SBOS755 October   2016 TLV2376 , TLV376 , TLV4376

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information: TLV376
    5. 6.5 Thermal Information: TLV2376
    6. 6.6 Thermal Information: TLV4376
    7. 6.7 Electrical Characteristics
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Operating Voltage
      2. 7.3.2 Capacitive Load and Stability
      3. 7.3.3 Input Offset Voltage and Input Offset Voltage Drift
      4. 7.3.4 Common-Mode Voltage Range
      5. 7.3.5 Input and ESD Protection
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Operating Characteristics
      2. 8.1.2 Basic Amplifier Configurations
      3. 8.1.3 Active Filtering
      4. 8.1.4 Driving an Analog-to-Digital Converter
      5. 8.1.5 Phantom-Powered Microphone
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 TINA-TI (Free Software Download)
        2. 11.1.1.2 TI Precision Designs
        3. 11.1.1.3 WEBENCH® Filter Designer
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Related Links
    4. 11.4 Receiving Notification of Documentation Updates
    5. 11.5 Community Resources
    6. 11.6 Trademarks
    7. 11.7 Electrostatic Discharge Caution
    8. 11.8 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7 Detailed Description

7.1 Overview

The TLVx376 family belongs to a new generation of low-noise operational amplifiers with e-trim™, giving customers outstanding dc precision and ac performance. Low noise, rail-to-rail input and output, and low offset, drawing a low quiescent current, make these devices ideal for a variety of precision and portable applications. In addition, this family of devices have a wide supply range with excellent PSRR, making the TLVx376 a suitable option for applications that are battery-powered without regulation.

7.2 Functional Block Diagram

TLV376 TLV2376 TLV4376 fbd_bos755.gif

7.3 Feature Description

The TLVx376 family of precision amplifiers offers excellent dc performance as well as excellent ac performance. Operating from a single power supply, the TLVx376 is capable of driving large capacitive loads, has a wide input common-mode voltage range, and is well-suited to drive the inputs of successive-approximation register (SAR) analog-to-digital converters (ADCs) as well as 24-bit and higher resolution converters. All devices feature internal ESD protection. The TLVx376 family is offered in a variety of industry-standard packages for applications that require space savings.

7.3.1 Operating Voltage

The TLVx376 family of amplifiers operate over a power-supply range of 2.2 V to 5.5 V (±1.1 V to ±2.75 V). Many of the specifications apply from –40°C to +125°C. Parameters that can exhibit significant variance with regard to operating voltage or temperature are presented in the Typical Characteristics section.

7.3.2 Capacitive Load and Stability

The TLVx376 series of amplifiers can be used in applications where driving a capacitive load is required. As with all op amps, there can be specific instances where the TLVx376 can become unstable, leading to oscillation. The particular op amp circuit configuration, layout, gain, and output loading are some of the factors to consider when establishing whether an amplifier is stable in operation or not. An op amp in the unity-gain (+1 V/V) buffer configuration and driving a capacitive load exhibits a greater tendency to be unstable than an amplifier operated at a higher noise gain. The capacitive load, in conjunction with the op amp output resistance, creates a pole within the feedback loop that degrades the phase margin. The phase margin reduces when the capacitive loading increases.

7.3.3 Input Offset Voltage and Input Offset Voltage Drift

The TLVx376 family of operational amplifiers is manufactured using TI's e-trim™ technology. Each amplifier is trimmed in production, thereby minimizing errors associated with input offset voltage and input offset voltage drift. The e-trim™ technology is a TI proprietary method of trimming internal device parameters during either wafer probing or final testing.

The TLVx376 in a unity-gain configuration can directly drive up to 250 pF of pure capacitive load. Increasing the gain enhances the ability of the amplifier to drive greater capacitive loads; see Figure 16. In unity-gain configurations, capacitive load drive can be improved by inserting a small (10 Ω to 20 Ω) resistor, RS, in series with the output, as shown in Figure 22. This resistor significantly reduces ringing and maintains dc performance for purely capacitive loads. However, if there is a resistive load in parallel with the capacitive load, a voltage divider is created, introducing a gain error at the output and slightly reducing the output swing. The error introduced is proportional to the ratio RS / RL, and is generally negligible at low output current levels.

TLV376 TLV2376 TLV4376 ai_cap_load_drive_bos755.gif Figure 22. Improving Capacitive Load Drive

7.3.4 Common-Mode Voltage Range

The input common-mode voltage range of the TLVx376 series extends 100 mV beyond the supply rails. The offset voltage of the amplifier is very low, from approximately (V–) to (V+) – 1 V, as shown in Figure 23. The offset voltage increases when common-mode voltage exceeds (V+) –1 V. Common-mode rejection is specified from (V–) to (V+) – 1.3 V.

TLV376 TLV2376 TLV4376 ai_offset_cm_volt_bos406.gif Figure 23. Offset and Common-Mode Voltage

Parameters that can vary across the common-mode voltage range are listed in Table 1.

Table 1. Parameters With Variation Across the Common-Mode Voltage Range

PARAMETER (V–) - 0.1 V < VCM < (V+) – 1.3 V (V+) – 1.3 V < VCM < (V+) + 0.1 V UNIT
TYP TYP
OFFSET VOLTAGE
VOS Input offset voltage 40 2500 μV
dVOS/dT Offset voltage vs temperature 1 25 μV/°C
OPEN LOOP GAIN
AOL Open-loop voltage gain 126 96 dB
INPUT VOLTAGE RANGE
CMRR Common-mode rejection ratio 88 43 dB
FREQUENCY RESPONSE
GBW Gain-bandwidth product 5.5 5.5 MHz
PM Phase margin 72 72 Degrees
SR Slew rate, G = 1 2 1.1 V/μs
NOISE
en Input voltage noise density,
f = 1 kHz		 8 135 nV/√Hz
in Input current noise, f = 1 kHz 2 47 fA/√Hz

7.3.5 Input and ESD Protection

The TLVx376 family incorporates internal electrostatic discharge (ESD) protection circuits on all pins. In the case of input and output pins, this protection primarily consists of current-steering diodes connected between the input and power-supply pins. These ESD protection diodes also provide in-circuit, input overdrive protection, as long as the current is limited to 10 mA as stated in the Absolute Maximum Ratings table. Figure 24 shows how a series input resistor can be added to the driven input to limit the input current. The added resistor contributes thermal noise at the amplifier input. In noise-sensitive applications, the value of this resistor must be as low as possible.

TLV376 TLV2376 TLV4376 ai_input_cur_bos755.gif Figure 24. Input Current Protection

7.4 Device Functional Modes

The TLVx376 family has a single functional mode and is operational when the power-supply voltage is greater than 2.2 V (±1.1 V). The maximum power-supply voltage for the TLVx376 family is 5.5 V (±2.75 V).