EXPOSED PAD (PIN 11) IS GND, MUST BE CONNECTED TO GND
MSE PACKAGE
10-LEAD PLASTIC MSOP
T
JMAX
= 150°C,
θ
JA
= 45°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE CONNECTED TO GND
orDer inForMation
LEAD FREE FINISH
LTC3805EDD#PBF
LTC3805IDD#PBF
LTC3805EMSE#PBF
LTC3805IMSE#PBF
LTC3805HMSE#PBF
LTC3805MPMSE#PBF
LEAD BASED FINISH
LTC3805EDD
LTC3805IDD
LTC3805EMSE
LTC3805IMSE
LTC3805HMSE
LTC3805MPMSE
TAPE AND REEL
LTC3805EDD#TRPBF
LTC3805IDD#TRPBF
LTC3805EMSE#TRPBF
LTC3805IMSE#TRPBF
LTC3805HMSE#TRPBF
LTC3805MPMSE#TRPBF
TAPE AND REEL
LTC3805EDD#TR
LTC3805IDD#TR
LTC3805EMSE#TR
LTC3805IMSE#TR
LTC3805HMSE#TR
LTC3805MPMSE#TR
PART MARKING*
LCJM
LCJM
LTCJK
LTCJK
LTCJK
LTCJK
PART MARKING*
LCJM
LCJM
LTCJK
LTCJK
LTCJK
LTCJK
PACKAGE DESCRIPTION
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
PACKAGE DESCRIPTION
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
TEMPERATURE RANGE
–40°C to 85°C
–40°C to 125°C
–40°C to 85°C
–40°C to 125°C
–40°C to 150°C
–55°C to 150°C
TEMPERATURE RANGE
–40°C to 85°C
–40°C to 125°C
–40°C to 85°C
–40°C to 125°C
–40°C to 150°C
–55°C to 150°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
3805fg
2
LTC3805
electrical characteristics
SYMBOL
V
TURNON
V
TURNOFF
V
HYST
V
CLAMP1mA
V
CLAMP25mA
I
CC
PARAMETER
V
CC
Turn-On Voltage
V
CC
Turn-Off Voltage
V
CC
Hysteresis
V
CC
Shunt Regulator Voltage
V
CC
Shunt Regulator Voltage
Input DC Supply Current
V
CC
Sinking 1mA, V
RUN
= 0
V
CC
Sinking 25mA, V
RUN
= 0
Normal Operation (f
OSC
= 200kHz)
(Note 4)
V
RUN
< V
RUNON
or V
CC
< V
TURNON
– 100mV
(Micropower Start-Up)
V
RUNON
V
RUNOFF
I
RUN(HYST)
V
FB
RUN Turn-On Voltage
RUN Turn-Off Voltage
RUN Hysteresis Current
Regulated Feedback Voltage
0°C ≤ T
J
≤ 85°C (E-Grade) (Note 5)
–40°C ≤ T
J
≤ 85°C (E-Grade) (Note 5)
–40°C ≤ T
J
≤ 125°C (I-Grade) (Note 5)
–40°C ≤ T
J
≤ 150°C (H-Grade) (Note 5)
–55°C ≤ T
J
≤ 150°C (MP-Grade)
V
ITH
= 1.3V (Note 5)
I
TH
Pin Load = ±5µA (Note 5)
V
TURNOFF
< V
CC
< V
CLAMP1mA
(Note 5)
I
TH
Sinking 5µA (Note 5)
I
TH
Sourcing 5µA (Note 5)
R
FS
= 350k
R
FS
= 36k
DC
ON(MIN)
DC
ON(MAX)
f
SYNC
V
SYNC
I
SS
I
FTO
t
SS(INT)
t
FTO(INT)
t
RISE
t
FALL
V
I(MAX)
I
SL(MAX)
V
OCT
I
OC
Minimum Switch-On Duty Cycle
Maximum Switch-On Duty Cycle
As a Function of f
OSC
Minimum SYNC Amplitude
Soft-Start Current
Fault Timeout Current
Internal Soft-Start Time
Internal Fault Timeout
Gate Drive Rise Time
Gate Drive Fall Time
Peak Current Sense Voltage
Peak Slope Compensation Output
Current
Overcurrent Threshold
Overcurrent Threshold Adjust Current
No External Capacitor on SSFLT
No External Capacitor on SSFLT
C
LOAD
= 3000pF
C
LOAD
= 3000pF
R
SL
= 0 (Note 6)
(Note 7)
R
OC
= 0 (Note 8)
l
l
l
l
l
l
l
l
l
l
l
l
The
l
denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C, V
CC
= 8V, unless otherwise noted (Note 2).
CONDITIONS
l
l
MIN
7.75
3.75
8.8
8.9
TYP
8.4
3.95
4.5
9.25
9.5
360
40
MAX
9
4.15
9.65
9.9
UNITS
V
V
V
V
V
µA
90
1.292
1.248
5.8
0.812
0.812
0.812
0.820
0.820
µA
V
V
µA
V
V
V
V
V
nA
µA/V
mV/V
mV/µA
mV/µA
kHz
kHz
V
CC
Sinking 1mA
V
CC
Sinking 1mA
1.122
1.092
4
0.788
0.780
0.780
0.770
0.770
1.207
1.170
5
0.800
0.800
0.800
0.800
0.800
20
333
0.05
3
3
70
700
6
I
FB
g
m
∆V
O(LINE)
∆V
O(LOAD)
f
OSC
V
FB
Input Current
Error Amplifier Transconductance
Output Voltage Line Regulation
Output Voltage Load Regulation
Oscillator Frequency
f
OSC
= 200kHz
f
OSC
= 200kHz
70kHz < f
OSC
< 700kHz,
70kHz < f
SYNC
< 700kHz
70
67
9
95
133
2.9
%
%
%
V
µA
µA
ms
ms
ns
ns
80
–6
2
1.8
4.5
30
30
85
100
10
85
100
10
115
115
mV
µA
mV
µA
3805fg
3
LTC3805
electrical characteristics
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 LTC3805 is tested under pulsed conditions such that T
J
≈ T
A
.
The LTC3805E is guaranteed to meet specifications from 0°C to 85°C.
Specifications over the –40°C to 85°C operating junction temperature
range are assured by design, characterization and correlation with
statistical process controls. The LTC3805I is guaranteed over the –40°C to
125°C operating junction temperature range, the LTC3805H is guaranteed
over the full –40°C to 150°C operating junction temperature range, and
the LTC3805MP is tested and guaranteed over the full –55°C to 150°C
operating temperature range. High junction temperatures degrade
operating lifetimes. Operating lifetime is derated at junction temperatures
greater than 125°C. Note that the maximum ambient temperature
consistant with these specifications is determined by specific operating
conditions in conjunction with board layout, the rated package thermal
resistance and other environmental factors.
Note 3:
T
J
is calculated from the ambient temperature T
A
and power
dissipation P
D
according to the following formula:
T
J
= T
A
+ (P
D
• 45°C/W)
Note 4:
Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency.
Note 5:
The LTC3805 is tested in a feedback loop that servos V
FB
to the
output of the error amplifier while maintaining I
TH
at the midpoint of the
current limit range.
Note 6:
Peak current sense voltage is reduced dependent on duty cycle
and an optional external resistor in series with the SENSE pin. For
details, refer to Programmable Slope Compensation in the Applications
Information section.
Note 7:
Guaranteed by design.
Note 8:
Overcurrent threshold voltage is reduced dependent on an
optional external resistor in series with the OC pin. For details, refer to
Programmable Overcurrent in the Applications Information section.
