LM368

Na t ion S e m i c o n d u c t o r

LM 368-5.0 and LM 368-10 Precision V o ltag e R efe ren ce s

General Description Features
The LM368 is a precision, monolithic, temperature-compen­ ■ 300 jllA operating current
sated voltage reference. The LM368 makes use of thin-film ■ Low output impedance
technology enhanced by the discrete laser trimming of re­ ■ Excellent line regulation (.0001 % /V typical)
sistors to achieve excellent Temperature coefficient ■ Single-supply operation
(Tempco) of Vout (as low as 5ppm/°C), along with tight D Externally trimmable
initial tolerance, (as low as 0.02%). The trim scheme is such
■ Low temperature coefficient
that individual resistors are cut open rather than being
■ Operates in series or shunt mode
trimmed (partially cut), to avoid resistor drift caused by elec­
tromigration in the trimmed area. The LM368 also provides ■ 10.0V or 5.0V
excellent stability vs. changes in input voltage and output ■ Excellent initial accuracy (0.02% typical)
current (both sourcing and sinking). This device is available
in output voltage options of 5.0V and 10.0V and will operate
in both series or shunt mode. Also see the LM368-2.5 data
sheet for a 2.5V output. The devices are short circuit proof
when sourcing current. A trim pin is made available for fine
trimming of Vqut or for obtaining intermediate values with­
out greatly affecting the Tempco of the device.

Connection Diagram
M etal C an Package
NC

•case connected to V~

O rd e r N um ber LM 368Y H -10,

LM 368Y H -5.0, LM 368H -10, LM 368H -5.0
S ee NS P ackage N um ber H08C
Typical Applications
S eries R e g u la to r S hunt R e g u la to r

13V-30V
Ji 1 mA-10 mA

LM368-10.0 — 10.000V

Jf
LM368-5.0

JT "

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 LM368
Absolute Maximum Ratings (Notes)
Input Voltage (Series Mode) 35V Soldering Information
Reverse Current (Shunt Mode) 50 mA TO-5 (H) Package, 10 sec. +300°C
Power Dissipation 600 mW See AN-450 “ Surface Mounting Methods and Their Effect
on Product Reliability” (Appendix D) for other methods of
Storage Temperature Range - 60°C to + 1 50°C
soldering surface mount devices.
Operating Temperature Range
LM368 0°C to + 70°C
Electrical Characteristics (Noted
LM368
Tested Design Units
Parameter Conditions Limit Limit (Max. unless
Typical
(Note 2) (Note 3) noted)
Vout Error ±0.02 ±0.1 %
Line Regulation (Vout +3V) £ v,N <; 30V ±0.0001 ±0.0005 %/V
Load Regulation 0 mA < Isource ^ 1 0 mA ±0.0003 ±0.001 %/mA
(Note 4) —10 mA ^ IsiNK ^ 0 mA ±0.003 ±0.008 %/mA
Thermal Regulation T = 20 mS (Note 5) ±0.005 ±0.01 %/100 mW
Quiescent Current 250 350 jiA

Change of Quiescent Current vs. Vin (Vout + 3V) ^ Vin £ 30V 3 5 jllA/V

Temperature Coefficient
of Vout (see graph): LM368Y 0°C ^ TA ^ 70°C ±11 ±20 ppm/°C
(Note 6) LM368 o°c <; t a <; 70°c ±15 ±30 ppm/°C
Short Circuit Current Vout = o 30 70 100 mA
Noise: 10.0V: 0.1 - 10Hz 30 uVp-p
100Hz-10 kHz 1100 nV/VRz
6.2V: 0.1 -10Hz 20 uVp-p
100Hz-10 kHz 700 nV/i/Hz
5.0V: 0.1 - 10Hz 16 uVp-p
100Hz-10 kHz 575 nV/i/Hz
Vout Adjust Range: 10.000V 0V ^ VP|N5 ^ Vqut 4.5-17.0 6.0-15.5 V min.
5.000V 4.4-7.0 4.5-6.0 V min.

Note 1: Unless otherwise noted, these specifications apply: Ta = 25°C, V in = 15V, Iload = 0,0 ^ Cl ^ 200 pF, Circuit is operating in Series Mode. Or, circuit is
operating in Shunt Mode, Vin = + 15V or V|N = Vout . TA = +25°C, Iload = - 1 .0 mA, 0 £ Cl ^ 200 pF.
Note 2: Tested Limits are guaranteed and 100% tested in production.
Note 3: Design Limits are guaranteed (but not 100% production tested) over the indicated temperature and supply voltage ranges. These limits are not used to
calculate outgoing quality levels.
Note 4: The LM368 has a Class B output, and will exhibit transients at the crossover point. This point occurs when the device is asked to sink approximately
120 jxA. In some applications it may be advantageous to preload the output to either V in or Ground, to avoid this crossover point.
Note 5: Thermal Regulation is defined as the change in the output Voltage at a time T after a step change in power dissipation of 100 mW.
Note 6: Temperature Coefficient of Vout is defined as the worst case delta-VouT measured at Specified Temperatures divided by the total span of the Specified
Temperature Range (See graphs). There is no guarantee that the Specified Temperatures are exactly at the minimum or maximum deviation.
Note 7: In metal can (H), 0 j_ c is 75°C/W and 0 j_ A is 150°C/W.
Note 8: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications do not apply when operating
the device beyond its Rated Operating Conditions (see Note 1 and Conditions).

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 LM368

4-90
 LM368
Typical A pplications
W id e R ange Trim m a b le R egulator N a rro w R ange T rim m able R eg u lato r (± 1% min.)

6
f — V 0UT -VOUT
LM368 l LM36B
_5 > R1
"" > 20k

f TL/H /5522-7

Im proved N oise P erfo rm an ce

v+

A d ju s ta b le Z e n e r
v+

TL/H/5522-10

± 1 0 V , ± 5 V R e fe re n c e s
v+

TL/H /5522-9

± R e fe re n c e
v+
I?
•+voui

3 = 1/4 LF444A or

>
V2 LF412A

- -VoUT
TL/H/5522-12
1mA . R= Thin Film Resistor Network,
±0.05% Matching and 5ppm Tracking
(Beckman 694-3-R-10K-A),
TL/H /5522-11 (Caddock T-914-10K-100-05)
or similar.

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LM368
Typical Applications (Continued)

M ultiple O u tp u t V o lta g e s
v+ V+

TL/H /5522-14

TL/H/5522-13

V+

Thin Film Resistor Network

0.05% Matching and 5ppm Tracking
(Beckman 694-3-R-10K-A),
(Caddock T-914-10K-100-05)
or similar.

R e fe re n c e w ith B o o s te r 100 m A B o o s te d R e fe re n c e
v+ v+

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 LM368
Typical Applications (Continued)

B u ffe re d H igh-C urren t R e fe re n c e w ith Filter

v+

TL/H/5522-18

Sim plified Schematic Diagram

TL/H /5522-6

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