LTC3548A Datasheet, PDF (3/20 Pages) Linear Technology – Dual Synchronous 400mA/800mA, 2.25MHz Step-Down DC/DC Regulator

LTC3548A
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, unless otherwise specified. (Note 2)
SYMBOL
V_IN
I_FB
V_FB
ΔV_{LINE REG}
ΔV_{LOAD REG}
I_S
f_OSC
f_SYNC
I_LIM
R_DS(ON)
I_SW(LKG)
POR
PARAMETER
CONDITIONS
Operating Voltage Range
●
Feedback Pin Input Current
●
Feedback Voltage (Note 3)
0°C ≤ T_A ≤ 85°C
–40°C ≤ T_A ≤ 125°C (Note 2)
●
Reference Voltage Line Regulation V_IN = 2.5V to 5.5V (Note 3)
Output Voltage Load Regulation
MODE/SYNC = 0V (Note 3)
Input DC Supply Current
Active Mode
Sleep Mode
Shutdown
Oscillator Frequency
Synchronization Frequency
(Note 4)
V_FB1 = V_FB2 = 0.5V
V_FB1 = V_FB2 = 0.63V, MODE/SYNC = 3.6V
RUN = 0V, V_IN = 5.5V, MODE/SYNC = 0V
V_FBX = 0.6V
●
Peak Switch Current Limit Channel 1
Peak Switch Current Limit Channel 2
Top Switch On-Resistance
Bottom Switch On-Resistance
V_IN = 3V, V_FBX = 0.5V, Duty Cycle < 35%
V_IN = 3V, V_FBX = 0.5V, Duty Cycle < 35%
(Note 6)
(Note 6)
Switch Leakage Current
Power-On Reset Threshold
Power-On Reset On-Resistance
V_IN = 5V, V_RUN = 0V, V_FBX = 0V
V_FBX Ramping Up, MODE/SYNC = 0V
V_FBX Ramping Down, MODE/SYNC = 0V
MIN
2.5
0.588
0.585
1.8
1
0.6
TYP MAX
5.5
30
0.6 0.612
0.6 0.612
0.3
0.5
0.5
700 950
40
60
0.1
1
2.25
2.7
2.25
1.2
1.6
0.7
0.9
0.35 0.45
0.30 0.45
0.01
1
8.5
–8.5
100 200
UNITS
V
nA
V
V
%/V
%
μA
μA
μA
MHz
MHz
A
A
Ω
Ω
μA
%
%
Ω
V_RUN
I_RUN
V_MODE
Power-On Reset Delay
RUN/SS Threshold Low
RUN/SS Threshold High
RUN/SS Leakage Current
MODE Threshold Low
MODE Threshold High
65,536
●
0.3
●
1
1.5
2
●
0.01
1
0
0.5
V_IN – 0.5
V_IN
Cycles
V
V
μA
V
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: The LTC3548AE is guaranteed to meet specified performance from
0°C to 85°C. Specifications over the –40°C and 85°C operating junction
temperature range are assured by design, characterization and correlation
with statistical process controls. The LTC3548AI is guaranteed over the full
–40°C to 125°C operating junction temperature range.
Note 3: The LTC3548A is tested in a proprietary test mode that connects
V_FB to the output of the error amplifier.
Note 4: Dynamic supply current is higher due to the internal gate charge
being delivered at the switching frequency.
Note 5: T_J is calculated from the ambient, T_A, and power dissipation, P_D,
according to the following formula:
T_J = T_A + (P_D • θ_JA).
Note 6: The DFN switch on-resistance is guaranteed by correlation to
wafer level measurements.
3548af
3