Document Outline
- Return to Contents
- TCN4040
- List of Figures
- Features
- Applications
- Ordering Information
- Pin Configurations
- General Description
- Absolute MaximumRatings
- Operating Ratings (Notes 1 and 2)
- Electrical Characteristics
- Pin Description
- Applications Information
- TCN4041
- List of Figures
- 1. Shunt Regulator
- 2. Adjustable Shunt
- Features
- Applications
- Ordering Information
- General Description
- Absolute Maximum Ratings
- Operating Ratings (Notes 1 and 2)
- Electrical Characteristics
- Pin Configuration
- Pin Description
- Applications Information
TCN4040
1
PRELIMINARY INFORMATION
TCN4040-01 6/16/97
PRECISION MICROPOWER
SHUNT VOLTAGE REFERENCE
TCN4040
FEATURES
s
Small Packages ....... SOT-23B-3, TO-92, and SO-8
s
Output Capacitor Not Required
s
Handles Capacitive Loads
s
Fixed Reverse Breakdown Voltage of 2.5V
s
Low Output Noise
s
Wide Operating Current Range (60
A to 15mA)
s
40
C to + 85
C Operating Temperature Range
APPLICATIONS
s
Portable, Battery-Powered Equipment
s
Data Acquisition Systems
s
Instrumentation
s
Process Control
s
Energy Management
s
Product Testing
s
Automotive
s
Precision Audio Components
PRECISION MICROPOWER SHUNT VOLTAGE REFERENCE
TelCom Semiconductor reserves the right to make changes in the circuitry and specifications to its devices.
GENERAL DESCRIPTION
For applications in tight quarters, the TCN4040 preci-
sion voltage reference is available in a space-saving
3mm x 1.3mm SOT-23B-3 surface mount package. The
TCN4040 eliminates the need for an external stabilizing
capacitor while maintaining stability with any capacitive
load. The minimum operating current is 60
A. The maxi-
mum operating current is 15mA.
To ensure that the prime parts have an accuracy of
better than
0.5% (C grade) at 25
C, the TCN4040 uses
fuse and zener-zap reverse breakdown voltage trim during
wafer sort. Low dynamic impedance and bandgap reference
temperature drift curvature correction maintain stable re-
verse breakdown voltage accuracy over a wide range of
operating temperatures ( 40
C to + 85
C) and currents
from (60
A to 15mA).
The TCN4040 also is available in both adjustable and
1.2V versions.
ORDERING INFORMATION
Output
Voltage Tolerance
Part No.
Voltage (V)
Package
Temp. Coefficient Grade
TCN4040C-2.5ENB
2.5
SOT-23B-3*
0.5%, 100ppm/
C Max (C Grade)
TCN4040C-2.5EOA
2.5
8-Pin SOIC
0.5%, 100ppm/
C Max (C Grade)
TCN4040C-2.5EZB
2.5
TO-92
0.5%, 100ppm/
C Max (C Grade)
TCN4040D-2.5EOA
2.5
8-Pin SOIC
1.0%, 150ppm/
C Max (D Grade)
TCN4040D-2.5ENB
2.5
SOT-23B-3*
1.0%, 150ppm/
C Max (D Grade)
TCN4040D-2.5EZB
2.5
TO-92
1.0%, 150ppm/
C Max (D Grade)
TCN4040E-2.5ENB
2.5
SOT-23B-3*
2.0%, 150ppm/
C Max (E Grade)
TCN4040E-2.5EZB
2.5
TO-92
2.0%, 150ppm/
C Max (E Grade)
NOTE: *SOT-23B-3 is equivalent to the JEDEC (TO-236)
NOTE: *SOT-23B-3 is equivalent to the JEDEC (TO-236)
PIN CONFIGURATION
2
3
1
NC
NC
+
+
TCN4040ENB
TCN4040EZB
1
2
3
1
2
3
4
8
7
6
5
TCN4040EOA
NC
NC
NC
NC
NC
NC
+
SOT-23B-3*
(TOP VIEW)
TO-92-3
8-Pin SOIC
TCN4040
2
PRELIMINARY INFORMATION
TCN4040-01 6/16/97
PRECISION MICROPOWER
SHUNT VOLTAGE REFERENCE
ELECTRICAL CHARACTERISTICS:
Boldface type specifications apply for T
A
= T
J
= T
MIN
to T
MAX
. All other specifica-
tions; T
A
= T
J
= 25
C.
TCN4040CEOA
TCN4040DEOA
TCN4040EENB
TCN4040CENB
TCN4040DENB
TCN4040EEZB
TCN4040CEZB
TCN4040DEZB
Symbol Parameter
Test
Min
Typ
Max
Min
Typ
Max
Min
Typ
Max
Unit
Conditions
V
R
Reverse Breakdown
I
R
=100
A
--
2.500
--
--
2.500
--
-- 2.500
--
V
Voltage
Notes 4, 5
Reverse Breakdown
I
R
=100
A
--
12
--
25
--
--
50
mV
Voltage Tolerance
Notes 4, 5, 6
--
29
--
49
--
74
I
RMIN
Minimum Operating
Notes 4, 5
--
45
60
--
45
65
--
45
65
A
Current
--
65
--
70
--
70
V
R
/
T
Average Reverse
I
R
=10mA
--
20
100
--
20
150
--
20
150
ppm/
C
Breakdown Voltage
I
R
=1mA
15
15
15
Temperature
I
R
=100
A
15
15
15
Coefficient
Notes 4, 5
V
R
/
I
R
Reverse Breakdown
I
RMIN
I
R
1mA
--
0.4
0.8
--
0.4
1.0
--
0.4
1.0
mV
Voltage Change with Notes 4, 5
--
1.0
--
1.2
--
1.2
Operating Current
Change
1mA
I
R
=12mA
--
2.3
6.0
--
2.3
8.0
--
2.3
8.0
mV
--
8.0
--
10.0
--
10.0
Z
R
Reverse Dynamic
I
R
=1mA, f = 120Hz,
--
0.3
0.9
--
0.3
1.1
--
0.3
1.1
Impedance
I
AC
= 0.1 I
R
Notes 4, 5
ABSOLUTE MAXIMUM RATINGS* (Note 1)
Reverse Current. ....... ...............................................20mA
Forward Current ....... ................................................10mA
Power Dissipation (T
A
= 25
C) (Note 2)
SOT-23B-3 Package ...................................... 230mW
TO-92 Package .............................................. 440mW
SO-8 Package ................................................ 470mW
Storage Temperature ........................... 65
C to + 150
C
Lead Temperature (Soldering, 10 seconds)
EOA ................................................................ +260
C
ENB ................................................................ +300
C
EZB ................................................................. +300
C
ESD Susceptibility
Human Body Model (Note 3) ................................ 2kV
Machine Model (Note 3) .................................... .200V
*Functional operation above the absolute maximum stress rating is not
implied.
OPERATING RATINGS (NOTES 1 AND 2)
Temperature Range
(T
MIN
T
A
T
MAX
) ..................... 40
C
T
A
+85
C
Reverse Current
TCN4040-2.5 ...................................... .60
A to 15mA
NOTES: 1. Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which
the device is functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see
Electrical
Characteristics. 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.
2. The maximum power dissipation must be derated at elevated temperatures and is dictated by T
JMAX
(maximum junction temperature),
JA
(junction to ambient thermal resistance), and T
A
(ambient temperature). The maximum allowable power dissipation at any temperature is
PD
MAX
= (T
JMAX
T
A
) /
JA
or the number given in Absolute Maximum Ratings, whichever is lower. For the TCN4040, T
JMAX
= 125
C, and
the typical thermal resistance (
JA
), when board mounted, is 185
C/W for the M package, 326
C/W for the SOT-23B-3 package, and 180
C/W with 0.4" lead length and 170
C/W with 0.125" lead length for the TO-92-3 package.
3. The human body model is a 100pF capacitor discharged through a 1.5k
resistor into each pin. The machine model is a 200pF capacitor
discharged directly into each pin.
TCN4040
3
PRELIMINARY INFORMATION
TCN4040-01 6/16/97
PRECISION MICROPOWER
SHUNT VOLTAGE REFERENCE
ELECTRICAL CHARACTERISTICS (Cont.):
Boldface type specifications apply for T
A
= T
J
= T
MIN
to T
MAX
. All other
specifications; T
A
= T
J
= 25
C.
TCN4040CEOA
TCN4040DEOA
TCN4040EENB
TCN4040CENB
TCN4040DENB
TCN4040EEZB
TCN4040CEZB
TCN4040DEZB
Symbol Parameter
Test
Min Typ Max
Min
Typ
Max Min Typ Max
Unit
Conditions
e
N
Wideband Noise
I
R
=100
A,
--
35
--
--
35
--
--
35
--
Vmsec
10Hz
f
10kHz
Notes 4, 5
V
R
Reverse Breakdown
t =1000hrs
--
120
--
--
120
--
--
120
--
ppm/
C
Voltage Long Term
T = 25
C
0.1
C
Stability
I
R
=100
A
Notes 4, 5
NOTES: 4. Typicals are at T
J
= 25
C and represent most likely parametric norm.
5. Limits are 100% production tested at 25
C.
6. The boldface (over-temperature) limit for Reverse Breakdown Voltage Tolerance is defined as the room temperature Reverse Breakdown
Voltage Tolerance
[(
V
R
/
T)(65
C)(V
R
)].
V
R
/
T is the V
R
temperature coefficient, 65
C is the temperature range from 40
C to the
reference point of 25
C, and V
R
is the reverse breakdown voltage. The total over-temperature tolerance for the different grades is shown
below:
C-grade:
1.15% =
0.5%
100ppm/
C x 65
C
D-grade:
1.98% =
1.0%
150ppm/
C x 65
C
E-grade:
2.98% =
2.0%
150ppm/
C x 65
C
PIN DESCRIPTION
Pin No.
Pin No.
Pin No.
(SOT-23B-3)
TO-92
8-Pin SOIC
Symbol
Description
1
1
1
NC
No connection
2
NC
No connection
3
NC
No connection
2
2
+
Positive terminal
3
3
Negative terminal
4
Negative terminal
5
NC
No connection
6
NC
No connection
7
NC
No connection
8
+
Positive terminal
TCN4040
4
PRELIMINARY INFORMATION
TCN4040-01 6/16/97
PRECISION MICROPOWER
SHUNT VOLTAGE REFERENCE
APPLICATIONS INFORMATION
Available in a space saving SOT-23B-3 surface mount
package, the TCN4040 is a precision micro-power curva-
ture-corrected bandgap shunt voltage reference. The
TCN4040 is designed for stable operation without an exter-
nal capacitor connected between the "+" pin and the "" pin.
The TCN4040 also remains stable, however, if a bypass
capacitor is used. The minimum operating current increase
is 60mA and the maximum operating current is 15mA.
The TCN4040, in the SOT-23B-3 package has a para-
sitic Schottky diode between pin 3 () and pin 1. (Die attach
interface contact). Therefore, pin 1 of the SOT-23B-3 pack-
age must be left floating or connected to pin 3.
In a conventional shunt regulator application, an exter-
nal series resistor (R
S
) is connected between the supply
voltage and the TCN4040 (Figure 1). R
S
determines the
current that flows through the load (I
L
) and the TCN4040
(I
Q
). Even when the supply voltage is at its minimum, and
the load current is at its maximum value, R
S
should be small
enough to supply at least the minimum acceptable I
Q
to the
TCN4040 since load current and supply voltage may vary.
Conversely, when the supply voltage is at its maximum and
I
L
is at its minimum, R
S
should be large enough that the
current flowing through the TCN4040 is less than 15mA.
Figure 1. Shunt Regulator
R
S
I
L
I
Q
+
I
L
I
Q
V
R
V
S
TCN4040
R
S
is determined by the supply voltage, (V
S
), the load
and operating current, (I
L
and I
Q
), and the TCN4040's
reverse breakdown voltage, V
R
.
V
S
V
R
R
S
=
I
L
+ I
Q
TCN4041
1
PRELIMINARY INFORMATION
TCN4041-01 6/19/97
PRECISION MICROPOWER
SHUNT VOLTAGE REFERENCE
TCN4041
FEATURES
s
Small Packages ....... SOT-23B-3, TO-92, and SO-8
s
Output Capacitor Not Required
s
Handles Capacitive Loads
s
Adjutable Voltage and Fixed Reverse Breakdown
Voltage of 1.2V
s
Low Output Noise
s
Wide Operating Current Range (60
A to 15mA)
s
40
C to + 85
C Operating Temperature Range
APPLICATIONS
s
Portable, Battery-Powered Equipment
s
Data Acquisition Systems
s
Instrumentation
s
Process Control
s
Energy Management
s
Product Testing
s
Automotive
s
Precision Audio Components
PRECISION MICROPOWER SHUNT VOLTAGE REFERENCE
TelCom Semiconductor reserves the right to make changes in the circuitry and specifications to its devices.
GENERAL DESCRIPTION
For applications in tight quarters, the TCN4041 preci-
sion voltage reference is available in a space-saving
3mm x 1.3mm SOT-23B-3 surface mount package. The
TCN4041 eliminates the need for an external stabilizing
capacitor while maintaining stability with any capacitive
load. The minimum operating current is for both the TCN4041-
1.2V and the TCN4041-ADJ. Both versions have a maxi-
mum operating current of 12mA.
To ensure that the prime parts have an accuracy of
better than
0.5% (C grade) at 25
C, the TCN4041 uses
fuse and zener-zap reverse breakdown voltage trim during
wafer sort. Low dynamic impedance and bandgap reference
temperature drift curvature correction maintain stable re-
verse breakdown voltage accuracy over a wide range of
operating temperatures ( 40
C to + 85
C) and currents
from (60
A to 12mA).
The TCN4041 is available in small SOT-23, TO-92, and
SO-8 packages.
ORDERING INFORMATION
Output
Voltage Tolerance
Part No.
Voltage (V)
Package
Temp. Coefficient Grade
TCN4041C-1.2ENB
1.2
SOT-23B-3*
0.5%, 100ppm/
C Max (C Grade)
TCN4041C-ADJENB
ADJ
SOT-23B-3*
0.5%, 100ppm/
C Max (C Grade)
TCN4041C-1.2EOA
1.2
8-Pin SOIC
0.5%, 100ppm/
C Max (C Grade)
TCN4041C-ADJEOA
ADJ
8-Pin SOIC
0.5%, 100ppm/
C Max (C Grade)
TCN4041C-1.2EZB
1.2
TO-92
0.5%, 100ppm/
C Max (C Grade)
TCN4041C-ADJEZB
ADJ
TO-92
0.5%, 100ppm/
C Max (C Grade)
TCN4041D-2.5EOA
2.5
8-Pin SOIC
1.0%, 150ppm/
C Max (D Grade)
TCN4041D-4.1EOA
4.1
8-Pin SOIC
1.0%, 150ppm/
C Max (D Grade)
TCN4041D-1.2ENB
1.2
SOT-23B-3*
1.0%, 150ppm/
C Max (D Grade)
TCN4041D-ADJENB
ADJ
SOT-23B-3*
1.0%, 150ppm/
C Max (D Grade)
TCN4041D-1.2EZB
1.2
TO-92
1.0%, 150ppm/
C Max (D Grade
TCN4041D-ADJEZB
ADJ
TO-92
1.0%, 150ppm/
C Max (D Grade)
TCN4041E-1.2ENB
1.2
SOT-23B-3*
2.0%, 150ppm/
C Max (E Grade)
TCN4041E-1.2EZB
1.2
TO-92
2.0%, 150ppm/
C Max (E Grade)
NOTE: *SOT-23B-3 is equivalent to the JEDEC (TO-236)
TCN4041
2
PRELIMINARY INFORMATION
TCN4041-01 6/19/97
PRECISION MICROPOWER
SHUNT VOLTAGE REFERENCE
ABSOLUTE MAXIMUM RATINGS* (Note 1)
Reverse Current. ....... ...............................................20mA
Forward Current ....... ................................................10mA
Power Dissipation (T
A
= 25
C) (Note 2)
SOT-23B-3 Package ...................................... 230mW
TO-92 Package .............................................. 440mW
SO-8 Package ................................................ 470mW
Storage Temperature ........................... 65
C to + 150
C
Lead Temperature (Soldering, 10 seconds)
EOA ................................................................ +260
C
ENB ................................................................ +300
C
EZB ................................................................. +300
C
ESD Susceptibility
Human Body Model (Note 3) ................................ 2kV
Machine Model (Note 3) .................................... .200V
*Functional operation above the absolute maximum stress rating is not
implied.
OPERATING RATINGS (NOTES 1 AND 2)
Temperature Range
(T
MIN
T
A
T
MAX
) ..................... 40
C
T
A
+85
C
Reverse Current
TCN4041-1.2 ....................................... 60
A to 12mA
TCN40401-ADJ .................................... 68
A to12mA
Output Voltage Range
TCN4041-ADJ ....................................... 1.24V to 10V
NOTES: 1. Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which
the device is functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see
Electrical
Characteristics. 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.
2. The maximum power dissipation must be derated at elevated temperatures and is dictated by T
JMAX
(maximum junction temperature),
JA
(junction to ambient thermal resistance), and T
A
(ambient temperature). The maximum allowable power dissipation at any temperature is
PD
MAX
= (T
JMAX
T
A
) /
JA
or the number given in Absolute Maximum Ratings, whichever is lower. For the TCN4041, T
JMAX
= 125
C, and
the typical thermal resistance (
JA
), when board mounted, is 185
C/W for the M package, 326
C/W for the SOT-23B-3 package, and 180
C/W with 0.4" lead length and 170
C/W with 0.125" lead length for the TO-92-3 package.
3. The human body model is a 100pF capacitor discharged through a 1.5k
resistor into each pin. The machine model is a 200pF capacitor
discharged directly into each pin.
ELECTRICAL CHARACTERISTICS:
Boldface type specifications apply for T
A
= T
J
= T
MIN
to T
MAX
. All other specifica-
tions; T
A
= T
J
= 25
C. All other specifications; T
A
= T
J
= 25
C. The grades C, D,
and E designate initial Reverse Breakdown Voltage tolerances of
0.5%,
1.0%,
and
2.0%, respectively.
TCN4041CEOA
TCN4041DEOA
TCN4041EENB
TCN4041CENB
TCN4041DENB
TCN4041EEZB
TCN4041CEZB
TCN4041DEZB
Symbol Parameter
Test
Min
Typ
Max
Min
Typ
Max
Min
Typ
Max
Unit
Conditions
V
R
Reverse Breakdown
I
R
=100
A
--
1.225
--
--
2.500
--
-- 2.500
--
V
Voltage
Notes 4, 5
Reverse Breakdown
I
R
=100
A
--
6
--
12
--
--
25
mV
Voltage Tolerance
Notes 4, 5, 6
--
14
--
24
--
36
I
RMIN
Minimum Operating
Notes 4, 5
--
45
60
--
45
65
--
45
65
A
Current
--
65
--
70
--
70
V
R
/
T
Average Reverse
I
R
=10mA
--
20
100
--
20
160
--
20
150
ppm/
C
Breakdown Voltage
I
R
=1mA
15
15
15
Temperature
I
R
=100
A
15
15
15
Coefficient
Notes 4, 5
V
R
/
I
R
Reverse Breakdown
I
RMIN
I
R
1mA
--
0.7
1.5
--
0.4
2.0
--
0.4
2.0
mV
Voltage Change with Notes 4, 5
--
2.0
--
2.5
--
2.5
Operating Current
Change
1mA
I
R
=12mA
--
2.5
6.0
--
2.3
8.0
--
2.3
8.0
mV
--
8.0
--
10.0
--
10.0
Z
R
Reverse Dynamic
I
R
=1mA, f = 120Hz,
--
0.5
1.5
--
0.3
2.0
--
0.3
2.0
Impedance
I
AC
= 0.1 I
R
Notes 4, 5
TCN4041
3
PRELIMINARY INFORMATION
TCN4041-01 6/19/97
PRECISION MICROPOWER
SHUNT VOLTAGE REFERENCE
ELECTRICAL CHARACTERISTICS (Cont.):
Boldface type specifications apply for T
A
= T
J
= T
MIN
to T
MAX
. All other
specifications; T
A
= T
J
= 25
C. The grades C, D, and E designate initial
Reverse Breakdown Voltage tolerances of
0.5%,
1.0%, and
2.0%,
respectively.
TCN4041CEOA
TCN4041DEOA
TCN4041EENB
TCN4041CENB
TCN4041DENB
TCN4041EEZB
TCN4041CEZB
TCN4041DEZB
Symbol Parameter
Test
Min Typ Max
Min
Typ
Max Min Typ Max
Unit
Conditions
e
N
Wideband Noise
I
R
=100
A,
--
20
--
--
20
--
--
20
--
Vmsec
10Hz
f
10kHz
Notes 4, 5
V
R
Reverse Breakdown
t =1000hrs
--
120
--
--
120
--
--
120
--
ppm/
C
Voltage Long Term
T = 25
C
0.1
C
Stability
I
R
=100
A
Notes 4, 5
NOTES: 4. Typicals are at T
J
= 25
C and represent most likely parametric norm.
5. Limits are 100% production tested at 25
C.
6. The boldface (over-temperature) limit for Reverse Breakdown Voltage Tolerance is defined as the room temperature Reverse Breakdown
Voltage Tolerance
[(
V
R
/
T)(65
C)(V
R
)].
V
R
/
T is the V
R
temperature coefficient, 65
C is the temperature range from 40
C to the
reference point of 25
C, and V
R
is the reverse breakdown voltage. The total over-temperature tolerance for the different grades is shown
below:
C-grade:
1.15% =
0.5%
100ppm/
C x 65
C
D-grade:
1.98% =
1.0%
150ppm/
C x 65
C
E-grade:
2.98% =
2.0%
150ppm/
C x 65
C
7. When VOUT
1.6V, the TCN4041-ADJ in the SOT-23B package must operate at reduced IR. This is caused by the series resistance of the
die attach between the die (-) output and the package (-) output pin. See the Output Saturation (SOT23-B only) curve in the
Typical
Characteristics section.
8. Reference voltage and temperature coefficient will change with output voltage. See
Typical Characteristics curves.
NOTE: *SOT-23B-3 is equivalent to the JEDEC (TO-236)
PIN CONFIGURATION
2
3
1
NC
NC
+
+
TCN4041ENB-1.2V
2
3
1
NC
+
TCN4041ENB-ADJ
TCN4041EZB-1.2V
1
2
3
1
2
3
4
8
7
6
5
TCN4041EOA-1.2V
TCN4041EOA-ADJ
NC
NC
NC
NC
NC
NC
+
SOT-23B-3*
(TOP VIEW)
TO-92-3
8-Pin SOIC
1
2
3
4
8
7
6
5
NC
NC
NC
NC
NC
NC
+
TCN4041-ADJ
1
2
3
TCN4041
4
PRELIMINARY INFORMATION
TCN4041-01 6/19/97
PRECISION MICROPOWER
SHUNT VOLTAGE REFERENCE
Output voltage on the TCN4041-ADJ can be adjusted to
any value between 1.24V and 10V. It is a function of the
internal reference voltage (V
REF
) and the ratio of the external
feedback resistors (see Figure 2). The output can be found
with the equation (where V
OUT
is the desired output voltage):
V
OUT
= V
REF
(R2/R1 + 1)
Equation 1.
The value of the internal V
REF
is a function of V
O
. The
"corrected" V
REF
can be determined by (where V
O
is the
desired output voltage):
V
REF'
= V
OUT
V
REF
/
V
OUT
) +V
Y
Equation 2.
V
REF
/
V
OUT
is typically -1.3mV/V, and V
Y
= 1.240V.
Replace the value of V
REF'
in Equation 1 with the value
determined using Equation 2.
The actual output voltage can deviate from that pre-
dicted by the typical
V
REF
/
V
O
in Equation 2. The worst
case
V
REF
/
V
OUT
for C-grade parts is 2.5mV/V and
V
Y
= 1.246V; for D-grade, the worst case is 3.0mV/V and
V
Y
= 1.248V.
The difference in output voltage resulting from typical
worst case values are shown in the following example: Let
V
O
= +9V. Using the typical value of
V
REF
/
V
OUT
, V
REF
is
1.228; choosing a value of R1 = 10k
, R2 = 63.272kW. The
output voltage, when using worst case
V
REF
/
V
OUT
for
C-grade and D-grade parts, is 8.965V and 8.946V, respec-
tively. This could result in errors as large as 0.39% for
C-grade, and 0.59% for D-grade parts. However, resistor
values resulting from the typical value of
V
REF
/
V
OUT
will
work most of the time, requiring no additional adjustments.
APPLICATIONS INFORMATION
Available in space-saving SOT-23B-3 surface
mount packages, the TCN4041 is a precision micro-power
curvature-corrected bandgap shunt voltage reference. It is
designed for stable operation without an external capacitor
connected between the "+" pin and the "-" pin. The TCN4041
also remains stable, however, if a bypass capacitor is used.
The device is available in either a fixed 1.2V or an adjustable
reverse breakdown voltage. The minimum operating cur-
rent is 60mA, and the maximum operating current is 12mA
for both options.
TCN4041s in the SOT-23 package have pin 1
connected as the (-) output. (Die attach interface contact).
Therefore, pin 1 of the TCN4041-1.2 must be left floating or
connected to pin 3, and pin 1 on the TCN4041-ADJ is the
(-) output.
In a conventional shunt regulator application, an
external series resistor (R
S
) is connected between the
supply voltage and the TCN4041 (Figure 1). R
S
determines
the current that flows through the load (I
L
) and the TCN4041
(I
Q
). Even when the supply voltage is at its minimum, and
the load current is at its maximum value, R
S
should be small
enough to supply at least the minimum acceptable I
Q
to the
TCN4041 since load current and supply voltage may vary.
Conversely, when the supply voltage is at its maximum and
I
L
is at its minimum, R
S
should be large enough that the
current flowing through the TCN4041 is less than 12mA.
R
S
is determined by the supply voltage, (V
S
), the
load and operating current, (I
L
and I
Q
), and the TCN4041's
reverse breakdown voltage, V
R
.
V
S
- V
R
R
S
=
I
L
+ I
Q
PIN DESCRIPTION
Pin No.
Pin No.
Pin No.
(SOT-23B-3)
TO-92
8-Pin SOIC
Symbol
Description
1
1
1
NC
No connection
2
NC
No connection
3
NC
No connection
2
2
+
Positive terminal
3
3
Negative terminal
4
Negative terminal
5
NC
No connection
6
NC
No connection
7
NC
No connection
8
+
Positive terminal
TCN4041
5
PRELIMINARY INFORMATION
TCN4041-01 6/19/97
PRECISION MICROPOWER
SHUNT VOLTAGE REFERENCE
Figure 1. Shunt Regulator
R
S
I
L
I
Q
+
I
L
I
Q
V
R
V
S
TCN4041
Figure 2. Adjustable Shunt
R
S
R
1
R
2
V
OUT
V
S
TCN4041-ADJ
PDF 
ZIP