Home Power management AC/DC & DC/DC converters (integrated FET)
Home
Power management
AC/DC & DC/DC converters (integrated FET)

LM7705

ACTIVE

Low Noise Negative Bias Generator

Order now
Data sheet

A newer version of this product is available

open-in-new Compare alternates
Same functionality with different pin-out to the compared device
LM27761 ACTIVE Low-Noise Regulated Inverter with Integrated LDO Smaller solution size and higher output current up to 200 mA

LM7705

ACTIVE
Data sheet Order now

Product details

Rating Catalog Operating temperature range (°C) -40 to 125 Type Charge pump, Converter Iout (max) (A) 0.026 Vin (min) (V) 3 Vin (max) (V) 5.25 Switching frequency (min) (kHz) 92 Switching frequency (max) (kHz) 92 Features Enable, Regulated, Synchronous Rectification Vout (min) (V) -0.232 Vout (max) (V) -0.232 Iq (typ) (µA) 78
Rating Catalog Operating temperature range (°C) -40 to 125 Type Charge pump, Converter Iout (max) (A) 0.026 Vin (min) (V) 3 Vin (max) (V) 5.25 Switching frequency (min) (kHz) 92 Switching frequency (max) (kHz) 92 Features Enable, Regulated, Synchronous Rectification Vout (min) (V) -0.232 Vout (max) (V) -0.232 Iq (typ) (µA) 78
VSSOP (DGK) 8 14.7 mm² 3 x 4.9
  • Regulated Output Voltage −0.232 V
  • Output Voltage Tolerance 5%
  • Output Voltage Ripple 4 mVPP
  • Supply Voltage 3 V to 5.25 V
  • Conversion Efficiency Up to 98%
  • Quiescent Current 78 µA
  • Shutdown Current 20 nA
  • Turnon Time 500 µs
  • Operating Temperature Range −40°C to 125°C
  • 8-Pin VSSOP Package
  • Regulated Output Voltage −0.232 V
  • Output Voltage Tolerance 5%
  • Output Voltage Ripple 4 mVPP
  • Supply Voltage 3 V to 5.25 V
  • Conversion Efficiency Up to 98%
  • Quiescent Current 78 µA
  • Shutdown Current 20 nA
  • Turnon Time 500 µs
  • Operating Temperature Range −40°C to 125°C
  • 8-Pin VSSOP Package

The LM7705 device is a switched capacitor voltage inverter with a low noise, −0.23 V fixed negative voltage regulator. This device is designed to be used with low voltage amplifiers to enable the amplifiers output to swing to zero volts. The −0.23 V is used to supply the negative supply pin of an amplifier while maintaining less then 5.5 V across the amplifier. Rail-to-Rail output amplifiers cannot output zero volts when operating from a single-supply voltage and can result in error accumulation due to amplifier output saturation voltage being amplified by following gain stages. A small negative supply voltage will prevent the amplifiers output from saturating at zero volts and will help maintain an accurate zero through a signal processing chain. Additionally, when an amplifier is used to drive an input of the ADC, the amplifier can output a zero voltage signal and the full input range of an ADC can be used. The LM7705 device has a shutdown pin to minimize standby power consumption.

The LM7705 device is a switched capacitor voltage inverter with a low noise, −0.23 V fixed negative voltage regulator. This device is designed to be used with low voltage amplifiers to enable the amplifiers output to swing to zero volts. The −0.23 V is used to supply the negative supply pin of an amplifier while maintaining less then 5.5 V across the amplifier. Rail-to-Rail output amplifiers cannot output zero volts when operating from a single-supply voltage and can result in error accumulation due to amplifier output saturation voltage being amplified by following gain stages. A small negative supply voltage will prevent the amplifiers output from saturating at zero volts and will help maintain an accurate zero through a signal processing chain. Additionally, when an amplifier is used to drive an input of the ADC, the amplifier can output a zero voltage signal and the full input range of an ADC can be used. The LM7705 device has a shutdown pin to minimize standby power consumption.
filter Find other AC/DC & DC/DC converters (integrated FET)
Download View video with transcript Video

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 7
Type Title Date
* Data sheet LM7705 Low-Noise Negative Bias Generator datasheet (Rev. D) PDF | HTML 08 May 2018
Circuit design Charge pump circuit (–0.3V) for negative amplifier supply (Rev. A) PDF | HTML 21 Aug 2024
Application note Quick Reference Guide To TI Buck Switching DC/DC Application Notes (Rev. B) PDF | HTML 23 May 2022
Technical article How to achieve microvoltage-level precision in thermopile applications PDF | HTML 09 Dec 2021
Application note Attenuator Amplifier Design to Maximize the Input Voltage of Differential ADCs 14 Jun 2018
Technical article Unique active mux capability combines buffer and switch into one solution PDF | HTML 10 Oct 2017
EVM User's guide AN-1883 LM7705 Evaluation Board (Rev. B) 03 May 2013

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Evaluation board

ADS8168EVM-PDK — ADS8168 8-channel 16-bit 1MSPS SAR ADC evaluation module performance demonstration kit (PDK)

The ADS8168 evaluation module (EVM) performance demonstration kit (PDK) is a platform for evaluating the performance of the ADS8168 successive-approximation register (SAR) analog-to-digital converter (ADC). The ADS8168EVM-PDK includes the ADS8168EVM board, the precision host interface (PHI) (...)

User guide: PDF
Not available on TI.com
Evaluation board

LM7705MMEVAL — Evaluation Board for the LM7705

This evaluation board is designed to demonstrate the functionality of Texas Instruments LM7705 Low Noise Negative Bias Generator. The board has a dual Operational Amplifier that can be connected to ground or biased with the on board LM7705. In the last case a True zero amplifier is demonstrated.

User guide: PDF
Not available on TI.com
Reference designs

TIDA-01056 — 20-bit 1MSPS DAQ Reference Design Optimizing Power Supply Efficiency While Minimizing EMI

This reference design for high performance data acquisition (DAQ) systems optimizes power stage in order to reduce power consumption and minimize the effect of EMI from switching regulator by using LMS3635-Q1 buck converter.  This reference designs yields 7.2% efficiency improvement at most (...)
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-01054 — Multi-Rail Power Reference Design for Eliminating EMI Effects in High Performance DAQ Systems

The TIDA-01054 reference design helps eliminate the performance degrading effects of EMI on Data Acquisition (DAQ) systems greater than 16 bits with the help of the LM53635 buck converter. The buck converter enables the designer to place power solutions close to the signal path without the (...)
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-01042 — Modular battery tester reference design for 50-A, 100-A, and 200-A applications

This reference design provides a modular battery test solution allowing users to have the flexibility to test batteries at different current levels with one design. This design leverages the TIDA-01041 reference design by providing two 100-A battery testers that can work independently or be (...)
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-01055 — ADC Voltage Reference Buffer Optimization Reference Design for High Performance DAQ Systems

The TIDA-01055 reference design for high performance DAQ Systems optimizes the ADC reference buffer to improve SNR performance and reduce power consumption with the TI OPA837 high-speed op amp. This device is used in a composite buffer configuration and provides a 22% power improvement over (...)
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-01057 — Reference Design Maximizing Signal Dynamic Range for True 10 Vpp Differential Input to 20 bit ADC

This reference design is designed for high performance data acquisition(DAQ) systems to improve the dynamic range of 20 bit differential input ADCs. Many DAQ systems require the measurement capability at a wide FSR (Full Scale Range) in order to obtain sufficient signal dynamic range. Many earlier (...)
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-01051 — Reference Design Optimizing FPGA Utilization and Data Throughput for Automatic Test Equipment

The TIDA-01051 reference design is used to demonstrate optimized channel density, integration, power consumption, clock distribution and signal chain performance of very high channel count data acquisition (DAQ) systems such as those used in automatic test equipment (ATE). Using serializers, such (...)
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-01050 — Optimized Analog Front End DAQ System Reference Design for 18 bit SAR Data Converters

The TIDA-01050 reference design aims to improve the integration, power consumption, performance, and clocking issues typically associated with automatic test equipment. This design is applicable to any ATE system but most applicable to systems requiring a large number of input channels.
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-01052 — ADC Driver Reference Design Improving Full Scale THD Using Negative Supply

The TIDA-01052 reference design aims to highlight system performance increases seen using a negative voltage rail on the analog front end driver amplifiers rather than ground. This concept is relative to all analog front ends, however this design is aimed specifically at automatic test equipment.
Design guide: PDF
Schematic: PDF
Reference designs

TIPD129 — 0-1A, Single-Supply, Low-Side, Current Sensing Solution

This TI Verified Design implements a single-supply, low-side current sensing solution that can accurately detect load current from 0-1A.  The corresponding linear output range is from 0V to 4.9V. This design relies on the LM7705 inverting charge pump to bias the negative supply of the OPA320 to (...)
User guide: PDF
Schematic: PDF
Reference designs

TIDA-00187 — Extending Rail-to-Rail Output Range for Fully Differential Amplifiers to Include True Zero Volts

Operational amplifiers (op amps) have been used for decades in signal conditioning circuits and measurement systems. An op amp that has an output spanning from negative to positive supply rail are generally referred to as rail-to-rail output (RRO) op amps. These devices have been used increasingly (...)
Design guide: PDF
Schematic: PDF
Package Pins CAD symbols, footprints & 3D models
VSSOP (DGK) 8 Ultra Librarian
TI's Standard Terms and Conditions for Evaluation Items apply.

Ordering & quality

Information included:
  • RoHS
  • REACH
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring
Information included:
  • Fab location
  • Assembly location

Support & training

TI E2E™ forums with technical support from TI engineers

View all forum topics

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​

Videos