2
AN1339.0
July 23, 2007
User-selectable Options
(Figure 3)
Component pads are included to enable a variety of
user-selectable circuits to be added to the amplifier inputs,
the VREF input, and the amplifier feedback loops. A voltage
divider and filter option can be added to establish a power
supply-tracking common mode reference at the VREF input.
The inverting and non-inverting inputs have additional
resistor placements for adding input attenuation, or to
establish input DC offsets through the VREF pin.
.
RREFA-
RINA2-
RREFA+
RINA+
RINA-
RGA+
RINA1+
OPEN
5
DN
P
DN
P
IN-A
DNP
DN
P
J6
1
2
3
4
C7
1
2
R21
R15
J5
1
2
3
4
5
R2
R1
1
1
2
0
R2
0
IN+A
100K
R24
OPEN
C6
R6
0
R28
DNP
R14
10K
R5
10K
RREF
4.
7U
F
10K
0
R33
C5
1
2
R3
2
J4
1
REF1
IN(A,B,C,D)-
IN(A,B,C,D)+
FIGURE 3. COMPONENT-SELECTABLE OPTIONS
ISL284xxEVAL1Z Components Parts List
DEVICE NUMBER
DESCRIPTION
COMMENTS
C1, C2, C5
CAP-TANTALUM, SMD, D, 4.7µF, 50V, 10% LOW ESR, ROHS
Power Supply Decoupling
C3, C4
CAP, SMD, 0603, 0.1µF, 25V, 10%, X7R, ROHS
Power Supply Decoupling
C6-C25
CAP, SMD, 0603, DNP-PLACE HOLDER, ROHS
User selectable capacitors - not
populated
D1, D2
DIODE-RECTIFIER, SMD, SOD-123, 2P, 40V, 0.5A, ROHS
Reverse Power Protection
U1 (ISL28476EVAL1Z)
ISL28476FAZ, IC-RAIL-TO-RAIL PRECISION OP AMP, 16P, QSOP, ROHS
U1 (ISL28478EVAL1Z)
ISL28478FAZ, IC-RAIL-TO-RAIL PRECISION OP AMP, 16P, QSOP, ROHS
U1 (ISL28486EVAL1Z)
ISL28486FAZ, IC-RAIL-TO-RAIL PRECISION OP AMP, 16P, QSOP, ROHS
U1 (ISL28488EVAL1Z)
ISL28488FAZ, IC-RAIL-TO-RAIL PRECISION OP AMP, 16P, QSOP, ROHS
R2-R4, R11-R13, R20-R23, R25,
R26, R28, R30, R31, R34, R38,
R42, R43, R46, R55-R58,
R59-R62
RESISTOR, SMD, 0603, 0.1%, MF, DNP-PLACE HOLDER
User selectable resistors - not
populated
R6, R8, R10, R15, R17, R19, R36,
R41, R51-R54, R63-R66
RES, SMD, 0603, 0
Ω
, 1/16W,TF, ROHS
0
Ω
user selectable resistors
R5, R7, R9, R14, R16, R18, R33,
R35, R40, R67-R70
RES, SMD, 0603, 10k, 1/10W, 1%, TF, ROHS
RG gain resistors
R24, R27, R29, R39, R45, R47,
R49, R50
RES, SMD, 0603, 100k, 1/10W, 1%, TF, ROHS
RF gain resistors
R1, R32, R37, R44, R48
RES, SMD, 0805, 0
Ω
, 1/8W, TF, ROHS
0
Ω
user selectable resistors
Application Note 1339
