LINER LTC1706EMS-85

LTC1706-85
VID Voltage Programmer
for Intel VRM 8.5
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FEATURES
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■
■
■
■
■
DESCRIPTIO
Fully Compliant with the Intel VRM 8.5 VID
Specification
Programs Regulator Output Voltage from 1.05V to
1.825V in 25mV Steps
Programs an Entire Family of Linear Technology
DC/DC Converters with 0.8V References
±0.25% Voltage Programming Accuracy
Built-In 40k Pull-Up Resistors on Program Inputs
Available in MSOP-10 Packaging
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APPLICATIO S
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The LTC®1706-85 is a precision, digitally programmed
resistive ladder which adjusts the output of any 0.8Vreferenced regulator. Depending on the state of the five
VID inputs, an output voltage between 1.05V and 1.825V
is programmed in 25mV increments.
The LTC1706-85 is designed specifically to program an
entire family of Linear Technology DC/DC converters in full
compliance with the Intel Voltage Regulator Module (VRM)
8.5 specification.
The LTC1706-85 programs the following Linear Technology DC/DC converter products: LTC1622, LTC1628,
LTC1629, LTC1702, LTC1735, LTC1735-1, LTC1772,
LTC1773, LTC1778, LTC1929, LTC3728 and LTC3729.
Server/Desktop Computers
Multiprocessor Workstations and Servers
Multiphase Processor Power Supply
Consult factory for additional DC/DC converter products
compatible with the LTC1706-85.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Pentium is a registered trademark of Intel Corporation.
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TYPICAL APPLICATIO
VID Controlled High Current 4-Phase DC/DC Converter (Simplified Block Diagram)
VIN
4.5V TO 22V
VOS+
VOS–
INTVCC
VID25
FROM
µP
LTC1629
SENSE
VID1 LTC1706-85
VID2
RSENSE1
SW1
VCC
VID0
VIN
TG1
VDIFFOUT
+
BG1
VOUT
1.05V TO 1.825V
UP TO 80A
COUT
VIN
PGND
SGND
FB
VID3
GND
TG2
EAIN
RSENSE2
SW2
ITH
CLKOUT
BG2
VIN
4.5V TO 22V
PLLIN
VIN
LTC1929
TG1
RSENSE3
SW1
BG1
PGND
VIN
SGND
EAIN
ITH
NOTE: UP TO SIX LTC1629s/LTC1929s CAN BE PARALLELED
TO DELIVER AS MUCH AS 200A
TG2
RSENSE4
SW2
BG2
1706-85 TA01
170685f
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LTC1706-85
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ABSOLUTE
AXI U RATI GS
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PACKAGE/ORDER I FOR ATIO
(Notes 1, 2)
Input Supply Voltage (VCC) ..........................– 0.3V to 7V
VID Input Pins .............................................– 0.3V to 7V
SENSE Pin ...................................................– 0.3V to 7V
FB Pin ..........................................................– 0.3V to 7V
Operating Temperature Range (Note 3) .. – 40°C to 85°C
Junction Temperature ........................................... 110°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART
NUMBER
TOP VIEW
VID25
VID0
VID1
VID2
VCC
1
2
3
4
5
10
9
8
7
6
FB
GND
NC
VID3
SENSE
LTC1706EMS-85
MS
PART MARKING
MS PACKAGE
10-LEAD PLASTIC MSOP
TJMAX = 110°C, θJA = 200°C/W
LTYQ
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C.
2.7V ≤ VCC ≤ 5.5V, VID25 = VID0 = VID1 = VID2 = VID3 = NC unless otherwise noted. (Note 3)
SYMBOL
PARAMETER
CONDITIONS
MIN
VCC
Operating Supply Voltage Range
IVCC
Supply Current
RFB1
Resistance Between SENSE and FB
VOUT(ERROR)
Output Voltage Accuracy
1.050 ≤ VSENSE ≤ 1.825V
RPULLUP
Pull-Up Resistance on VID
VDIODE = 0.6V (Note 5)
28
VIH
Minimum High Level Input Voltage (VID Inputs)
VCC = 3.3V
2
VIL
Maximum Low Level Input Voltage (VID Inputs)
VCC = 3.3V
IIN
Input Leakage Current (VID Inputs)
VCC < VID < 7V (Note 5)
TYP
2.7
(Note 4)
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: All voltages are with respect to GND pin.
Note 3: The LTC1706-85 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 4: Supply current is specified with all VID inputs floating. Due to the
internal pull-ups on the VID pins, the supply current will increase
●
6
●
– 0.25
MAX
UNITS
5.5
V
1
10
µA
10
14
kΩ
0.25
%
56
kΩ
40
V
0.01
0.8
V
±1
µA
depending on the number of grounded VID lines. Each grounded VID line
will draw approximately [(VCC – 0.6)/40]mA. If the VID inputs are left
unconnected, they will float to VCC at a rate controlled by parasitic
capacitance. Until the VID inputs reach their final states, slightly higher
IVCC current may be observed. (See the Operation section for more detail.)
Note 5: Each built-in pull-up resistor attached to the VID inputs also has a
series diode connected to VCC to allow input voltages higher than the VCC
supply without damage or clamping. (See Operation section for further
details.)
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LTC1706-85
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TYPICAL PERFOR A CE CHARACTERISTICS
Typical Error % vs Temperature
Typical Error % vs Output Voltage
0.25
0.25
TA = 25°C
ERROR (%)
ERROR (%)
VOUT = 1.05V
0
–0.25
1.0
1.2
1.6
1.4
OUTPUT VOLTAGE (V)
0
–0.25
–50
1.8
VOUT = 1.325V
VOUT = 1.825V
0
50
TEMPERATURE (°C)
1706-85 G01
100
1706-85 G02
VID Pullup Current vs Temperature
RFB1 vs Temperature
10.10
70
VID PULL-UP CURRENT (µA)
VCC = 3.3V
VID PIN UNDER TEST = 0V
RFB1 (kΩ)
10.05
10.00
9.95
9.90
–50
0
50
TEMPERATURE (°C)
65
60
55
–50
100
0
50
TEMPERATURE (°C)
1706-85 G03
1706-85 G04
Supply Current vs Temperature
Supply Current vs Supply Voltage
1.0
1.0
ALL VID INPUTS OPEN
TA = 25°C
VCC = 5V
0.5
VCC = 3.3V
SUPPLY CURRENT (µA)
ALL VID INPUTS OPEN
SUPPLY CURRENT (µA)
100
0.5
VCC = 2.7V
0
–50
0
50
TEMPERATURE (°C)
100
1706-85 G05
0
2.5
3.0
3.5 4.0
4.5 5.0
SUPPLY VOLTAGE (V)
5.5
6.0
1706-85 G06
170685f
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LTC1706-85
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PI FU CTIO S
VID25 (Pin 1): Programming Input. GND = LOW,
VCC or Float = HIGH. Refer to Table 1 for programming
information. Connect to associated VID pin of µP.
SENSE (Pin 6): Regulator Output Voltage. Connect directly to regulator output sense node or VDIFFOUT when
used with the LTC1929 or LTC1629.
VID0 (Pin 2): Programming Input. GND = LOW,
VCC or Float = HIGH. Refer to Table 1 for programming
information. Connect to associated VID pin of µP.
VID3 (Pin 7): Programming Input. GND = LOW,
VCC or Float = HIGH. Refer to Table 1 for programming
information. Connect to associated VID pin of µP.
VID1 (Pin 3): Programming Input. GND = LOW,
VCC or Float = HIGH. Refer to Table 1 for programming
information. Connect to associated VID pin of µP.
NC (PIN 8): No Connect.
VID2 (Pin 4): Programming Input. GND = LOW,
VCC or Float = HIGH. Refer to Table 1 for programming
information. Connect to associated VID pin of µP.
GND (Pin 9): Ground. Connect to regulator signal ground.
FB (Pin 10): Feedback Input. Connect to the 0.8V feedback
pin of a compatible regulator or the EAIN pin of the
LTC1929 or LTC1629.
VCC (Pin 5): Power Supply Voltage. May range from 2.7V
to 5.5V.
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BLOCK DIAGRA
VCC
40k
VID25 1
VCC
VCC
5
6
40k
SENSE
RFB1
10k
VID0 2
VCC
10 FB
SWITCH
CONTROL
LOGIC
RFB2
9
40k
GND
VID1 3
1706-85 BD
VCC
VCC
40k
VID2 4
40k
VID3 7
170685f
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LTC1706-85
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OPERATIO
The LTC1706-85 is a precision programmable resistive
divider designed specifically for use with an entire family
of Linear Technology Corporation DC/DC switching regulators with 0.8V internal reference and feedback voltages.
The LTC1706-85 programs an output voltage ranging
from 1.050V to 1.825V in 25mV steps, depending on the
state of the VID input pins. The LTC1706-85 in conjunction with a Linear Technology DC/DC switching regulator
can be used to create a high performance voltage regulator meeting all the requirements of the Intel VRM 8.5
specification.
input should be grounded or driven to a low state. The
VID inputs must be driven with a maximum VIL of 0.8V
(VCC = 3.3V).
When a VID input is grounded or pulled low with a logic
gate, the power supply current will increase because of
the resistor from VCC through the series diode to the
input. This increase in current is calculated from:
IQ = N • (VCC – VDIODE)/RPULLUP
Voltage Sensing and Feedback Pins
where N is the number of grounded VID inputs. With
typical values of VCC = 3.3V, VDIODE = 0.6V and RPULLUP
= 40k, each grounded VIN input will sink approximately
68µA.
The LTC1706-85 operates by closing the loop between
the output node and the feedback node of the regulator
with an appropriate resistive divider network. The “top”
feedback resistor, RFB1, connected between SENSE and
FB, is a fixed value of typically 10k. The “bottom” feedback
resistor, RFB2, is set by the five VID inputs to generate the
desired regulator output voltage. Feedback resistors R FB1
and RFB2 are matched and temperature stable in order to
provide a highly accurate output voltage.
To apply a digital high state the input can be either floated,
connected to VCC or driven by a logic gate. The VID inputs
should be driven with a minimum VIH of 2V (VCC = 3.3V).
Because of the diode between VCC and the pull-up resistor, the maximum VIH is not limited to VCC. The VID inputs
can be driven higher than VCC without being clamped or
damaged. This allows the LTC1706-85 to be fully logic
compatible and operational over a wide input voltage
range, up to the 7V absolute maximum rating.
The FB pin is a sensitive node in the circuit. Care should
be taken to minimize the layout distance between the
LTC1706-85 FB node and the regulator feedback node. In
addition, it is important to keep tight ground connections
between the two chips.
When used with the LTC1629 and LTC1929, the
LTC1706-85’s FB, SENSE, VCC and GND pins should be
connected respectively to the EAIN, VDIFFOUT, INTVCC and
SGND pins of the LTC1629 and LTC1929. The result of this
application is a precisely controlled, multiphase, variable
output voltage supply applicable to any low output voltage
system such as a personal computer, workstation or
network server.
VID Inputs
The desired output voltage is obtained by applying the
proper voltage or float condition to the five digital VID
inputs. Table␣ 1 shows the translation table with each input state and the corresponding regulator output voltage.
This translation is derived from and adheres to the Intel
VRM 8.5 specification.
Each VID input is pulled up by a 40k resistor in series with
a diode connected to VCC. To produce a digital low a VID
In addition to the LTC1629 and LTC1929, the LTC1706-85
also programs a whole family of LTC DC/DC converters
that have an onboard 0.8V reference. The LTC1628,
LTC1735 and LTC1622 are just a few of the high efficiency
step-down switching regulators that will work equally well
with the LTC1706-85. Contact LTC Marketing for a more
complete listing of compatible DC/DC regulators.
170685f
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LTC1706-85
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OPERATIO
Table 1. VID Inputs and Corresponding Output Voltage
CODE
VID3
VID2
VID1
VID0
VID25
VOLTAGE
CODE
VID3
VID2
VID1
VID0
VID25
VOLTAGE
00000
GND
GND
GND
GND
GND
1.250
10000
Float
GND
GND
GND
GND
1.650
00001
GND
GND
GND
GND
Float
1.275
10001
Float
GND
GND
GND
Float
1.675
00010
GND
GND
GND
Float
GND
1.200
10010
Float
GND
GND
Float
GND
1.600
00011
GND
GND
GND
Float
Float
1.225
10011
Float
GND
GND
Float
Float
1.625
00100
GND
GND
Float
GND
GND
1.150
10100
Float
GND
Float
GND
GND
1.550
00101
GND
GND
Float
GND
Float
1.175
10101
Float
GND
Float
GND
Float
1.575
00110
GND
GND
Float
Float
GND
1.100
10110
Float
GND
Float
Float
GND
1.500
00111
GND
GND
Float
Float
Float
1.125
10111
Float
GND
Float
Float
Float
1.525
01000
GND
Float
GND
GND
GND
1.050
11000
Float
Float
GND
GND
GND
1.450
01001
GND
Float
GND
GND
Float
1.075
11001
Float
Float
GND
GND
Float
1.475
01010
GND
Float
GND
Float
GND
1.800
11010
Float
Float
GND
Float
GND
1.400
01011
GND
Float
GND
Float
Float
1.825
11011
Float
Float
GND
Float
Float
1.425
01100
GND
Float
Float
GND
GND
1.750
11100
Float
Float
Float
GND
GND
1.350
01101
GND
Float
Float
GND
Float
1.775
11101
Float
Float
Float
GND
Float
1.375
01110
GND
Float
Float
Float
GND
1.700
11110
Float
Float
Float
Float
GND
1.300
01111
GND
Float
Float
Float
Float
1.725
11111
Float
Float
Float
Float
Float
1.325
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TYPICAL APPLICATIO S
30A, 2-Phase VID Controlled Power Supply
VIN
12V
OPTIONAL SYNC
CLOCK IN
10Ω 10Ω
0.33µF
1
TG1
3
SENSE1–
SW1
2
FROM
µP
3
4
7
5
VCC
SENSE
VID0
VID1
6
0.33µF
VID25
7
6
3300pF
100pF
100pF
10k
LTC1706-85
8
9
10
VID2
FB
10
VID3
GND
BOOST1
PLLFLTR
PLLIN
NC
ITH
VIN
BG1
EXTVCC
LTC1929
SGND
INTVCC
PGND
VDIFFOUT
BG2
VOS–
BOOST2
12
VOS+
SW2
14
VIN: 12V
VOUT: 1.05V TO 1.825, 30A
M1 TO M6: FDS7760A
L1 TO L2: 1µH SUMIDA CEP125-IROMC-H
D7 TO D10: CENTRAL CMDSH-3TR
COUT: PANASONIC EEFUEOG181R
EAIN
11
1000pF 13
9
NC
SENSE1+
1000pF 4
5
RUN/SS
2
SENSE2–
SENSE2
+
TG2
AMPMD
L1
28
27
75k
4
1 0.003Ω 2
26
25
0.47µF
D1
MBRS
340T3
M1
10Ω
24
M2
M3
23
22µF
6.3V
22
21 D7
20 D8
19
1µF
6.3V
18
17
16
1µF 150µF, 16V
16V
×2
+
+
×5
180µF
4V
GND
M5
M6
15
VOUT
1.05V TO
1.825V
30A
D2
MBRS
340T3
M4
0.47µF
1
3
L2
24k
3
5V
+
1
0.003Ω
2
4
10Ω 10Ω
170685f
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LTC1706-85
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TYPICAL APPLICATIO S
VID Controlled High Current 70A 4-Phase Power Supply
OPTIONAL SYNC
CLOCK IN
10Ω 10Ω
2
0.33µF
3
1000pF 4
5
2
FROM
µP
3
4
7
VCC
SENSE
VID0
VID1
6
0.33µF
VID25
7
6
3300pF
100pF
10k
LTC1706-85
8
100pF
9
10
VID2
FB
10
VID3
GND
+
SENSE1–
EAIN
BOOST1
PLLFLTR
PLLIN
TG1
SW1
VIN
LTC1629
BG1
NC
EXTVCC
ITH
INTVCC
SGND
PGND
VDIFFOUT
BG2
VOS–
11
VOS+
VOS–
12
VOS+
SW2
SENSE2–
TG2
SENSE2+
AMPMD
1000pF 13
9
SENSE1
CLKOUT
14
BOOST2
L1
28
3 0.002Ω 4
1
2
5V
27
26
0.47µF
25
M1
10Ω
24
M2
M3
22
1µF
16V
22µF
6.3V
21 D7
20 D8
1µF
6.3V
19
150µF, 16V
×2
+
18
+
×3
470µF, 6.3V
KEMET CAP
GND
M4
0.47µF
17
M5
16
M6
15
VOUT
1.05V TO
1.825V
70A
D2
MBRS
340T3
1
2
3 0.002Ω 4
L2
24k
D1
MBRS
340T3
23
10Ω 10Ω
75k
10Ω 10Ω
1
2
3
47pF
1000pF 4
10k
5
0.01µF
6
1nF
7
8
100pF
9
VIN: 12V
VOUT: 1.05V TO 1.825, 70A
M1 TO M12: Si7440DP
L1 TO L4: 1µH SUMIDA CEP125-IROMC-H
D7 TO D10: CENTRAL CMDSH-3TR
COUT: KEMET T510X477M006AS
VDIFFOUT
10
VOS–
11
VOS+
12
13
1000pF
14
NC
RUN/SS
SENSE1+
TG1
SENSE1–
SW1
BOOST1
EAIN
VIN
PLLFLTR
BG1
PLLIN
EXTVCC
PHASMD
ITH
SGND
VDIFFOUT
LTC1629
INTVCC
PGND
BG2
VOS–
BOOST2
VOS+
SW2
SENSE2–
TG2
SENSE2+
AMPMD
L3
28
26
0.47µF
25
10Ω
24
22
20
1µF
6.3V
D9
D10
M9
M8
1µF
23
21
M7
22µF
6.3V
+
D3
MBRS
340T3
×3
470µF, 6.3V
KEMET CAP
150µF, 16V
×2
+
GND
VIN
12V
19
18
17
0.47µF
M10
M12
M11
16
15
L4
10Ω
3 0.002Ω 4
1
2
5V
27
+
1
5
RUN/SS
+
1
10Ω
D4
MBRS
340T3
1
2
3 0.002Ω 4
1706-85 TA03
170685f
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
7
LTC1706-85
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PACKAGE DESCRIPTIO
MS Package
10-Lead Plastic MSOP
(Reference LTC DWG # 05-08-1661)
3.00 ± 0.102
(.118 ± .004)
(NOTE 3)
0.889 ± 0.127
(.035 ± .005)
5.23
(.206)
MIN
10 9 8 7 6
3.2 – 3.45
(.126 – .136)
0.254
(.010)
3.00 ± 0.102
(.118 ± .004)
NOTE 4
4.88 ± 0.10
(.192 ± .004)
DETAIL “A”
0.497 ± 0.076
(.0196 ± .003)
REF
0° – 6° TYP
GAUGE PLANE
0.50
3.05 ± 0.38
(.0197)
(.0120 ± .0015)
BSC
TYP
RECOMMENDED SOLDER PAD LAYOUT
1 2 3 4 5
0.53 ± 0.01
(.021 ± .006)
DETAIL “A”
0.86
(.034)
REF
1.10
(.043)
MAX
0.18
(.007)
NOTE:
1. DIMENSIONS IN MILLIMETER/(INCH)
2. DRAWING NOT TO SCALE
3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS.
MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006") PER SIDE
4. DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS.
INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.152mm (.006") PER SIDE
5. LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX
SEATING
PLANE
0.17 – 0.27
(.007 – .011)
0.50
(.0197)
TYP
0.13 ± 0.05
(.005 ± .002)
MSOP (MS) 1001
RELATED PARTS
PART NUMBER
LTC1622
LTC1628/LTC1628-PG
LTC1629/LTC1629-PG
LTC1702/LTC1703
LTC1706-81/LTC1706-82
LTC1709/LTC1709-8
LT1709-85
LTC1735
DESCRIPTION
Sychnronizable Low Voltage Step-Down Controller
Dual High Efficiency, 2-Phase Sync Step-Down Controller
PolyPhase® High Efficiency Step-Down DC/DC Controller
Dual High Efficiency, 2-Phase Sync Step-Down Controller
VID Voltage Programmer with Desktop Code
2-Phase Sync Step-Down Controller with 5-Bit Desktop VID
2-Phase, 5-Bit VID, Current Mode High Efficiency
Synchronous Step-Down Switching Regulator
High Efficiency Sync Step-Down Controller
COMMENTS
8-Pin MSOP, 2V ≤ VIN ≤ 10V, 550kHz, Burst Mode® Operation
Constant Freq, Standby, 5V and 3.3V LDOs, 3.5V ≤ VIN ≤ 36V
Expandable Up to 12 Phases, Up to 200A, Remote Sense Diff Amp
550kHz, 25MHz GBW, No RSENSETM, 2.7V ≤ VIN ≤ 7V
VRM 8.2-VRM 8.4, VOUT Range: 1.3V to 3.5V
4V ≤ VIN ≤ 36V, PLL, 36-Pin SSOP, Current Mode Operation
4V ≤ VIN ≤ 36V, 36-Pin SSOP VRM 8.5 Compatiable
Burst Mode Operation, 16-Pin Narrow SSOP, Fault Protection,
3.5V ≤ VIN ≤ 36V
LTC1736
High Efficiency Sync Buck Controller with 5-Bit Mobile VID GN-24, Power Good, Output Fault Protection, 3.5V ≤ VIN ≤ 36V
LTC1772
SOT-23 Low Voltage Step-Down Controller
6-Pin SOT-23, 2.5V ≤ VIN ≤ 10V, 550kHz, Burst Mode Operation
LTC1773
Synchronous Step-Down DC/DC Controller
Up to 95% Efficiency, 550kHz Operation, 2.65V ≤ VIN ≤ 8.5V,
0.8 ≤ VOUT ≤ VIN
LTC1778
Wide Operating Range Step-Down Controller
No RSENSE, VIN up to 36V, Current Mode Power Good
LTC1929/LTC1929-PG
2-Phase Sync Step-Down Controller
Current Mode Operation, IOUT Up to 40A, 3.5V ≤ VIN ≤ 36V
LTC3728
550kHz, 2-Phase Dual Output Synchronous
Synchronizable, Current Mode, 3.5V ≤ VIN ≤ 36V,
Step-Down Controller
IOUT up to 25A
LTC3729
550kHz, PolyPhase, High Efficiency Synchronous
Current Mode, 4V ≤ VIN ≤ 36V, 28-Lead SSOP package
Step-Down Switching Regulator
Burst Mode and PolyPhase are registered trademarks of Linear Technology Corporation.
No RSENSE is a trademark of Linear Technology Corporation.
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Linear Technology Corporation
LT/TP 1202 2K • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2001