INTERSIL X60008B-25

X60008B-25, X60008C-25, X60008D-25
®
Data Sheet
March 15, 2005
Precision 2.5V FGA™ Voltage Reference
FN8140.0
DESCRIPTION
The X60008-25 FGA™ voltage references are very
high precision analog voltage references fabricated in
Intersil’s proprietary Floating Gate Analog technology,
which achieves superior levels of performance when
compared to conventional band gap, buried zener, or
XFET™ technologies.
FEATURES
• Output Voltage: 2.500V
• Absolute Initial Accuracy Options:
±0.5mV & ±1.0mV
• Ultra Low Power Supply Current: 500nA
FGA™ voltage references feature very high initial
accuracy, very low temperature coefficient, excellent
long term stability, low noise and excellent line and
load regulation, at the lowest power consumption
currently available. These voltage references enable
advanced applications for precision industrial &
portable systems operating at significantly higher
accuracy and lower power levels than can be achieved
with conventional technologies.
• Low Temperature Coefficient options:
3, 5 & 10ppm/°C
• 10 mA Source & Sink Current Capability
• 10 ppm/1000hrs Long Term Stability
• Supply Voltage Range: 4.5V to 6.5V
• 5kV ESD (Human Body Model)
• Standard Package: SOIC-8
• Temp Range: -40°C to +85°C
APPLICATIONS
• High Resolution A/Ds & D/As
• Precision Current Sources
• Smart sensors
• Digital Meters
• Precision Regulators
• Strain Gage Bridges
• Calibration Systems
• Precision Oscillators
• Threshold Detectors
• V-F Converters
• Battery Management Systems
• Servo Systems
TYPICAL APPLICATION
VIN = +5.0V
0.1µF
10µF
VIN
VOUT
X60008-25
0.001µF(*)
GND
REF IN
Serial
Bus
Enable
SCK
SDAT
16 to 24-bit
A/D Converter
(*)Also see Figure 3 in Applications Information
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
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X60008B-25
PACKAGE DIAGRAM
X60008-XX
SOIC
GND
1
8
DNC
VIN
2
7
DNC
DNC
3
6
VOUT
GND
4
5
DNC
PIN CONFIGURATIONS
Pin Name
GND
VIN
Description
Ground Connection
Power Supply Input Connection
VOUT
Voltage Reference Output Connection
DNC
Do Not Connect; Internal Connection – Must Be Left Floating
ORDERING INFORMATION
X 60008 C I S8 – 25
Logo
Device Part Number
60008 = Standard
Grade
B = ±0.5 mV, 3 ppm/°C
C = ±0.5 mV, 5 ppm/°C
D = ±1.0 mV, 10 ppm/°C
2
Temperature Range
I = -40°C to +85°C
Package
S8 = 8 lead SOIC
VOUT Option
25 = 2.500V
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March 15, 2005
X60008B-25
ABSOLUTE MAXIMUM RATINGS
COMMENT
Storage Temperature Range..................-65°C to +125°C
Max Voltage Applied VIN to Gnd ............... -0.5V to +6.5V
Max Voltage Applied VOUT to Gnd(*) ........ -0.5V to +3.5V
Voltage on “DNC” pins......... No connections permitted to
these pins.
Lead Temperature, soldering(*) ...........................+ 225°C
Absolute Maximum Ratings are limits which may result
in impaired reliability and/or permanent damage to the
device. These are stress ratings provided for information only and functional operation of the device at
these or any other conditions beyond those indicated
in the operational sections of this specification are not
implied.
(*) note: maximum duration = 10 seconds
For guaranteed specifications and test conditions, see
Electrical Characteristics.
RECOMMENDED OPERATING CONDITIONS
Temperature
Min.
Max.
Industrial
-40°C
+85°C
The guaranteed specifications apply only for the test
conditions listed. Some performance characteristics
may degrade when the device is not operated under
the listed test conditions.
ELECTRICAL CHARACTERISTICS
(Operating Conditions: VIN = 5.0V, IOUT = 0mA, COUT = 0.001µF, TA = -40 to +85°C unless otherwise specified.)
Symbol
Parameter
VOUT
Output Voltage
VOA
VOUT Accuracy
X60008B-25
X60008C-25
X60008D-25
IIN
Supply Current
VIN
Input Voltage Range
TC VOUT
Output Voltage
Temperature Coefficient(1)
∆VOUT/∆VIN
Conditions
Min
Typ
Max
2.500
Units
V
TA = 25°C
mV
-0.50
-0.50
-1.00
+0.50
+0.50
+1.00
800
nA
6.5
V
X60008B-25
X60008C-25
X60008D-25
3
5
10
ppm/°C
Line Regulation
+4.5V ≤ VIN ≤ +6.5V
100
µV/V
∆VOUT/∆IOUT
Load Regulation
0mA ≤ ISOURCE ≤ 10mA
-10mA ≤ ISINK ≤≤ 0mA
10
20
40
80
µV/mA
∆VOUT/∆t
Long Term Stability
TA = 25°C
10
ppm/
1000Hrs
∆VOUT/∆TA
Thermal Hysteresis(2)
∆T = -40°C to +85°C
50
ppm
ISC
Short Circuit Current(3)
TA = 25°C
50
VN
Output Voltage Noise
0.1Hz to 10Hz
30
Note:
500
4.5
80
mA
µVpp
1. Over the specified temperature range. Temperature coefficient is measured by the box method whereby the change in VOUT is divided
by the temperature range; in this case, -40°C to +85°C = 125°C.
2. Thermal Hysteresis is the change in VOUT created by package stress @ TA = 25°C after temperature cycling. VOUT is read initially at
TA = 25°C; the X60008 is then cycled between Hot (85°C) and Cold (-40°C) before a second VOUT measurement is taken at 25°C. The
deviation between the initial VOUT reading and the second VOUT reading is then expressed in ppm.
3. Guaranteed by device characterization and/or correlation to other device tests.
3
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TYPICAL PERFORMANCE CHARACTERISTIC CURVES
(VIN = 5.0V, IOUT = 0mA, TA = 25°C unless otherwise specified)
LINE REGULATION
80
VOUT (V)
(normailized to 2.5V at VIN = 5V)
60
DELTA VO (µV)
(normailized to VIN = 5.00V)
LINE REGULATION
2.50008
40
20
0
-20
-40°C
+25°C
-40
+85°C
-60
-80
-100
4.5
5
5.5
6
6.5
310nA
520nA
690nA
2.50006
2.50004
2.50002
2.5
2.49998
2.49996
2.49994
4.5
5
5.5
6
6.5
VIN (V)
VIN (V)
0.1Hz to 10Hz VOUT NOISE
Band Pass Filter with 1 zero at .1Hz and 2 poles at 10 Hz
LOAD REGULATION
0.7
0.6
0.4
0.3
0.2
+25°C
10µV/div
DELTA VOUT (mV)
0.5
-40°C
0.1
0.0
+85°C
-0.1
-0.2
-0.3
-20
-15
-10
-5
SINKING
0
5
10
15
SOURCING
1 Sec/div
20
IOUT (mA)
VOUT vs TEMPERATURE
Normalized to 25°C
2.502
PSRR vs CAP Load
0
No Load
-10
1nF Load
-20
2.501
-30
520nA
-40
PSRR (dB)
VOUT (V)
690nA
2.5
320nA
10nF
Load
-50
-60
-70
100nF Load
2.499
-80
-90
-100
2.498
-40
-15
10
35
TEMPERATURE (°C)
4
60
85
1
10
100
1000
10000
100000
1000000
FREQUENCY (Hz)
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March 15, 2005
X60008B-25
TYPICAL PERFORMANCE CHARACTERISTIC CURVES
(VIN = 5.0V, IOUT = 0mA, TA = 25°C unless otherwise specified)
50µA LOAD TRANSIENT RESPONSE
10mA LOAD TRANSIENT RESPONSE
CL = .001µF
∆I IN = -10mA
∆I IN = +10mA
100mV/DIV
500mV/DIV
CL = .001µF
∆IIN = -50µA
∆I IN = +50µA
1mS/DIV
500µSEC/DIV
LINE TRANSIENT RESPONSE
LINE TRANSIENT RESPONSE
200mV/DIV
CL = .001µF
200mV/DIV
CL = 0
∆VIN = -500mV
∆VIN = +500mV
500µSEC/DIV
5
∆VIN = -500mV
∆VIN = +500mV
500µSEC/DIV
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March 15, 2005
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TYPICAL PERFORMANCE CHARACTERISTIC CURVES
(VIN = 5.0V, IOUT = 0mA, TA = 25°C unless otherwise specified)
ZOUT vs FREQUENCY
300
250
580
no Load
1nF Load
-40°C
+25°C
+85°C
560
10nF Load
150
I IN (nA)
200
ZOUT (Ω)
IIN vs VIN
600
540
520
100
500
50
100nF Load
480
4.5
0
100
10
100
1000
10000
100000
5
5.5
6
6.5
VIN (V)
FREQUENCY (Hz)
IIN vs VIN
TURN-ON TIME
800
6
3 units representative of IIN Range
700
VIN
5
VIN & VOUT (V)
600
I IN (nA)
500
400
300
4
3
VOUT
2
200
1
100
0
4.5
0
5
5.5
VIN (V)
6
6
6.5
-1
1
3
5
7
9
11
TIME (mSec)
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X60008B-25
APPLICATIONS INFORMATION
FGA Technology
The X60008 series of voltage references use the floating gate technology to create references with very low
drift and supply current. Essentially the charge stored
on a floating gate cell is set precisely in manufacturing.
The reference voltage output itself is a buffered version of the floating gate voltage. The resulting reference device has excellent characteristics which are
unique in the industry: very low temperature drift, high
initial accuracy, and almost zero supply current. Also,
the reference voltage itself is not limited by voltage
bandgaps or zener settings, so a wide range of reference voltages can be programmed (standard voltage
settings are provided, but customer-specific voltages
are available).
The process used for these reference devices is a
floating gate CMOS process, and the amplifier circuitry
uses CMOS transistors for amplifier and output transistor circuitry. While providing excellent accuracy,
there are limitations in output noise level and load regulation due to the MOS device characteristics. These
limitations are addressed with circuit techniques discussed in other sections.
Nanopower Operation
Reference devices achieve their highest accuracy
when powered up continuously, and after initial stabilization has taken place. This drift can be eliminated by
leaving the power-on continuously.
The X60008 is the first high precision voltage reference
with ultra low power consumption that makes it possible
to leave power-on continuously in battery operated circuits. The X60008 consumes extremely low supply current due to the proprietary FGA technology. Supply
current at room temperature is typically 500nA which is
1 to 2 orders of magnitude lower than competitive
devices. Application circuits using battery power will
benefit greatly from having an accurate, stable reference which essentially presents no load to the battery.
In particular, battery powered data converter circuits
that would normally require the entire circuit to be disabled when not in use can remain powered up
between conversions as shown in figure 1. Data acquisition circuits providing 12 to 24 bits of accuracy can
operate with the reference device continuously biased
with no power penalty, providing the highest accuracy
and lowest possible long term drift.
Other reference devices consuming higher supply currents will need to be disabled in between conversions
to conserve battery capacity. Absolute accuracy will
7
suffer as the device is biased and requires time to settle to its final value, or, may not actually settle to a final
value as power-on time may be short.
Figure 1.
VIN = 4.5V to 6.5V
10µF
0.01µF
VIN
VOUT
X60008-25
GND
0.001µF
REF IN
Serial
Bus
Enable
SCK
SDAT
12 to 24-bit
A/D Converter
Board mounting Considerations
For applications requiring the highest accuracy, board
mounting location should be reviewed. Placing the
device in areas subject to slight twisting can cause
degradation of the accuracy of the reference voltage
due to die stresses. It is normally best to place the
device near the edge of a board, or the shortest side,
as the axis of bending is most limited at that location.
Obviously mounting the device on flexprint or
extremely thin PC material will likewise cause loss of
reference accuracy.
Noise Performance and Reduction:
The output noise voltage in a 0.1Hz to 10Hz
bandwidth is typically 30µVp-p. This is shown in the
plot in the Typical Performance Curves. The noise
measurement is made with a bandpass filter made of
a 1 pole high-pass filter with a corner frequency at
.1Hz and a 2-pole low-pass filter with a corner
frequency at 12.6Hz to create a filter with a 9.9Hz
bandwidth. Noise in the 10KHz to 1MHz bandwidth is
approximately 400µVp-p with no capacitance on the
output, as shown in Fig. 2 below. These noise
measurements are made with a 2 decade bandpass
filter made of a 1 pole high-pass filter with a corner
frequency at 1/10 of the center frequency and 1-pole
low-pass filter with a corner frequency at 10 times the
center frequency. Figure 2 also shows the noise in the
10KHz to 1MHz band can be reduced to about 50µVpp using a .001µF capacitor on the output. Noise in the
1KHz to 100KHz band can be further reduced using a
0.1µF capacitor on the output, but noise in the 1Hz to
100Hz band increases due to instability of the very low
power amplifier with a 0.1µF capacitance load. For
FN8140.0
March 15, 2005
X60008B-25
load capacitances above .001µF the noise reduction
network shown in fig. 3 is recommended. This network
reduces noise sig-nificantly over the full bandwidth. As
shown in fig. 2, noise is reduced to less than 40µVp-p
from 1Hz to 1MHz using this network with a .01µF
capacitor and a 2kΩ resistor in series with a 10µF
capacitor.
Figure 2.
X60008-25 NOISE REDUCTION
Turn-On Time
The X60008 devices have ultra-low supply current and
thus the time to bias up internal circuitry to final values
will be longer than with higher power references. Normal turn-on time is typically 7ms. This is shown in the
graph, Figure 4. Since devices can vary in supply current down to 300nA, turn-on time can last up to about
12ms. Care should be taken in system design to
include this delay before measurements or conversions are started.
400
CL = .001µF
CL = .1µF
300
CL = .01µF & 10µF + 2kΩ
X60008 TURN-ON TIME (25°C)
6
250
VIN
5
200
150
VIN & VOUT (V)
NOISE VOLTAGE (µVp-p)
Figure 4.
CL = 0
350
100
50
4
690 nA
3
VOUT
2
0
1
10
100
1000
10000
100000
520 nA
320 nA
1
Figure 3.
0
VIN = 6.5V
-1
10µF
.1µF
1
3
VO
X60008-25
7
9
Temperature Coefficient
GND
2kΩ
.01µF
10µF
8
5
TIME (mSec)
VIN
The limits stated for temperature coefficient (tempco)
are governed by the method of measurement. The
overwhelming standard for specifying the temperature
drift of a reference is to measure the reference voltage
at two temperatures, take the total variation, (VHIGH VLOW), and divide by the temperature extremes of
measurement (THIGH - TLOW). The result is divided by
the nominal reference voltage (at T = 25°C) and multiplied by 106 to yield ppm/°C. This is the “Box” method.
FN8140.0
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X60008B-25
TYPICAL APPLICATION CIRCUITS
Precision 2.5V, 50mA Reference.
VIN = 5.2V to 6.5V
R = 200Ω
2N2905
VIN
X60008-25
VOUT
2.5V/50mA
0.009µF
GND
Kelvin Sensed Load
5.0V
0.1µF
VIN
VOUT
+
X60008-25
VOUT Sense
–
Load
GND
2.5V Full Scale Low-Drift 10-bit Adjustable Voltage Source
4.5V to 6.5V
0.1µF
VIN
VOUT
X60008-25
GND
0.01µF
VCC RH
X9119
2-Wire Bus
SDA
+
SCL
–
VSS
9
VOUT
VOUT
(buffered)
RL
FN8140.0
March 15, 2005
X60008B-25
PACKAGING INFORMATION
8-Lead Plastic, SOIC, Package Code S8
0.150 (3.80)
0.158 (4.00)
0.228 (5.80)
0.244 (6.20)
Pin 1 Index
Pin 1
0.014 (0.35)
0.019 (0.49)
0.188 (4.78)
0.197 (5.00)
(4X) 7°
0.053 (1.35)
0.069 (1.75)
0.004 (0.19)
0.010 (0.25)
0.050 (1.27)
0.010 (0.25)
X 45°
0.020 (0.50)
0.050" Typical
0.050"
Typical
0° - 8°
0.0075 (0.19)
0.010 (0.25)
0.250"
0.016 (0.410)
0.037 (0.937)
FOOTPRINT
0.030"
Typical
8 Places
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)
All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems.
Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without
notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
10
FN8140.0
March 15, 2005