DC1717A - Demo Manual

DEMO MANUAL DC1717A
LTC4417
Prioritized PowerPath™ Controller
Description
Demonstration circuit DC1717A uses the LTC®4417 to
arbitrate between three input supply rails, selecting the
highest priority, valid supply to power the load. The rail’s
priority is defined by the input connection (V1-V3). Each
rail has overvoltage and undervoltage thresholds set by
external resistors. If the highest priority rail voltage falls
out of the defined window (overvoltage or undervoltage),
the rail with the next highest priority, which is valid, is
Performance Summary
enabled and powers the load. Two or more LTC4417s
can be cascaded to provide switchover between more
than three rails.
Design files for this circuit board are available at
http://www.linear.com/demo/DC1717A
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
PowerPath is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
Specifications are at TA = 25°C
SYMBOL
PARAMETER
V1-V3, VOUT
V1 to V3, VOUT Operating Supply Range
CONDITIONS
MIN
ΔVG
Open (VS-VG) Clamp Voltage
VOUT = 11V, G1 to G3 = Open
5.4
TYP
2.5
MAX
UNITS
36
V
6.2
6.7
V
ΔVG(SOURCE)
Sourcing (VS-VG) Clamp Voltage
VOUT = 11V, I = –10µA
5.8
6.6
7
V
ΔVG(SINK)
Sinking (VS-VG) Clamp Voltage
VOUT = 11V, I = 10µA
4.5
5.2
6
V
ΔVG(OFF)
G1 to G3 Off (VS-VG) Threshold
V1 = V2 = V3 = 2.8V, VOUT = 2.6V, G1 to G3 Rising Edge
0.12
0.35
0.6
V
ΔVG(SLEW,ON)
G1 to G3 Pull-Down Slew Rate
VOUT = 11V, CGATE = 10nF
4
9
20
V/µs
ΔVG(SLEW,OFF)
G1 to G3 Pull-Up Slew Rate
VOUT = 11V, CGATE = 10nF
7.5
13
22
V/µs
IGATE(LOW)
G1 to G3 Low Pull-Down Current
VOUT = 2.6V, V1 to V3 = 2.8V, (G1 to G3) = ΔVG + 300mV
0.8
2
7
µA
VREV
Reverse Voltage Threshold
Measure (V1 to V3) – VOUT, VOUT Falling
30
120
200
mV
VOUT = 11V, CGATE = 10nF
0.7
tG(SWITCHOVER) Break-Before-Make Time
2
3
µs
0.2
0.55
V
5
8
13
µs
SHDN Rising
0.4
0.8
1.2
V
SHDN, EN Pull-Up Current
SHDN = EN = 0V
–0.5
–2
–5
µA
VOV_UV(THR)
OV1 to O3, UV1 to UV3 Comparator
Threshold
VOUT = 11V, OV1 to OV3 Rising, UV1 to UV3 Falling
0.985
1
1.015
V
VOV_UV(HYS)
OV1 to O3, UV1 to UV3 Comparator
Hysteresis
VOUT = 11V
15
30
45
mV
tVALID
V1 to V3 Validation Time
100
256
412
ms
V1
Operating Voltage of Channel V1
9.6
12
14.4
V
VVALID(OL)
VALID1 to VALID3 Output Low Voltage
tPVALID(OFF)
VALID1 to VALID3 Delay OFF from
OV/UV Fault
VSHDN(THR)
SHDN Threshold Voltage
VSHDN_EN(HYS)
SHDN, EN Threshold Hysteresis
ISHDN_EN
I = 1mA, (V1 to V3) = 2.5V, VOUT = 0V
100
mV
V2
Operating Voltage of Channel V2
4
5
6
V
V3
Operating voltage of Channel V3
6.4
8
9.6
V
ILOAD
Load Current
AVI
Auxiliary Voltage Input
24
V
2
6
A
dc1717afa
1
DEMO MANUAL DC1717A
Overview
The LTC4417 controls three sets of external back-to-back
P-channel MOSFETs to connect the proper rail to the
load. Precision comparators are used to monitor each of
the three input rails for both UV and OV conditions. The
highest priority input supply whose voltage is within its
respective OV/UV window for at least 256ms is considered valid and connected to the load. Low signals on the
VALID1, VALID2, and VALID3 pins indicate validation of
the V1, V2, and V3 voltages.
DC1717A is designed to operate from inputs of 12V,
5V, and 8V, applied to V1, V2 and V3 respectively. The
valid range of each supply is ±20%, as set by OV and UV
comparators and their associated resistive dividers. V1
has the highest priority, V3 has the lowest. The highest
priority input that is also within its valid range is selected
to power the output. V1, V2 and V3 inputs are protected
against input glitches of up to ±42V. Maximum load current is 2A, limited by MOSFET capability.
Logic and LEDs are included to provide visual information
about the operating status. These circuits are powered
from a 6V to 24V auxiliary voltage input (AVI) which is
regulated by an LT3060 (U4) to 5V. This auxiliary 5V rail
also powers 100kΩ pull-ups for VALID pins. AVI must be
present in order for the board to operate. See the Modification section for a means of eliminating AVI.
Operating Principles
To eliminate back-and-forth switching during rail switchover, the LTC4417 provides a 30mV hysteresis in the OV and
UV comparators, and an externally adjustable current mode
hysteresis using the OV/UV resistive dividers. DC1717A’s
input reference hysteresis is 6%, and can be changed to
3% by moving the JP1 jumper to the 30mV position.
The controller’s “break-before-make” switching method
prevents cross conduction between input channels and
reverse current from the output capacitor into the selected
input supply.
Each channel’s control circuit of the LTC4417 has a REV
comparator, which monitors the connecting input supply
and output load voltage. The REV comparator delays the
connection until the output voltage droops 120mV below
the input voltage. This prevents reverse current.
The LTC4417 has two common control pins: EN and SHDN.
Pulling the EN pin below 1V turns off all external back-toback P-channel MOSFETs. When this pin is driven above
1V, the highest priority valid channel is connected to the
load. All these actions are provided without resetting the
256ms OV/UV timers.
Pulling the SHDN pin below 0.8V turns off all external
back-to-back P-channel MOSFETs, placing the controller
2
in a low current state and resetting the 256ms timers
used to validate input rail voltages. It requires at least
256ms to validate each rail voltage after the SHDN pin
signal goes high.
The LTC4417 features two different driving modes for the
P-channel MOSFET gates.
One mode is provided by the internal soft-start circuitry,
which limits output voltage slew rate to no more than
5V/ms. As the highest output voltage slew rate, usually, can
impose the highest requirements for circuit components,
5V/ms should be taken into account as a worst case for
component selection.
The soft-start circuitry is enabled each time under the
following conditions:
• If the LTC4417 is first powered on, or
• If SHDN is forced low, or
• If VOUT falls below ~0.7V
Soft-start is disabled when:
• any channel turns off, including the channel that is soft
starting.
• 32ms validation delay time has elapsed during the softstart interval.
dc1717afa
DEMO MANUAL DC1717A
Operating Principles
The other driving mode of the P-channel MOSFETs is used
in the voltage switching operation, when the higher priority
rail replaces the rail losing validity. The gate driver operates with a fixed current, which is defined by the external
component parameters RS and CS shown in Figure 1.
12V WALL
ADAPTER
V1
+
M1
IRF7324
M2
CIN1
68µF
CS
DS
BAT54
CVS1
The LTC4417 circuit designer should select the value of
RS and CS based on the MOSFET parameters, power rail
source characteristics, acceptable output voltage droop
during transient, and the value of load capacitance.
VS1
G1
VOUT
LTC4417
RS
+
VOUT
CL
47µF
Figure 1
Design Procedure for Modification of DC1717A
The valid input range for any supply is controlled by the
OV and UV comparators with resistive dividers (R4-R13).
See the LTC4417 data sheet for design equations to select
resistors to match a particular requirement.
Dual MOSFETs, Q1-Q3, may be replaced with single devices
Q4-Q9 by simply removing Q1-Q3. Pads for Q4-Q9 are
located on the bottom side of the board.
The requirement for AVI may be eliminated by removing
jumpers JP2 and JP3, and removing resistor R19. This
modification leaves the LEDs unpowered and the inputs
of U2 and U3 clamp the VALID pins at 0.7V, but otherwise
leaves the LTC4417 operating autonomously.
The following design considerations and equations demonstrate the interrelation of the main component values
and transient parameters in the rail transitions, when the
output voltage exceeds 0.7V. The variables CS and RS
used in the design equations correspond to the following
board components:
The slew rate of the output voltage can be expressed as
a function of CS:
dVOUT dVCS VSINK – | VTHRES |
=
=
dt
dt
RS • CS
(1)
where:
• VSINK is the LTC4417 parameter rated in the data sheet
as ∆VG(SINK) = 4.5V-6V.
• VTHRES is the P-channel gate threshold voltage, which
is between –1.5V and –3.5V for the Si7905DN installed
on the board.
• RS = 249Ω and CS = 47nF.
Given that dVOUT/dt is based on the transient time requirement, it is possible to define RS from equation 1.
The output voltage slew rate, dVOUT/dt, range for the circuit
with the listed parameters is between 85V/ms and 385V/ms.
• C20, R23 for V1 (+12V channel)
During the transition of rails, the load can be disconnected
from any rail for a time:
• C21, R26 for V2 (+5.0V channel)
TDISCON = tG(SWITCHOVER) + tpVALID(OFF) + tGATE_THRES
• C22, R28 for V3 (+8.0V channel)
To have dominant influence on the transient time CS should
be at least ten times larger than the P-channel MOSFET’s
reverse transfer capacitance (Miller). In this design, for
all rails, CS (C20, C21,and C22) equals 47nF.
Two first summands of the TDISCON are rated in the LTC4417
data sheet as:
tG(SWITCHOVER) = (0.3 to 3)µs
tpVALID(OFF) = (5 to 13)µs
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3
DEMO MANUAL DC1717A
Design Procedure for Modification of DC1717A
The second summand, tpVALID(OFF), should be taken into
account if the associated LTC4417 input does not have
any bypass capacitor and the rail can be disconnected
from the input instantly.
The third one must be calculated as:
⎡ ⎛ V
⎞⎤
tGATE _ THRES = RS • CS ⎢–In ⎜1– THRES ⎟⎥
VSINK ⎠⎦
⎣ ⎝
(2)
It is possible to determine the minimum capacitive load
required to hold the output up during switchover as a:
CLOAD(MIN) ≥
ILOAD(MAX) • TDISCON
VOUT(DROOPMAX)
(3)
where:
As shown in the equation (3), the use of external slew rate
control will add additional delay to the total switchover
time. Unfortunately, the actual components cannot be
chosen until the load capacitance is known. This circular
issue can only be resolved through an iterative process.
The process starts by calculating the CLOAD(MIN), assuming
that tGATE_THRES =10μs. For clarity this value will be labeled
CLOAD(INIT). Using the calculated CLOAD(INIT), calculate RS
from the expression of the TDISCON. To ensure the newly
calculated RS based on CLOAD(INIT) is sufficient, calculate
CLOAD with the calculated RS.
If CLOAD(INIT) (the initial calculated CLOAD) is higher than
the newly calculated CLOAD then the process is completed.
If the CLOAD(INIT) is lower than the newly calculated CLOAD,
calculate RS using the higher value and repeat this process.
• ILOAD(MAX) is the maximum load current, A
• VOUT(DROOPMAX) is the maximum acceptable voltage
droop, V
⎡ ⎛ V
⎞⎤
RS • CS ⎢–In ⎜1– THRES ⎟⎥ = 10µs
V
⎣ ⎝
SINK ⎠⎦
Calculate RS with CL(INIT)
Recalculate CL with RS
Is recalculated CL
lower than initial
CL(INIT)?
No
Done.
Use CL(INIT) and RS
Figure 2
4
dc1717afa
DEMO MANUAL DC1717A
Turrets
V1: 12V supply input; do not exceed ±42V.
V2: 5V supply input; do not exceed ±42V.
V3: 8V supply input; do not exceed ±42V.
GND: Adjacent ground connection for input supplies.
VOUT: Output for up to 2A load.
GND: Adjacent ground connection for load.
AVI: Auxiliary Voltage Input. 6V to 24V input regulated
by U4 to 5V for LEDs, logic and pull ups on various pins.
GND: Adjacent ground connection for auxiliary supply.
5V: 5V regulated output provided by U4, for powering
logic, LEDs and pull ups. Use this turret to verify that 5V
is present.
Each of the following turrets is a direct connection to the
like-name LTC4417 pin:
VALID1: pulled up with 100kOhm to auxiliary 5V supply.
VALID2: pulled up with 100kOhm to auxiliary 5V supply.
VALID3: pulled up with 100kOhm to auxiliary 5V supply.
EN: pulled up by 2μA internal to the LTC4417. Optional
R33 may be added as a pull-up to the auxiliary 5V power
supply.
SHDN: pulled up by 2μA internal to the LTC4417. Optional
R36 may be added as a pull-up to the auxiliary 5V power
supply.
CAS: used to cascade a second DC1717A. Connect the
CAS turret of the high priority DC1717A to the EN turret
of the lower priority DC1717A.
Grounds must be connected in common.
Jumpers
JP1, HYS: Add 30mV fixed hysteresis to the OV and UV
comparators, or 3% referred to actual supply input. In the
RHYS position input-referred hysteresis is set to 6.4%, as
controlled by R11. Default stuffing position is for 30mV.
JP2, EN: Directly controls EN pin. Default stuffing position
is ON, pulled up by internal 2μA current source.
LEDs
No more than one of D8, D9 and D10 will be illuminated
at any given moment:
D11, D16 and D17 indicate the presence of a valid input
on any of the three supplies:
D8: indicates power is being taken from V1.
D17: V1 is 12V±20%.
D9: indicates power is being taken from V2.
D11: V2 is 5V±20%.
D10: indicates power is being taken from V3.
D16: V3 is 8V±20%.
dc1717afa
5
DEMO MANUAL DC1717A
Quick Start Procedure
Refer to the Figure 3 for proper measurement equipment
setup and follow the procedure below:
Initially, the LTC4417 should be disabled by:
• placing the jumper JP2 (EN) header in the OFF position,
and
Connect 6Ω load resistor (30W) to the DC1717A output
turret or banana jack (VOUT). Do not use an electronic
load in constant current mode.
Turn on three power supplies. No additional LEDs should
light.
• placing the jumper JP3 (SHDN) header in the OFF
position
Change the jumper JP3 (SHDN) header position from
OFF to ON. Three LEDs (VALID1, VALID2, and VALID3)
validating the input rail voltages should light.
Connecting the auxiliary power source (6V to 24V) to
the DC1717A (AVI and GND turrets) lights the green LED
(LDO-D12) indicating the presence of auxiliary +5V supply
for powering logic.
Placing the jumper JP2 (EN) in the ON position turns on
the LTC4417 powering the load with 12V (2.0A). In an
initial power up the LTC4417 uses a fixed slew rate for the
output voltage, which should be not larger than 5V/ms.
With power off, connect three power supplies with output
voltages of 12V, 5V, and 8V to corresponding DC1717A
turrets or banana jacks V1(+12V), V2(+5V), V3(+8V),
and GND.
The prioritizing function is demonstrated by simply turning
off one or two of the V1, V2 and V3 supplies. The output
will be powered from the remaining supply of the highest priority. V1, V2 and V3 may be adjusted up and down
beyond ±20% to invalidate a given input.
12V
POWER
SUPPLY
5V
POWER
SUPPLY
6Ω
RESISTIVE
LOAD
8V
POWER
SUPPLY
Figure 3
6
dc1717afa
DEMO MANUAL DC1717A
Parts List
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
1
0
C1, C3, C5, C8
CAP., 1206
OPT
2
0
C2, C4, C6, C9
CAP., 2220
OPT
3
1
C7
CAP., ALUM., 47µF 50V 20% SMT
SUN ELECT., 50CE47BS
4
5
C10, C11, C12, C13, C15
CAP., X5R, 1µF 50V, 10%, 0603
MURATA, GRM188R61H105KAALD
5
1
C14
CAP., X5R 10µF 10V 20% 0805
TAIYO YUDEN LMK212ABJ106MG -T
6
1
C16
CAP., NPO 10nF 50V 5% 0805
NIC, NMC0805NPO103J50TRPF
7
3
C17, C18, C19
CAP., X5R 0.1µF 50V 10% 0805
TAIYO YUDEN UMK212BJ104KG-T
8
3
C20, C21, C22
CAP., X7R 0.047µF 50V, 10%, 0805
MURATA, GRM21BR71H473KA01L
9
3
D1, D2, D3
DIODE, TVS BI-DIRECTIONAL, 26V, 600W
DIODES/ZETEX SMBJ26CA-13-F
10
0
D7
ZENER DIODE, 5.1V SOD-123
OPT
11
8
D8-D12, D16, D17, D18
LED, GREEN, LED-ROHM-SML-01
ROHM, SML-012P8TT86
12
3
D13, D14, D15
DIODE, SCHOTTKY, SOD323
VISHAY SEMI., BAT42WS-E3-08
13
9
E1-E4, E6, E13-E16
TURRET, 0.094"
MILL-MAX 2501-2-00-80-00-00-07-0
14
6
E7, E8, E9, E10, E11, E12
TURRET, 0.063"
MILL-MAX 2308-2-00-80-00-00-07-0
15
3
JP1, JP2, JP3
HEADERS, SGL. ROW 3 PINS 2mm CTRS.
SAMTEC TMM-103-02-L-S
16
3
SHUNTS ON JP1-JP3 (1&2)
SHUNT, 2mm CTRS.
SAMTEC 2SN-BK-G
17
6
J1, J2, J3, J4, J5, J6
JACK, BANANA
KEYSTONE 575-4
18
3
Q1, Q2, Q3
DUAL P-CHAN., 40V POWERPAK1212-8-DUAL
VISHAY Si7905DN-T1-GE3
19
0
Q4, Q5, Q6, Q7, Q8, Q9
MOSFET P-CHAN., 40V, FDD4685, DPAK
OPT
20
1
Q10
XTOR N-CHAN., SOT23
DIODE INC., MMBTA42-7-F
21
1
Q11
XTOR N-CHAN., SOT23
DIODE INC., MMBT3904-7-F
22
1
R4
RES., CHIP 1.69M 0.125W 1% 0805
VISHAY, CRCW08051M69FKEA
23
3
R5, R8, R12
RES., CHIP 69.8k 0.125W 1% 0805
VISHAY, CRCW080569K8FKEA
24
3
R6, R9, R13
RES., CHIP 130k 0.125W 1% 0805
NIC, NRC10F1303TRF
25
1
R7
RES., CHIP 590k 0.125W 1% 0805
VISHAY, CRCW0805590KFKEA
26
1
R10
RES., CHIP 1.05M 0.125W 1% 0805
VISHAY, CRCW08051M05FKEA
27
1
R11
RES., CHIP 127k 0.1W 1% 0603
VISHAY, CRCW0603127KFKED
28
7
R14-R16, R20-R22, R29
RES., CHIP 1k 0.1W 5% 0603
VISHAY, CRCW06031K00JNEA
29
0
R17
RES., CHIP 845k 0.1W 1% 0603
OPT
30
0
R18
RES., CHIP 115k 0.06W 1% 0603
OPT
31
1
R19
RES., CHIP 30.9k 0.1W 1% 0603
VISHAY, CRCW060330K9FKEA
32
3
R23, R26, R28
RES., CHIP 249 0.1W 1% 0603
VISHAY, CRCW060249RFKEA
33
5
R30, R31, R32, R33, R36
RES., CHIP 100k 0.1W 5% 0603
NIC, NRC06J104TRF
34
1
R34
RES., CHIP 68k 0.25W 5% 1206
NIC, NRC12J683TRF
35
1
R35
RES., CHIP 240Ω 0.25W 1% 1206
VISHAY, CRCW1206240RFKEA
36
1
U1
I.C., POWERPATH CONTROLLER, QFN24UF-4×4
LINEAR TECH CORP. LTC4417CUF
37
3
U2,U3,U5
I.C., TRIPPLE 3-INPUT NOR GATE TSSOP14
NXP/PHILIPS SEMI. 74HC27PW
38
1
U4
I.C., LOW DROPOUT REG. TSOT23-8
LINEAR TECH CORP. LT3060ETS8-5
39
4
MH1-MH4
STANDOFF, NYLON, 0.50, 1/2"
KEYSTONE, 8833 (SNAP ON)
dc1717afa
7
A
B
C
D
GND
V3 (+8V)
V2 (+5V)
V1 (+12V)
E4
J6
E3
J5
E2
J2
E1
J1
V3
V2
V1
5
C17
0.1uF
50V
0805
C19
0.1uF
50V
0805
C18
0.1uF
50V
0805
OV1
R8
69.8K
0805
OV2
R12
69.8K
0805
OV3
R13
130K
0805
R10
1.05M
0805
UV3
R9
130K
0805
R7
590K
0805
UV2
V3
R5
69.8K
0805
R6
130K
0805
R4
1.69M
0805
V2
V1
C8
OPT
1206
C3
OPT
1206
C1
OPT
1206
UV1
D3
SMBJ26CA
D2
SMBJ26CA
D1
SMBJ26CA
C9
OPT
2220
C4
OPT
2220
C2
OPT
2220
OV3
UV3
V3
OV2
UV2
V2
OV1
UV1
V1
VS1 G1
18 17
C11
1uF
50V
VS2
14
VS3
GND
10
EP
25
U1
LTC4417
VS2 G2
16 15
C12
1uF
50V
VS3
G3
13
R26
249
VOUT
CAS
HYS
SHDN
EN
VALID3
VALID2
VALID1
4
2
2
1
2
1
3
1
11
24
23
22
9
8
7
R28
249
12
FG3
8 7
FG2
Q3
Si7905DN
Q2
Si7905DN
8 7
R23
249
8 7
FG1
Q1
Si7905DN
4
3
4
3
4
1. ALL RESISTORS ARE IN OHMS, 0603.
ALL CAPACITORS ARE IN MICROFARADS, 0603.
2. INSTALL SHUNTS ON JUMPERS AS SHOWN.
NOTES: UNLESS OTHERWISE SPECIFIED
6
5
19
4
3
20
2
1
21
C10
1uF
50V
VS1
4
1
2
1
2
1
G1
C21
0.047uF
50V
0805
5V
5V
JP1
HYS
30mV
RHYS
R32
100k
5V
CUSTOMER NOTICE
1
2
3
5V
FG3
VS3
FG2
VS2
FG1
VS1
R33
100k
R34
68k
1206
2
1
2
3
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
1
R35
240
1206
OFF
ON
5V
2
SCALE = NONE
VLAD O.
KIM T.
JP3
C5
OPT
1206
C6 +
OPT
2220
VOUT
1
E12
E11
E10
E9
E8
E7
J4
E6
E16
J3
DATE
GND
VOUT
2A MAX
07-23-15
CAS
SHDN
EN
VALID3
VALID2
VALID1
EN
/VALID3
/VALID2
/VALID1
VLAD O.
APPROVED
DATE:
N/A
SIZE
IC NO.
Thursday, July 23, 2015
1
SHEET
1
OF
2
3
REV.
PRIORITIZED POWERPATH CONTROLLER
LTC4417CUF
DEMO CIRCUIT 1717A
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900 www.linear.com
Fax: (408)434-0507
LTC Confidential-For Customer Use Only
C7
47uF
50V
SANYO
50CE47BS
PRODUCTION
DESCRIPTION
REVISION HISTORY
TECHNOLOGY
OFF
SHDN
ON
3
__
1
2
3
REV
ECO
TITLE: SCHEMATIC
R36
100k
VOUT
D18
GRN
Q10
MMBTA42
LED DRIVER
1
APPROVALS
JP2
EN
Q11
MMBT3904
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES.
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
APP ENG.
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
R11
127k
R30
100k
G3
R31
100k
C22
0.047uF
50V
0805
D15
BAT42WS-V
6 5
G2
D14
BAT42WS-V
6 5
3
C20
0.047uF
50V
0805
D13
BAT42WS-V
6 5
3
3
2
3
12
2
8
2
5
A
B
C
D
DEMO MANUAL DC1717A
Schematic Diagram
dc1717afa
A
B
C
R19
30.9K
GND
E15
5
C13
1uF
50V
1
5
7
9
10
11
3
4
5
1
2
13
7
9
10
11
3
4
5
SHDN
IN
U4
LT3060ETS8-5
D7
MMSZ5231BT1G
5.1V
OPT
AUXILIARY VOLTAGE INPUT
6V - 24V
E14
/VALID2
/VALID1
EN
/VALID3
1
1
2
13
VDD
GND
ADJ
OUT
7
6
VDD
U3
74HC27PW
GND
REF/BYP
2
U2
74HC27PW
14
8
6
12
14
8
6
12
R18
115k
OPT
R17
845k
OPT
5V
5V
4
4
C16
10nF
50V
0805
V3
GRN
D10
V2
GRN
D9
V1
GRN
C14
10uF
10V
0805
1
1
1
D8
C15
1uF
50V
2
2
2
LDO
D12
GRN
R29
1k
R16
1k
R15
1k
R14
1k
5V
VOUT POWER SOURCE
1
D
2
3 GND
4 GND
GND
8
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.
2
3
2
5V
2
SCALE = NONE
VLAD O.
KIM T.
APPROVALS
14
7
VDD
8
9
10
11
GND
6
12
Q8
FDD4685
Q6
FDD4685
Q4
FDD4685
3
4
5
1
2
13
U5
74HC27PW
V3
1
V2
1
V1
1
1
1
1
OPTIONAL CIRCUIT
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
CUSTOMER NOTICE
5V
/VALID3
/VALID2
/VALID1
FG3
VS3
FG2
VS2
FG1
VS1
3
2
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES.
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
APP ENG.
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
E13
3
3
2
Q9
FDD4685
VOUT
Q5
FDD4685
VOUT
Q7
FDD4685
VOUT
3
2
2
VALID3
GRN
D16
VALID2
GRN
D11
VALID1
GRN
D17
R21
1k
R20
1k
R22
1k
DATE:
N/A
IC NO.
Thursday, July 23, 2015
1
SHEET
2
OF
2
REV.
PRIORITIZED POWERPATH CONTROLLER
SIZE
3
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900 www.linear.com
Fax: (408)434-0507
LTC Confidential-For Customer Use Only
1
LTC4417CUF
DEMO CIRCUIT 1717A
TECHNOLOGY
2
2
2
TITLE: SCHEMATIC
1
1
1
VALID STATUS
3
3
2
3
2
5
A
B
C
D
DEMO MANUAL DC1717A
Schematic Diagram
dc1717afa
9
DEMO MANUAL DC1717A
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:
This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT
OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete
in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety
measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union
directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.
If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date
of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU
OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims
arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all
appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or
agency certified (FCC, UL, CE, etc.).
No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.
Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and
observe good laboratory practice standards. Common sense is encouraged.
This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
10 Linear Technology Corporation
dc1717afa
LT 0915 REV A • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2013