LTC3855EFE#PBF Linear Technology, LTC3855EFE#PBF Datasheet - Page 3

• Manufacturer Part Number: LTC3855EFE#PBF
• Description: IC BUCK SYNC ADJ 25A DL 38TSSOP
• Manufacturer: Linear Technology
• Series: PolyPhase®r
• Type: Step-Down (Buck)r

Specifications of LTC3855EFE#PBF

• Internal Switch(s): No
• Synchronous Rectifier: Yes
• Number Of Outputs: 2
• Voltage - Output: 0.6 ~ 3.3 V, 0.6 ~ 12.5 V
• Current - Output: 25A
• Frequency - Switching: 250kHz ~ 770kHz
• Voltage - Input: 4.5 ~ 38 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 38-TSSOP Exposed Pad, 38-eTSSOP, 38-HTSSOP
• Primary Input Voltage: 38V
• No. Of Outputs: 2
• Output Voltage: 12.5V
• No. Of Pins: 38
• Operating Temperature Range: -40°C To +85°C
• Msl: MSL 1 - Unlimited
• Switching Frequency Max: 770kHz
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -

elecTrical characTerisTics
orDer inForMaTion
LEAD FREE FINISH
LTC3855EFE#PBF
LTC3855IFE#PBF
LTC3855EUJ#PBF
LTC3855IUJ#PBF
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to:
For more information on tape and reel specifications, go to:
junction temperature range (E-Grade), otherwise specifications are at T
SYMBOL
Main Control Loops
V
V
V
I
V
V
g
I
DF
UVLO
UVLO
V
I
I
I
V
V
V
TG1, 2 t
TG1, 2 t
BG1, 2 t
BG1, 2 t
FB1,2
Q
SENSE1,2
TEMP1,2
TK/SS1,2
m1,2
IN
OUT
FB1,2
REFLNREG
LOADREG
OVL1,2
RUN1,2
RUN1,2HYS
SENSE(MAX)
MAX
HYS
r
f
r
f
PARAMETER
Input Voltage Range
Output Voltage Range
Regulated Feedback Voltage
Feedback Current
Reference Voltage Line Regulation
Output Voltage Load Regulation
Transconductance Amplifier g
Input DC Supply Current
Maximum Duty Factor
Undervoltage Lockout
UVLO Hysteresis
Feedback Overvoltage Lockout
Sense Pins Bias Current
DCR Tempco Compensation Current
Soft-Start Charge Current
RUN Pin ON Threshold
RUN Pin ON Hysteresis
Maximum Current Sense Threshold
TG Transition Time:
BG Transition Time:
Normal Mode
Shutdown
Rise Time
Fall Time
Rise Time
Fall Time
TAPE AND REEL
LTC3855EFE#TRPBF
LTC3855IFE#TRPBF
LTC3855EUJ#TRPBF
LTC3855IUJ#TRPBF
m
CONDITIONS
I
I
(Note 4)
V
(Note 4)
Measured in Servo Loop; ∆I
Measured in Servo Loop; ∆I
I
(Note 5)
V
V
In Dropout, f
V
Measured at V
(Each Channel); V
V
V
V
V
V
V
(Note 6)
C
C
(Note 6)
C
C
TH1,2
TH1,2
TH1,2
http://www.linear.com/leadfree/
TK/SS1,2
IN
IN
RUN1,2
INTVCC
ITEMP1,2
RUN1
FB1,2
FB1,2
FB1,2
LOAD
LOAD
LOAD
LOAD
PART MARKING*
LTC3855FE
LTC3855FE
LTC3855UJ
LTC3855UJ
= 15V
= 4.5V to 38V (Note 4)
http://www.linear.com/tapeandreel/
Voltage = 1.2V (Note 4)
Voltage = 1.2V (Note 4), T
= 1.2V; Sink/Source 5µA; (Note 4)
, V
= 0.5V, V
= 0.5V, V
= 0.5V, V
= 3300pF
= 3300pF
= 3300pF
= 3300pF
Ramping Down
= 0V
RUN2
= 0V
= 0.2V
OSC
The
Rising
FB1,2
SENSE1,2
SENSE1,2
SENSE1,2
= 500kHz
SENSE1,2
l
denotes the specifications which apply over the full operating
= 3.3V, I
= 3.3V, I
= 3.3V, I
= 3.3V
TH
TH
A
= 25°C. V
Voltage = 1.2V to 0.7V
Voltage = 1.2V to 1.6V
A
LIM
LIM
LIM
PACKAGE DESCRIPTION
38-Lead Plastic TSSOP
38-Lead Plastic TSSOP
40-Lead (6mm × 6mm) Plastic QFN
40-Lead (6mm × 6mm) Plastic QFN
= 125°C
= 0V
= Float
= INTV
IN
CC
= 15V, V
RUN1,2
l
l
l
l
l
l
l
l
l
l
l
l
l
= 5V unless otherwise noted.
0.5955
0.594
0.64
MIN
4.5
0.6
3.0
1.1
94
25
45
68
9
1
TEMPERATURE RANGE
–40°C to 85°C
–40°C to 125°C
–40°C to 85°C
–40°C to 125°C
0.600
0.600
0.002
–0.01
0.01
0.66
1.22
TYP
–15
3.5
3.2
0.6
1.2
30
95
±1
10
80
30
50
75
25
25
25
25
2
LTC3855
0.6045
0.606
MAX
12.5
0.02
–0.1
0.68
1.35
–50
0.1
3.4
1.4
38
50
±2
11
35
55
82
UNITS
mmho

3855f
%/V
mA
mV
mV
mV
mV
nA
µA
µA
µA
µA
ns
ns
ns
ns
%
%
%
V
V
V
V
V
V
V
V