LTC3802_15 Datasheet, PDF (4/28 Pages) Linear Technology – Dual 550kHz Synchronous 2-Phase DC/DC Controller with Programmable Up/Down Tracking

LTC3802
ELECTRICAL CHARACTERISTICS The q denotes the specifications which apply over the full operating
temperature range. (Note 3) V_CC = PV_CC = BOOST = 5V, unless otherwise specified.
SYMBOL PARAMETER
Switcher Switching Characteristics
f_OSC
Oscillator Frequency
R_PLLIN
I_PLLLPF
Phase
V_PHASEMD
DC_MIN
DC_MAX
t_ON(MIN)
t_NOV
R_DS(ON)
PLLIN Pull-Down Current Source
Phase Detector Output Current
Sourcing Capability
Sinking Capability
TG1↓ vs PLLIN↓
TG1↓ vs PLLIN↓
TG2↓ vs PLLIN↓
TG2↓ vs PLLIN↓
Shutdown Threshold
Floating
90° Phase Threshold
Minimum TG Duty Cycle
Maximum TG Duty Cycle
TG Minimum Pulse Width
BG Minimum Pulse Width
Driver Nonoverlap
TG High R_DS(ON)
TG Low R_DS(ON)
BG High R_DS(ON)
BG Low R_DS(ON)
CONDITIONS
PLLIN Open or V_PLLIN = 0V
V_PLLLPF = 1.2V
V_PLLLPF = 0V
V_PLLLPF = 2.4V
f_PLLIN > f_OSC
f_PLLIN < f_OSC
PHASEMD Floats
V_PHASEMD = 5V
PHASEMD Floats
V_PHASEMD = 5V
V_PLLIN = 0V
V_PLLIN = 0V, V_CMPIN = 0.6V (Note 9)
(Notes 7, 10)
V_CMPIN = 0V (Note 9)
No Load
I_OUT = 100mA (Note 7)
MIN TYP MAX UNITS
490 550 610
kHz
550
kHz
250 330 400
kHz
650 750 850
kHz
5
µA
–15
µA
15
µA
0
Deg
90
Deg
180
Deg
270
Deg
q 1.2
1.7
V
2.0
V
q 3.5
4.0
4.5
V
q
0
%
q 86
89
92
%
50
ns
400
ns
10
30
80
ns
1.6 2.20
Ω
1.3 1.80
Ω
1.8 2.50
Ω
0.7 1.00
Ω
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: The LTC3802 is guaranteed to meet performance specifications
from 0°C to 70°C. Specifications over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls.
Note 3: All currents into device pins are positive; all currents out of device
pins are negative. All voltages are referenced to ground unless otherwise
specified.
Note 4: To ensure proper operation, PV_CC and BV_CC (V_BOOST – V_SW) must
be greater than V_GS(ON) of the external MOSFETs.
Note 5: Supply current in normal operation is dominated by the current
needed to charge and discharge the external MOSFET gates. This current
will vary with supply voltage and the external MOSFETs used.
Note 6: Supply current in shutdown is dominated by external MOSFET
leakage and may be significantly higher than the quiescent current drawn
by the LTC3802, especially at elevated temperature.
Note 7: Guaranteed by design, not subject to test.
Note 8: Rise and fall times are measured using 10% and 90% levels. Delay
and nonoverlap times are measured using 50% levels.
Note 9: If V_CMPIN is less than 90% of its nominal value, BG minimum
pulse width is limited to 400ns.
Note 10: The LTC3802 leading edge modulation architecture does not
have a minimum TG pulse width requirement. The TG minimum pulse
width is limited by the rise and fall times.
3802f
4