LTC3728LEGN-1#PBF Linear Technology, LTC3728LEGN-1#PBF Datasheet - Page 3
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LTC3728LEGN-1#PBF
Manufacturer Part Number
LTC3728LEGN-1#PBF
Description
IC REG SYNC DUAL 28-SSOP
Manufacturer
Linear Technology
Series
PolyPhase®r
Type
Step-Down (Buck)r
Datasheet
1.LTC3728LEGN-1PBF.pdf
(32 pages)
Specifications of LTC3728LEGN-1#PBF
Internal Switch(s)
No
Synchronous Rectifier
Yes
Number Of Outputs
2
Voltage - Output
0.8 ~ 7 V
Current - Output
3A
Frequency - Switching
250kHz ~ 550kHz
Voltage - Input
4.5 ~ 28 V
Operating Temperature
-40°C ~ 85°C
Mounting Type
Surface Mount
Package / Case
28-SSOP
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Power - Output
-
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
ELECTRICAL CHARACTERISTICS
temperature range, otherwise specifi cations are at T
SYMBOL
Main Control Loops
V
I
V
V
g
g
I
V
I
V
UVLO
V
I
DF
I
V
V
TG1, 2 t
TG1, 2 t
BG1, 2 t
BG1, 2 t
TG/BG t
BG/TG t
t
INTV
V
V
V
V
V
Oscillator and Phase-Locked Loop
f
f
f
R
VOSENSE1, 2
Q
FCB
SENSE
RUN/SS1, 2
ON(MIN)
NOM
LOW
HIGH
m1, 2
mGBW1, 2
OSENSE1, 2
REFLNREG
LOADREG
FCB
BINHIBIT
OVL
RUN/SS1, 2
SENSE(MAX)
INTVCC
LDO
LDO
EXTVCC
LDOHYS
PLLIN
MAX
CC
INT
EXT
Linear Regulator
1D
2D
r
f
r
f
ON RUN/SS Pin ON Threshold
PARAMETER
Regulated Feedback Voltage
Feedback Current
Reference Voltage Line Regulation
Output Voltage Load Regulation
Transconductance Amplifi er g
Transconductance Amplifi er GBW
Input DC Supply Current
Forced Continuous Threshold
Forced Continuous Pin Current
Burst Inhibit (Constant Frequency)
Threshold
Undervoltage Lockout
Feedback Overvoltage Lockout
Sense Pins Total Source Current
Maximum Duty Factor
Soft-Start Charge Current
Maximum Current Sense Threshold
TG Transition Time:
Rise Time
Fall Time
BG Transition Time:
Rise Time
Fall Time
Top Gate Off to Bottom Gate On Delay
Synchronous Switch-On Delay Time
Bottom Gate Off to Top Gate On Delay
Top Switch-On Delay Time
Minimum On-Time
Internal V
INTV
EXTV
EXTV
EXTV
Nominal Frequency
Lowest Frequency
Highest Frequency
PLLIN Input Resistance
Normal Mode
Shutdown
CC
CC
CC
CC
Load Regulation
Voltage Drop
Switchover Voltage
Hysteresis
CC
Voltage
m
CONDITIONS
(Note 3); I
(Note 3)
V
(Note 3)
Measured in Servo Loop; ΔI
Measured in Servo Loop; ΔI
I
I
(Note 4)
V
V
V
Measured at FCB pin
V
Measured at V
(Each Channel); V
In Dropout
V
V
V
V
(Note 5)
C
C
(Note 5)
C
C
C
C
Tested with a Square Wave (Note 6)
6V < V
I
I
I
V
V
V
TH1, 2
TH1, 2
CC
CC
CC
IN
IN
RUN/SS1, 2
FCB
IN
RUN/SS1, 2
RUN/SS1,
OSENSE1, 2
OSENSE1, 2
LOAD
LOAD
LOAD
LOAD
LOAD
LOAD
PLLFLTR
PLLFLTR
PLLFLTR
A
= 0 to 20mA, V
= 20mA, V
= 20mA, EXTV
= 15V; EXTV
Ramping Down
= 25°C. V
= 3.6V to 30V (Note 3)
= 0.85V
= 1.2V; Sink/Source 5μA; (Note 3)
= 1.2V; (Note 3)
= 3300pF
= 3300pF
= 3300pF
= 3300pF
= 3300pF Each Driver
= 3300pF Each Driver
IN
< 30V, V
= 1.2V
= 0V
≥ 2.4V
The
V
TH1, 2
= 0V
RUN/SS2
= 0.7V,V
= 0.7V,V
= 1.9V
EXTVCC
OSENSE1, 2
l
IN
CC
Voltage = 1.2V
denotes the specifi cations which apply over the full operating
EXTVCC
= 15V, V
SENSE1
CC
EXTVCC
Tied to V
Rising
SENSE1 – , 2 –
SENSE1 – , 2 –
Ramping Positive
= 5V
–
= 4V
, 2
= 4V
RUN/SS1, 2
– = V
OUT1
TH
TH
Voltage = 1.2V to 0.7V
Voltage = 1.2V to 2.0V
= 5V
= 5V
; V
SENSE1
OUT1
= 5V unless otherwise noted.
+
= 5V
, 2
+ = 0V
●
●
●
●
●
●
●
●
0.788
– 0.50
MIN
0.76
0.84
–90
360
230
480
0.5
1.0
4.8
4.5
98
65
62
LTC3728L-1
0.800
0.002
0.800
–0.18
– 0.1
0.86
99.4
TYP
450
–60
100
100
400
260
550
0.1
1.3
4.3
3.5
1.2
1.5
5.0
0.2
4.7
0.2
– 5
20
75
75
55
55
45
45
80
80
50
3
0.812
MAX
0.02
–0.5
0.84
–0.1
0.88
–50
100
100
100
200
440
290
590
0.5
4.8
2.0
5.2
2.0
35
85
88
90
4
3728l1fc
UNITS
mmho
3
MHz
%/V
kHz
kHz
kHz
mV
mV
mV
kΩ
nA
μA
μA
μA
μA
μA
ns
ns
ns
ns
ns
ns
ns
%
%
%
%
V
V
V
V
V
V
V
V
V