ADR440ARMZ Analog Devices Inc, ADR440ARMZ Datasheet - Page 16

• Manufacturer Part Number: ADR440ARMZ
• Description: IC VREF LDO XFET 2.048V 8-MSOP
• Manufacturer: Analog Devices Inc
• Series: XFET®r

Specifications of ADR440ARMZ

• Temperature Coefficient: 10ppm/°C
• Reference Type: Series
• Voltage - Output: 2.048V
• Tolerance: ±0.15%
• Voltage - Input: 2.548 ~ 18 V
• Number Of Channels: 1
• Current - Quiescent: 3.75mA
• Current - Output: 10mA
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Topology: Series
• Input Voltage: 3V To 18V
• Reference Voltage: 2.048V
• Reference Voltage Tolerance: 3mV
• Voltage Reference Case Style: MSOP
• No. Of Pins: 8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Cathode: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

ADR440/ADR441/ADR443/ADR444/ADR445
Table 9. Digital Potentiometer Parts
Part No.
AD5251
AD5207
AD5242
AD5262
AD5282
AD5252
AD5232
AD5235
ADN2850
1
Adding a negative supply to the operational amplifier allows
the user to produce a negative programmable reference
by connecting the reference output to the inverting terminal
of the operational amplifier. Choose feedback resistors to
minimize errors over temperature.
PROGRAMMABLE CURRENT SOURCE
It is possible to build a programmable current source using a
setup similar to the programmable voltage source, as shown in
Figure 38. The constant voltage on the gate of the transistor sets
the current through the load. Varying the voltage on the gate
changes the current. This circuit does not require a dual digital
potentiometer.
Can also use a negative supply.
V
0.1µF
CC
No. of
Channels
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
ADR440/
ADR441/
ADR443/
ADR444/
ADR445
GND
Figure 38. Programmable Current Source
V
2
4
IN
V
OUT
6
No. of
Positions
64.00
256.00
256.00
256.00
256.00
256.00
256.00
1024.00
1024.00
0.1µF
AD5259
ITF
I
SPI
I
SPI
I
I
SPI
SPI
SPI
2
2
2
2
C
C
C
C
R (kΩ)
1, 10, 50, 100
10, 50, 100
10, 100, 1M
20, 50, 200
20, 50, 100
1, 10, 50, 100
10, 50, 100
25, 250
25, 250
I
LOAD
R
SENSE
V
(V)
5.5
5.5
5.5
15
15
5.5
5.5
5.5
5.5
Rev. E | Page 16 of 20
DD
1
HIGH VOLTAGE FLOATING CURRENT SOURCE
Use the circuit in Figure 39 to generate a floating current source
with minimal self heating. This particular configuration can
operate on high supply voltages, determined by the breakdown
voltage of the N-channel JFET.
PRECISION OUTPUT REGULATOR
(BOOSTED REFERENCE)
Higher current drive capability can be obtained without
sacrificing accuracy by using the circuit in Figure 40. The
operational amplifier regulates the MOSFET turn-on, forcing
V
increased current drive capability. The circuit allows a 50 mA
load; if higher current drive is required, use a larger MOSFET.
For fast transient response, add a buffer at V
capacitive loading.
O
V
0.1µF
IN
to equal the V
C
IN
ADR440/
ADR441/
ADR443/
ADR444/
ADR445
GND
ADR440/
ADR441/
ADR443/
ADR444/
ADR445
V
2
4
IN
V
Figure 40. Boosted Output Reference
REF
GND
Figure 39. Floating Current Source
OUT
V
2
4
IN
V
. Current is then drawn from V
OUT
6
6
C
0.1µF
OUT
OP90
15V
–V
+V
–V
2N3904
S
S
O
VISHAY
SST111
200Ω
to aid with
2N7002
R
L
IN
, allowing
C
1µF
L
V
O