REF60xx High-Precision Voltage Reference With Integrated ADC Drive Buffer

1 Features

• Excellent temperature drift performance

– 5ppm/°C (maximum) from –40°C to +125°C

• Extremely low noise

– Total noise: 5µVRMS with 47µF capacitor

– 1/f noise (0.1Hz to 10Hz): 3µVPP/V

• Integrated ADC drive buffer

– Low output impedance: < 50mΩ (0kHz to

200kHz)

– First sample precise to 18 bits with ADS8881

– Enables burst-mode DAQ systems

• Low supply current: 820μA

• Low shutdown current: 1µA

• High initial accuracy: ±0.05%

• Very-low noise and distortion

– SNR: 100.5dB, THD: –125dB (ADS8881)

– SNR: 106dB, THD: –120dB (ADS127L01)

• Output current drive: ±4mA

• Programmable short-circuit current

• Verified to drive REF pin of ADS88xx family of

SAR ADCs and ADS127xx family of wideband ΔΣ

ADCs

2 Applications

• ATE testers and oscilloscopes

• Test and measurement equipment

• Analog input modules for PLCs

• Medical equipment

• Precision data acquisition systems

3 Description

The REF6000 family of voltage references have an

integrated low output impedance buffer that enable

the user to directly drive the REF pin of precision

data converters, while preserving linearity, distortion,

and noise performance. Most precision SAR and

Delta-Sigma ADCs, switch binary-weighted capacitors

onto the REF pin during the conversion process.

To support this dynamic load the output of the

voltage reference must be buffered with a low-output

impedance (high-bandwidth) buffer. The REF6000

family devices are an excellent choice, but not limited,

to drive the REF pin of the ADS88xx family of SAR

ADCs, and ADS127xx family of delta-sigma ADCs, as

well as other digital-to-analog converters (DACs).

The REF6000 family of voltage references are able to

maintain an output voltage within 1LSB (18-bit) with

minimal droop, even during the first conversion while

driving the REF pin of the ADS8881. This feature is

useful in burst-mode, event-triggered, equivalent-time

sampling, and variable-sampling-rate data-acquisition

systems. The REF60xx variants of REF6000 family

specify a maximum temperature drift of just 5ppm/°C

and initial accuracy of 0.05% for both the voltage

reference and the low output impedance buffer

combined. For various temperature drift options in

REF6000 family, see the Device Comparison Table.

Package Information

PART NUMBER

PACKAGE(1)

PACKAGE SIZE(2)

REF60xx

DGK (VSSOP, 8)

3.00mm × 4.90mm

(1)

For more information, see Section 12.

(2)

The package size (length × width) is a nominal value and

includes pins, where applicable.

Bandgap

Voltage

Reference

CFILT

CL

RESR

RFILT

Buffer

+

VIN

OUT_S

OUT_F

FILT

VIN

GND_S

GND_F

Power Supply

SS

REF60xx

RLIM

EN

GND

REF

+

VIN

R

R

R

Power Supply

RF

RF

R

CF

THS4521

AINP

AINN

ADS8881

Copyright © 2016, Texas Instruments Incorporated

Typical Application

±4

±3

±2

±1

0

1

2

3

4

0

200

400

600

800

1000

Time (µs)

C042

Regular Voltage Reference Droop

REF60xx Droop

Reference Droop Comparison (1LSB = 19.07µV,

with ADS8881 at 1MSPS)

REF60

SBOS708C – MAY 2016 – REVISED APRIL 2026

An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. PRODUCTION DATA.