Corporate Office
1717 Chicago Avenue
Riverside, California 92507-2364
Phone: (951) 788-1700
Fax: (951) 369-1151
Applications Engineering and Sales
17271 North Umpqua Hwy.
Roseburg, Oregon 97470-9422
Phone: (541) 496-0700
Fax: (541) 496-0408
© 2012 Caddock Electronics, Inc.
IL-140.0213
e-mail: caddock@caddock.com • web: www.caddock.com
For Caddock Distributors listed by country see caddock.com/contact/dist.html
Type USGS - Ultra-Stable Selected Resistor
Sets are designed for use in high voltage
systems that require excellent temperature
stability and long term stability. The resistors
used in these Selected Resistor Sets are
manufactured with Caddock’s Tetrinox®
Resistance Film System.
The individual USG Style resistors that form
these Ultra-Stable Selected Resistor Sets are
individually characterized using automated
data acquisition systems, and then selected
to form a Set Resistance with an Absolute
Temperature Coefficient (TC) of 5 ppm/°C
maximum.
The low Voltage Coefficient (VC) of the
USG1110 Style resistors used in these
selected resistor sets achieves excellent
stability over the operating voltage range.
Multiple USGS Selected Resistor Sets can
be used in series to form a string of resistors
that achieves a higher total resistance and a
higher voltage rating with 5 ppm/°C overall
temperature coefficient.
For Custom Selected Resistor Sets contact
Applications Engineering.
Type USGS High Voltage, Ultra-Stable,
Total Set Resistance up to 500 Megohm with
Absolute TC of 5 ppm/°C
Voltage Ratings up to 50 kV DC - Custom Selected Resistor Sets Available
Low TC Selected Resistor Sets
Model Number
Set
Schematic
USGS-3-1110-300M-B5
USGS-5-1110-500M-B5
30 kV DC
50 kV DC
3
5
300 Megohm
500 Megohm
5 ppm/°C
5 ppm/°C
0.03 ppm/V
0.02 ppm/V
Fig. 1A
Fig. 1B
0.10%
0.10%
Operating
Voltage
1
Number of
Resistors
2
Set
Resistance
3
Set
Tolerance
4
Set
TC
5
Set
VC
6
High Voltage Design Note: The specifications for these high voltage resistor sets are based upon the proper high voltage field stress
management, thermal design, and material selection for the housing which encloses the high voltage resistor set. The design of the
housing is the responsibility of the user. These resistors are compatible with many high voltage potting materials, but issues regarding
potting material adhesion, bubble free potting, and electrical insulation/isolation are the responsibility of the user.
Dielectric Absorption:
The USG resistors are engineered by Caddock to minimize dielectric absorption. The circuit board, potting, or
encapsulation materials that are in contact with, or in circuit with the USG resistors, can exhibit dielectric absorption behavior that can
affect the performance of the circuit. The user is responsible for the selection of materials and the design so that dielectric absorption
and its effects on the performance of the circuit are minimized.
Resistor Style
Resistance
Tolerance
TC
USG1110
100 Meg
±0.20%
±20 ppm/°C
Figure 2 and Table:
Physical Dimensions and Specifications of the
individual USG1110 Style Resistors that form USGS Selected Resistor Sets
0.350
±
.040
(8.89
±
1.02)
2.000 ± .080
(50.80
±
2.03)
1.500
±
.125
(38.10
±
3.18)
.040
±
.002
(1.02
±
.05)
USG1110
Figure 1A:
Schematic of the three 100 Megohm USG1110 Style resistors in a
USGS-3-1110-300M-B5 Selected Resistor Set, which are connected in series to
form the 300 Megohm Resistance.
Figure 1B:
Schematic of the five 100 Megohm USG1110 Style resistors in a
USGS-5-1110-500M-B5 Selected Resistor Set, which are connected in series to
form the 500 Megohm Resistance.
100 Meg
100 Meg
100Meg
= 300 Meg
= 500 Meg
100 Meg
100 Meg
100 Meg
100 Meg
100 Meg
Specifications for the Selected Resistor Sets
:
All specifications are valid for the Set Resistance, which is
formed by the series connection of the resistors in the Selected
Resistor Set.
Operating Voltage:
The maximum continuous operating
voltage for the set of resistors connected in series.
Number of Resistors:
The number of resistors in each
Selected Resistor Set, described by the Caddock Part
Number.
Set Resistance:
The total resistance of the set of resistors
connected in series.
Set Tolerance:
The Tolerance of the Set Resistance,
measured at low voltage (DC) at +23°C ±2°C.
Set TC: The Temperature Coefficient of the Set Resistance,
measured at +10°C and +50°C, ref. to +25°C.
Set VC: The Voltage Coefficient of the Set Resistance,
measured at 10% and 100% of the Operating Voltage.
1
2
3
4
5
6
New
Storage Temperature Range: -35°C to +85°C.