VRE310BS [CIRRUS]

P r o d u c t I

I

n n o v

v

a t i o n F

F r o m

rom

nno a

VRE310

VRE310

DESCRIPTION

Precision Voltage Reference

FEaTuRES

♦

♦

♦

♦

+10 V Output, ±1.0 mV (.01%)

Temperature Drift: 0.6 ppm/ºC

Low Noise: 6 μV

P-P

(0.1-10Hz)

Industry Standard Pinout: 8-pin DIP or Surface

Mount Package

♦ Excellent Line Regulation: 6 ppm/V Typical

♦ Output Trim Capability

The VRE310 is a low cost, high precision +10 V refer-

ence. Available in an industry standard 8-pin DIP or

SMT, the device is ideal for upgrading systems that

use lower performance references.

The device provides ultrastable +10 V output with ±1.0

mV (.01%) initial accuracy and a temperature coeffi-

cient of 0.6 ppm/ºC. This improvement in accuracy is

made possible by a unique, patented multipoint laser

compensation technique. Significant improvements

have been made in other performance parameters

as well, including initial accuracy, warm-up drift, line

regulation, and long-term stability, making the VRE310

series the most accurate reference available in a stan-

dard 8-pin DIP or SMT package.

For enhanced performance, the VRE310 has an exter-

nal trim option for users who want less than 0.01% ini-

tial error. For ultra low noise applications, an external

capacitor can be attached between the noise reduction

pin and the ground pin. A reference ground pin is pro-

vided to eliminate socket contact resistance errors.

aPPlICaTIONS

The VRE310 is recommended for use as a refer-

ence for 14, 16, or 18-bit D/A converters which re-

quire an external precision reference. The device

is also ideal for calibrating scale factor on high

resolution A/D converters. The VRE310 offers su-

perior performance over monolithic references.

Figure 1. BlOCK DIaGRaM

SElECTION GuIDE

Model

VRE310AS

VRE310AD

VRE310BS

VRE310BD

VRE310CS

VRE310CD

VRE310JS

VRE310JD

Initial Error Temp. Coeff.

(mV)

(ppm/ºC)

1.0

1.0

1.6

1.6

2.0

2.0

1.0

1.0

0.6

0.6

1.0

1.0

2.0

2.0

0.6

0.6

Temp. Range

(ºC)

0ºC to +70ºC

0ºC to +70ºC

0ºC to +70ºC

0ºC to +70ºC

0ºC to +70ºC

0ºC to +70ºC

-40ºC to +85ºC

-40ºC to +85ºC

Package

Options

SMT8 (GD)

DIP8 (KD)

SMT8 (GD)

DIP8 (KD)

SMT8 (GD)

DIP8 (KD)

SMT8 (GD)

DIP8 (KD)

8-pin Surface Mount

8-pin DIP

Package Style GD

Package Style KD

VRE310DS

http://www.cirrus.com

Copyright © Cirrus Logic, Inc. 2009

(All Rights Reserved)

MaR 2009

1

APEX − VRE310DSREVE

VRE310

P r o d u c t I n n o v a t i o nF r o m

1. ChaRaCTERISTICS aND SPECIFICaTIONS

ElECTRICal SPECIFICaTIONS

V

PS

=±15V, T = +25ºC, R

L

= 10KΩ Unless Otherwise Noted.

Model

Parameter

Power Supply

Operating Temperature (A,B,C)

Operating Temperature (J)

Storage Temperature

Short Circuit Protection

OuTPuT VOlTaGE

VRE310

Temp. Sensor Voltage (Note 1)

OuTPuT VOlTaGE ERRORS

Initial Error

Warmup Drift

T

MIN

- T

MAX

Long-Term Stability

Noise (0.1 - 10Hz)

OuTPuT CuRRENT

Range

REGulaTION

Line

Load

OuTPuT aDJuSTMENT

Range

POWER SuPPlY CuRRENT

(Note 5)

VRE310 +PS

5

7

*

*

*

*

mA

20

*

*

mV

6

3

10

*

*

*

*

*

*

ppm/V

ppm/mA

±10

*

mA

(Note 4)

(Note3)

6

6

(Note 2)

1

0.6

*

*

±1.0

2

1.0

*

*

±1.6

3

2.0

±2.0

mV

ppm

ppm/ºC

ppm/1000hrs.

µVpp

+10.0

630

*

*

*

*

V

mV

Min

±13.5

0

-40

-65

Continuous

aBSOluTE MaXIMuM RaTINGS

±15

±22

+70

+85

+150

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

V

ºC

ºC

ºC

a/J

Typ

Max

Min

B

Typ

Max

Min

C

Typ

Max

units

NOTES:

* Same as A/J Models.

1. The temp. reference TC is 2.1 mV/ ºC

2. The specified values are without external trim.

3. The temperature coefficient is determined by the box method using the following formula:

V

MAX

– V

MIN

T.C. =

x 10

6

V

NOMINAL

x (T

MAX

– T

MIN

)

4. The specified values are without the external noise reduction capacitor.

5. The specified values are unloaded.

2

VRE310DS

P r o d u c t I n n o v a t i o nF r o m

VRE310

2. TYPICal PERFORMaNCE CuRVES

V

OUT

vs. TEMPERATURE

V

OUT

vs. TEMPERATURE

Temperature

o

C

VRE310A

V

OUT

vs. TEMPERATURE

Temperature

o

C

VRE310B

V

OUT

vs. TEMPERATURE

Temperature

o

C

VRE310C

QUIESCENT CURRENT VS. TEMP

Temperature

o

C

VRE310J

PSRR VS. FREQUENCY

JUNCTION TEMP. RISE VS. OUTPUT CURRENT

Temperature

o

C

Output Current (mA)

Frequency (Hz)

VRE310DS

3

VRE310

3. ThEORY OF OPERaTION

P r o d u c t I n n o v a t i o nF r o m

The following discussion refers to the block diagram in Figure 1. In operation, approximately 6.3 V is applied to

the noninverting input of the op amp. The voltage is amplified by the op amp to produce a 10 V output. The gain is

determined by the networks R1 and R2: G=1 + R2/R1. The 6.3 V zener diode is used because it is the most stable

diode over time and temperature.

The zener operating current is derived from the regulated output voltage through R3. This feedback arrangement

provides a closely regulated zener current. This current determines the slope of the references’ voltage vs. tempera-

ture function. By trimming the zener current a lower drift over temperature can be achieved. But since the voltage

vs. temperature function is nonlinear this compensation technique is not well suited for wide temperature ranges.

A nonlinear compensation network of thermistors and resistors is used in the VRE series voltage references. This

proprietary network eliminates most of the nonlinearity in the voltage vs. temperature function. By then adjusting the

slope, a very stable voltage is produced over wide temperature ranges.

This network is less than 2% of the overall network resistance so it has a negligible effect on long term stability.

By using highly stable resistors in our network, we produce a voltage reference that also has very good long term

stability.

The proper connection of the VRE310 series voltage references with the optional trim resistor is shown below. The

VRE310 reference has the ground terminal brought out on two pins (pin 4 and pin 7) which are connected together

internally. This allows the user to achieve greater accuracy when using a socket. Voltage references have a volt-

age drop across their power supply ground pin due to quiescent current flowing through the contact resistance. If

the contact resistance was constant with time and temperature, this voltage drop could be trimmed out. When the

reference is plugged into a socket, this source of error can be as high as 20 ppm. By connecting pin 4 to the power

supply ground and pin 7 to a high impedance ground point in the measurement circuit, the error due to the contact

resistance can be eliminated. If the unit is soldered into place, the contact resistance is sufficiently small that it does

not effect performance. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the

lines.

EXTERNal CONNECTIONS

+ V

IN

2

V

TEMP OUT

3

6

OPTIONAL

NOISE REDUCTION

CAPACITOR

C

N

1µF

8

+ V

OUT

10k

Ω

OPTIONAL

FINE TRIM

ADJUSTMENT

VRE310

5

7

4

REF. GND

PIN CONFIGuRaTION

N/C

+V

IN

TEMP

GND

1

2

3

4

VRE310

TOP

VIEW

8

7

6

5

NOISE

REDUCTION

REF. GND

V

OUT

TRIM



VRE310DS

P r o d u c t I n n o v a t i o nF r o m

VRE310

CONTaCTING CIRRuS lOGIC SuPPORT

For all Apex Precision Power product questions and inquiries, call toll free 800-546-2739 in North America.

For inquiries via email, please contact tucson.support@cirrus.com.

International customers can also request support by contacting their local Cirrus Logic Sales Representative.

To find the one nearest to you, go to www.cirrus.com

IMPORTANT NOTICE

Cirrus Logic, Inc. and its subsidiaries ("Cirrus") believe that the information contained in this document is accurate and reliable. However, the information is subject

to change without notice and is provided "AS IS" without warranty of any kind (express or implied). Customers are advised to obtain the latest version of relevant

information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale

supplied at the time of order acknowledgment, including those pertaining to warranty, indemnification, and limitation of liability. No responsibility is assumed by Cirrus

for the use of this information, including use of this information as the basis for manufacture or sale of any items, or for infringement of patents or other rights of third

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copyrights, trademarks, trade secrets or other intellectual property rights. Cirrus owns the copyrights associated with the information contained herein and gives con-

sent for copies to be made of the information only for use within your organization with respect to Cirrus integrated circuits or other products of Cirrus. This consent

does not extend to other copying such as copying for general distribution, advertising or promotional purposes, or for creating any work for resale.

CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH, PERSONAL INJURY, OR SEVERE PROP-

ERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL APPLICATIONS”). CIRRUS PRODUCTS ARE NOT DESIGNED, AUTHORIZED OR WARRANTED TO BE

SUITABLE FOR USE IN PRODUCTS SURGICALLY IMPLANTED INTO THE BODY, AUTOMOTIVE SAFETY OR SECURITY DEVICES, LIFE SUPPORT PROD-

UCTS OR OTHER CRITICAL APPLICATIONS. INCLUSION OF CIRRUS PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO BE FULLY AT THE CUS-

TOMER’S RISK AND CIRRUS DISCLAIMS AND MAKES NO WARRANTY, EXPRESS, STATUTORY OR IMPLIED, INCLUDING THE IMPLIED WARRANTIES OF

MERCHANTABILITY AND FITNESS FOR PARTICULAR PURPOSE, WITH REGARD TO ANY CIRRUS PRODUCT THAT IS USED IN SUCH A MANNER. IF THE

CUSTOMER OR CUSTOMER’S CUSTOMER USES OR PERMITS THE USE OF CIRRUS PRODUCTS IN CRITICAL APPLICATIONS, CUSTOMER AGREES,

BY SUCH USE, TO FULLY INDEMNIFY CIRRUS, ITS OFFICERS, DIRECTORS, EMPLOYEES, DISTRIBUTORS AND OTHER AGENTS FROM ANY AND ALL

LIABILITY, INCLUDING ATTORNEYS’ FEES AND COSTS, THAT MAY RESULT FROM OR ARISE IN CONNECTION WITH THESE USES.

Cirrus Logic, Cirrus, and the Cirrus Logic logo designs, Apex Precision Power, Apex and the Apex Precision Power logo designs are trademarks of Cirrus Logic, Inc.

All other brand and product names in this document may be trademarks or service marks of their respective owners.

VRE310DS