Datasheet

LTC3773
3
3773fb
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Main Control Loop
V
FB
Feedback Voltage V
ITH
= 1.2V, 0°C ≤ T ≤ 85°C (Note 4)
●
0.594
0.591
0.600
0.600
0.606
0.609
V
V
I
VFB
Feedback Pin Input Current 0 ≤ V
FB
≤ 1V –15 –100 nA
V
SENSEMAX
Maximum Current Sense Threshold V
FB
= 0.55V, V
TRACK
= 1V, V
SENSE
–
= 2.5V
●
65
60
75
75
85
90
mV
mV
V
FBLOADREG
Feedback Voltage Load Regulation Measured in Servo Loop (Note 4)
Δ
ITH
Voltage = 1.2V to 0.7V
Δ
ITH
Voltage = 1.2V to 2V
●
●
0.15
–0.2
0.5
–0.5
%
%
V
FBLNREG
Feedback Voltage Line Regulation V
CC
= 4.5V to 6V 0.01 %/V
g
m
Transconductance Amplifi er g
m
V
ITH
= 1.2V, Sink/Source 25μA (Note 4)
●
2.3 2.7 3.2 mmho
f
u
Transconductance Amplifi er GBW V
ITH
= 1.2V (Note 5) 3 MHz
A
ERR
Transconductance Amplifi er DC Gain V
ITH
= 0.8V to 1.6V
●
50 56 dB
V
UVR
V
CC
Undervoltage Reset
Undervoltage Hysteresis
V
CC
Ramping Positive 3.7 4.1
0.16
4.4 V
V
V
CC
V
CC
Supply Voltage
●
4.5 5 6 V
I
VCC
V
CC
Supply Current
Normal Mode
Shutdown
V
CC
= 5V
V
SDB
= 0V
2.8
20
4
30
mA
μA
I
VDR
V
DR
Supply Current
Normal Mode
Shutdown
V
DR
= 5V (Note 6)
V
SDB
= 0V
5
1
mA
μA
I
BOOST
V
BOOST
Supply Current
Normal Mode
Shutdown
V
BOOST
= 5V, V
SW
= 0V (Note 6)
V
SDB
= 0V
1
1
mA
μA
I
SDB
SDB Source Current
SDB1, SDB2, SDB3 Source Content
–1.5
–0.5
μA
μA
V
SDB
SDB Power Up Threshold
SDB1 Pin CH1 ON Threshold
SDB2 Pin CH2 ON Threshold
SDB3 Pin CH3 ON Threshold
Ramping Positive
●
●
●
●
0.4
1.14
1.71
2.3
1.2
1.8
2.4
1.26
1.89
2.5
V
V
V
V
Channel On Threshold Hysteresis –10 %
I
SENSE
SENSE Pins Source Current V
SENSE
+
, V
SENSE
–
= 1.2V, Current at Each Pin –13 –20 μA
DF
MAX
Maximum Duty Factor PLLFLTR Floats, In Dropout 97 98.5 %
TG R
UP
TG Driver Pull-Up On-Resistance TG High, I
OUT
= 100mA (Note 7) 2.2 Ω
TG R
DOWN
TG Driver Pull-Down On-Resistance TG Low, I
OUT
= 100mA (Note 7) 1.8 Ω
BG R
UP
BG Driver Pull-Up On-Resistance BG High, I
OUT
= 100mA (Note 7) 2.4
Ω
BG R
DOWN
BG Driver Pull-Down On-Resistance BG Low, I
OUT
= 100mA (Note 7) 0.9 Ω
TG/BG t
1D
Top Gate OFF to Bottom Gate ON Delay
Synchronous Switch-On Delay Time
All Controllers 50 ns
BG/TG t
2D
Bottom Gate OFF to Top Gate ON Delay
Top Switch-On Delay Time
All Controllers 50 ns
t
ON(MIN)
Minimum On-Time Tested with a Square Wave (Note 8) 130 ns
Tracking
I
TRACK
TRACK Pin Pull-Up Current V
SDB
= 5V, V
TRACK
= 0V –1 μA
V
FBTRACK
V
FB
Voltage During Tracking V
TRACK
= 0.2V, V
ITH
= 1.2V (Note 4)
V
TRACK
= 0.4V, V
ITH
= 1.2V (Note 4)
180
380
200
400
220
420
mV
mV
ELECTRICAL CHARACTERISTICS
(Note 3) The ● denotes the specifi cations which apply over the full
operating temperature range, otherwise specifi cations are at T
A
= 25°C. V
CC
= V
DR
= V
BOOST
= V
SDB
= 5V, unless otherwise noted.