–16 –13.3 –10
%
7
10.0
13
%
10
13.3
16
%
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: The LTC3736E-2 is guaranteed to meet specified performance
from 0°C to 85°C. Specifications over the –40°C to 85°C operating range
are assured by design, characterization and correlation with statistical
process controls.
Note 3: 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 • θ_JA°C/W)
Note 4: Dynamic supply current is higher due to gate charge being
delivered at the switching frequency.
Note 5: The LTC3736-2 is tested in a feedback loop that servos I_TH to a
specified voltage and measures the resultant V_FB voltage.
Note 6: Peak current sense voltage is reduced dependent on duty cycle to
a percentage of value as shown in Figure 1.
37362fa
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