DEMO CIRCUIT 1 1 1 6
LTC6103
Q UICK S TA RT G UIDE
L TC6 1 0 3
Du a l, H ig h V o lta g e , H ig h S id e
Cu rre n t S e n s e A m p lifie r
currents through l
oad resistances, ground-l
oop errors
can be el
iminated by simpl l
y ocating the l resistors at
oad
the destination point (subsequent signalprocessing such
as A/ conversion). Remote l
D
oading can be eval
uated by
simpl removing the on board l resistors (R3 and R6).
y
oad
The key perf
ormance characteristics of the LTC6103 and
DC1116 are show n in the Perf
ormance Summary bel .
ow
Design files for this circuit board are available. Call the
LTC factory.
L
, LT, Over-The-Top are registered trademarks ofLinear Technol Corporation. Other
ogy
product names may be trademarks ofthe companies that manuf
acture the products.
DESCRIPTION
Demonstration Circuit 1116 is a Dual High Vol
,
tage, High
Side Current Sense Ampl ier f
if eaturing the LTC6103.
This demo board provides tw o independent circuits that
each ampl y a current-sense resistor vol
if
tage-drop, and
provide precision uni-pol output vol
ar
tages proportional
to the respective l currents. The demo circuit incl
oad
udes
scal resistors that program the gain of the circuits to
ing
V.
rom the
25V/ Each section of the LTC6103 is pow ered f
same suppl that the sense resistor is connected to and
y
provides a ground ref
erenced output. Each section of the
y perf
orm current
LTC6103 can independentl
measurements on suppl ranging f
ies
rom 4V to 60V.
Since the output vol
tages are devel
oped as controled
l
PERF ORM ANCE SU M M ARY
SYM BOL
V
INA
, V
INB
V
MonA
V
MonB
I
MonA
I
MonB
I
OUTA
, I
OUTB
I
INAQ
I
INBQ
t
R
PARAM ETER
Monitored Suppl Input Range
y
Measurement Output Signal
Measurement Output Signal
Measurement Output Signal(current mode)
Measurement Output Signal(current mode)
Output Load Current Range
V
INA
Quiescent Current
V
INB
Quiescent Current
V
MonA
or V
MonB
step-response time
Specifications are at T
A
= 25°C
CONDI ONS
TI
I
OUTA
= 5A
I
OUTB
= 5A
I
OUTA
= 5A, R3 removed
I
OUTB
= 5A, R6 removed
Thermall ofR
SENSE
(R1 or R4)
imit
V
INA
=12V, I
OUTA
= 0A
V
INB
=12V, I
OUTB
= 0A
I
OUTA
or I
OUTB
step f 0A to 5A
rom
MI
N
4
TYP
5… 48
2.5
2.5
500
500
250
250
2
M AX
60
UNI
TS
V
V
V
µA
µA
A
µA
µA
µs
7
OPERATING PRINCIPL ES
The LTC6103 operates by ampl ying the vol
if
tage drop on
a sense resistor pl
aced in series w ith the pow er source of
a l to be monitored. The sense inputs of the ampl ier
oad
if
diferentialy measure the sense-resistor drop to control
f
l
an internalvariabl current source that alow s transl
e
l
ation
of the input inf
ormation to a l
evel ref
erenced to V
EE
(ground in this demo circuit). The LTC6103 provides tw o
identical sense ampl iers in one package. In DC1116 as
if
shipped, the sense resistors instaled are 20mΩ and the
l
other resistors program the gains to 25V/ so the
V,
nominal output scal
ings are 500mV per ampere of l
oad
current. Other scal
ings can be real
ized by making
resistor changes on the demo circuit.
The DC1116 Schematic diagram is show n in Figure 2.
1
LTC6103
Q U ICK START PROCEDU RE
Demonstration circuit 1116 is easy to set up to eval
uate
the perf
ormance of the LTC6103. Ref to Figure 1 f
er
or
proper measurement equipment setup and f l the
olow
procedure bel :
ow
NOTE.
Each section ofthe LTC6103 may be pow ered (or not)
independentl
y.
4.
Turn on the pow er suppl
y.
5.
Measure an output vol
tage that corresponds to the
l current. V
MonA
= 0.5×I
OUT
f the f
oad
or
actory instaled
l
resistors.
6.
W ith pow er of , connect a second pow er suppl
f
y
positive to INB and the common to GND. This suppl
y
shoul be in the range of4V to 60V.
d
7.
Connect a second vol
tmeter or osciloscope probe to
l
the MonB terminal w ith the common connection or
,
ground cl tied to GND.
ip
8.
Connect a second l to the OUTB terminal(positive)
oad
and return (negative) to the common of the second
pow er suppl
y.
9.
Turn on the second pow er suppl
y.
10.
Measure an output vol
tage that corresponds to the
second l current. V
MonB
= 0.5×I
OUT
f the f
oad
or
actory
instaled resistors.
l
NOTE.
A dif erentialmeasurement betw een MonA and MonB w il refect the
f
l l
dif erence in l current in the tw o paths. This is usef in measuring l
f
oad
ul
oad
current in H-bridge appl
ications.
1.
W ith pow er of, connect a pow er suppl positive to
f
y
INA and the common to GND. This suppl shoul be
y
d
in the range of 4V to 60V. If this suppl is not
y
equipped w ith an accurate current readout, a DMM
(set to measure Amperes) may be connected in series
w ith the suppl
y.
NOTE.
Be sure that the capacity ofa current measuring DMM is adequate
to handl the intended l current.
e
oad
2.
Connect a vol
tmeter or osciloscope probe to the
l
MonA terminal w ith the common connection or
,
ground cl tied to GND.
ip
3.
Connect a l to the OUTA terminal (positive) and
oad
return (negative) to the common of the pow er suppl
y.
The l
oad may be a pow er resistor, active l
oad
instrument, or other circuit ofinterest.
POWER
SUPPLY
POWER
SUPPLY
+ COM
+ COM
DMM
A COM V
LOAD
A
(10Ω)
LOAD
B
(10Ω)
DMM
A COM V
Figure 1. Proper M easurem ent Equipm ent Setup
2
Embedded System
京公网安备 11010802033920号
EEWORLD
