19-3695; Rev 0; 5/05
10kΩ Precision-Matched
Resistor-Divider in SOT23
MAX5492
General Description
The MAX5492 precision resistor-divider consists of two
accurately matched resistors with access to the ends
and center of the divider. This device offers excellent
resistance matching of 0.035% (A grade), 0.05% (B
grade), and 0.1% (C grade). The MAX5492 includes an
extremely low-resistance-ratio temperature drift of
1.5ppm/°C (typ) over -55°C to +125°C, and has an end-
to-end resistance of 10kΩ. Resistance ratios from 1:1 to
10:1 are available. Five standard ratios are available (see
Table 1), and custom ratios are also available upon
request. To enhance device and system robustness, the
MAX5492 features ±2kV Human Body Model electrostat-
ic discharge (ESD) protection to ensure against real-
world ESD events. The MAX5492 is ideal for precision
gain-setting applications where tight resistance matching
and low temperature drift are necessary.
The MAX5492 is available in a space-saving 5-pin
SOT23 package, and is guaranteed over the military
-55°C to +125°C temperature range.
♦
Resistance Ratios from 1:1 to 10:1
♦
Custom Ratios Available Upon Request
♦
Tight Initial Ratio Accuracy
0.035% (MAX5492A)
0.05% (MAX5492B)
0.1% (MAX5492C)
♦
Low 1.5ppm/°C (typ) Resistor-Ratio-Drift (1.1:1)
♦
Up to 40V Operating Voltage Across Sum of R1
and R2
♦
Tiny 5-Pin SOT23 Package
Features
Applications
Industrial Process Control
Instrumentation
Precision Gain Setting
Medical Equipment
Automatic Test Equipment
Base Stations
PART
Ordering Information*
TEMP
RANGE
RATIO
PIN-
ACCURACY
PACKAGE
(%)
0.035
0.05
0.1
MAX5492
_
A
_ _ _ _ _
-T -55°C to +125°C 5 SOT23-5
MAX5492
_
B
_ _ _ _ _
-T -55°C to +125°C 5 SOT23-5
MAX5492
_
C
_ _ _ _ _
-T -55°C to +125°C 5 SOT23-5
*See
the How to Order section for more details.
Block Diagram
TOP VIEW
MAX5492
P1
R
1
SL
R
2
P2
P3
SH
P1
1
SL
2
P2
3
Pin Configuration
5
SH
MAX5492
4
P3
SOT23
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
10kΩ Precision-Matched
Resistor-Divider in SOT23
MAX5492
ABSOLUTE MAXIMUM RATINGS
Voltage Between P1 and P2 ................................................±50V
Continuous Current into Any Pin......................................±4.2mA
Continuous Power Dissipation (T
A
= +70°C)
5-Pin SOT23 (derate 7.1mW/°C above +70°C).........571.4mW
5-Pin SOT23 (θ
J-A
) .....................................................141°C/W
Operating Temperature Range .........................-55°C to +125°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
DC ELECTRICAL CHARACTERISTICS
(T
A
= -55°C to +125°C, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
Initial Resistor-Ratio Error (Note 2)
SYMBOL
CONDITIONS
MAX5492_A, T
A
= +25°C
MAX5492_B, T
A
= +25°C
MAX5492_C, T
A
= +25°C
Ratio 1.1:1
Resistance-Ratio Temperature
Coefficient (Note 3)
Absolute Temperature Coefficient
of Resistance
Voltage Coefficient of Resistance
End-to-End Resistance (R
1
+ R
2
)
Continuous Working Voltage
Between P1 and P2
P1, P2, P3, SL, SH Capacitance
Resistance-Ratio Stability
-3dB Bandwidth
Thermal Noise
Current Noise
Maximum Power Rating
f
3dB
2000 hours at +70°C
1.1:1 ratio (Note 6)
(Note 7)
(Note 8)
V
P1-P2
Ratio 1.5:1
Ratio 3.2:1
≤
ratio
≤
10:1
TCR
VCR
(Note 4)
(Note 5)
9.25
-40
2
±0.03
30
45
<-30
160
1.5
3
5.5
35
0.1
10
10.75
+40
ppm/°C
ppm/V
kΩ
V
pF
%
MHz
µV
RMS
dB
mW
ppm/°C
MIN
TYP
MAX
±0.035
±0.05
±0.1
%
UNITS
Note 1:
The MAX5492 is 100% production tested at T
A
= +25°C. Specifications over -55°C to +125°C are guaranteed by design
and characterization.
Note 2:
Testing conditions: T
A
= +25°C, V
P1-P2
= 10V and 40V.
Note 3:
Resistance-ratio temperature coefficient is defined
Note 4:
Absolute TCR is defined as
(
R
1
+
∆
(
R
1
+
R
2
)
⎛
R
⎞
∆⎜
1
⎟
⎝
R
2
⎠
R
1
× ∆
T
R
2
and is guaranteed by design, not production tested.
R
2
)
× ∆
T
and is tested at 10V and 40V.
Note 5:
Resistance-ratio voltage coefficient is defined as
⎛
R
⎞
∆⎜
1
⎟
and is guaranteed by design, not production tested.
⎝
R
2
⎠
R
1
× ∆
V
R
2
2
_______________________________________________________________________________________
10kΩ Precision-Matched
Resistor-Divider in SOT23
DC ELECTRICAL CHARACTERISTICS (continued)
(T
A
= -55°C to +125°C, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
Note 6:
Calculate bandwidth by using
MAX5492
R
×
R
2
1
where C is C
P3
and R =
1
.
2πRC
R
1
+
R
2
Note 7:
Calculated according to
kT
noise.
C
Note 8:
In accordance with the military specification MIL-STD-202G method 308.
Typical Operating Characteristics
(V
P1-P3
= 10V, T
A
= +25°C, unless otherwise noted.)
NORMALIZED RESISTANCE-RATIO DRIFT
vs. TEMPERATURE
MAX5492 toc01
NORMALIZED RESISTANCE-RATIO DRIFT
vs. TEMPERATURE
V
P1-P2
= 10V
RATIO = 3.2:1
MAX5492 toc02
200
150
100
RATIO DRIFT (ppm)
V
P1-P2
= 10V
RATIO = 1.1:1
600
400
RATIO DRIFT (ppm)
200
0
-200
-400
-600
50
0
-50
-100
-150
-200
-55
-25
5
35
65
95
125
TEMPERATURE (°C)
-55
-25
5
35
65
95
125
TEMPERATURE (°C)
NORMALIZED RESISTANCE-RATIO DRIFT
vs. TEMPERATURE
MAX5492 toc03
RESISTANCE-RATIO ACCURACY
vs. VOLTAGE
RATIO = 1.1:1
0.03
RATIO ACCURACY (%)
0.02
0.01
0
-0.01
-0.02
-0.03
-0.04
0
5
10
15
20
25
30
35
40
MAX5492 toc04
500
400
300
RATIO DRIFT (ppm)
200
100
0
-100
-200
-300
-400
-55
-25
5
35
65
95
V
P1-P2
= 10V
RATIO = 10:1
0.04
125
TEMPERATURE (°C)
VOLTAGE (V)
_______________________________________________________________________________________
3
10kΩ Precision-Matched
Resistor-Divider in SOT23
MAX5492
Typical Operating Characteristics (continued)
(V
P1-P3
= 10V, T
A
= +25°C, unless otherwise noted.)
FREQUENCY RESPONSE
MAX5492 toc05
SPECTRAL NOISE DENSITY
MAX5492 toc06
TOTAL HARMONIC DISTORTION
PLUS NOISE RESPONSE
RATIO = 1.1:1
20Hz TO 20kHz BANDPASS
MAX5492 toc07
6
3
0
RESPONSE (dB)
RATIO = 1.1:1
C
L
= 10pF
100
RATIO = 1.1:1
100
10
1
-6
-9
-12
-15
-18
0.1
1
10
100
1000 10,000 100,000
FREQUENCY (kHz)
V
P1-P2
= 10V
V
P1-P2
= 2V
THD+N (%)
1000
-3
NOISE (nV/
√
Hz)
0.1
0.01
0.001
10
1
10
100
FREQUENCY (Hz)
0.0001
10
100
1k
FREQUENCY (Hz)
10k
100k
Pin Description
PIN
1
2
3
4
5
NAME
P1
SL
P2
P3
SH
R1 Connection Terminal
Sense Connection for Low Side of Resistor String. Leave floating or connect in a Kelvin connection
configuration.
R2 Connection Terminal
Set-Point Connection Terminal
Sense Connection for High Side of Resistor String. Leave floating or connect in a Kelvin connection
configuration.
FUNCTION
Detailed Description
The MAX5492 consists of two precision, low-ratio-drift
resistors with an end-to-end resistance of 10kΩ (R
1
+ R
2
).
(See Figure 1.) P3 is the set point of the divider. The
maximum working voltage of the MAX5492 is 40V.
This device offers a wide range of resistance ratios
(R
1
/R
2
) from 1:1 to 10:1 and is ideally suited for preci-
sion operational-amplifier gain/attenuation control. The
MAX5492 features a ±2kV ESD protection that
enhances system robustness. A maximum initial ratio
accuracy of 0.035% and a low ratio drift enhance sys-
tem accuracy.
Applications Information
Kelvin Sensing
Kelvin sensing can improve accuracy in sensitive appli-
cations. Apply a voltage or current at P1 and use sense
high (SH) and sense low (SL) to monitor the voltage at
the upper and lower ends of the resistor string.
4
_______________________________________________________________________________________
10kΩ Precision-Matched
Resistor-Divider in SOT23
Typical Applications
A
=
V
OUT
R
= −
1
V
IN
R
2
OUT
IN
A
=
V
OUT
R
=
1
+
1
V
IN
R
2
OUT
MAX5492
P3
P3
P2
IN
R
2
R
1
MAX5492
P1
P2
R
2
R
1
MAX5492
P1
Figure 1. Inverting Amplifier Configuration
IN
A
=
V
OUT
R
2
=
V
IN
R
1
+
R
2
Figure 2. Noninverting Amplifier Configuration
IN
P1
A
=
V
OUT
R
2
=
V
IN
R
1
+
R
2
P1
MAX5492
R
1
MAX5492
R
1
P3
OUT
R
2
R
2
P3
OUT
P2
P2
Figure 3. Buffered Attenuator
Figure 4. Attenuator with Buffer
Self-Heating and Error
Applying a voltage across terminals P1 and P2 causes
the device to heat up due to power dissipation. In high-
voltage applications, consider the error in resistance-
ratio temperature coefficient caused by self-heating.
The worst-case self-heating occurs when the operating
voltage attains its maximum value. Approximate the
result of power dissipation under this condition as:
P
DISS
=
The thermal resistance from junction to ambient,
θ
J-A
,
for a 5-pin SOT23 package is 141°C/W. Calculate the
resulting temperature rise as:
∆T
= 160mW x 141°C/W = 22.5°C
If the ratio temperature coefficient is 1.5ppm/°C (typ),
the total error introduced by self-heating is:
22.5°C x 1.5ppm/°C = 33.75ppm
(
V
MAX
)
2
R
=
(
40V
)
2
10k
Ω
=
160mW
_______________________________________________________________________________________
5
