The OPA376 family represents a new generation of low-noise operational amplifiers with e-trim™, offering outstanding dc precision and ac performance. Rail-to-rail input and output, low offset (25 μV, maximum), low noise (7.5 nV/√Hz), quiescent current of 950 μA (maximum), and a 5.5-MHz bandwidth make this part very attractive for a variety of precision and portable applications. In addition, this device has a reasonably wide supply range with excellent PSRR, making it attractive for applications that run directly from batteries without regulation.
The OPA376 (single version) is available in MicroSIZE SC70-5, SOT-23-5, and SOIC-8 packages. The OPA2376 (dual) is offered in the DSBGA-8, VSSOP-8, and SOIC-8 packages. The OPA4376 (quad) is offered in a TSSOP-14 package. All versions are specified for operation from –40°C to +125°C.
PART NUMBER | PACKAGE | BODY SIZE (NOM) |
---|---|---|
OPA376 | SOIC (8) | 4.90 mm × 3.91 mm |
SOT-23 (5) | 2.90 mm × 1.60 mm | |
SC70 (5) | 2.00 mm × 1.25 mm | |
OPA2376 | SOIC (8) | 4.90 mm × 3.91 mm |
VSSOP (8) | 3.00 mm × 3.00 mm | |
DSBGA (8) | 1.30 mm × 2.30 mm | |
OPA4376 | TSSOP (14) | 5.00 mm × 4.40 mm |
Changes from F Revision (March 2013) to G Revision
Changes from E Revision (January 2013) to F Revision
Changes from D Revision (August 2010) to E Revision
Changes from C Revision (October 2008) to D Revision
PIN | I/O | DESCRIPTION | |||
---|---|---|---|---|---|
NAME | DBV | DCK | D | ||
+IN | 3 | 1 | 3 | I | Input signal + |
–IN | 4 | 3 | 2 | I | Input signal – |
NC | — | — | 1, 5, 8 | — | No connection |
OUT | 1 | 4 | 6 | O | Output signal |
V+ | 5 | 5 | 7 | — | Supply voltage+ |
V– | 2 | 2 | 4 | — | Supply voltage– |
PIN | I/O | DESCRIPTION | ||
---|---|---|---|---|
NAME | D AND DGK | YZD | ||
+IN A | 3 | C1 | I | Input signal A+ |
–IN A | 2 | B1 | I | Input signal A– |
+IN B | 5 | D2 | I | Input signal B+ |
–IN B | 6 | C2 | I | Input signal B– |
OUT A | 1 | A1 | O | Output signal A |
OUT B | 7 | B2 | O | Output signal B |
V+ | 8 | A2 | — | Supply voltage+ |
V– | 4 | D1 | — | Supply voltage– |
PIN | I/O | DESCRIPTION | |
---|---|---|---|
NAME | PW | ||
+IN A | 3 | I | Input signal A+ |
–IN A | 2 | O | Input signal A– |
+IN B | 5 | I | Input signal B+ |
–IN B | 6 | O | Input signal B– |
+IN C | 10 | I | Input signal C+ |
–IN C | 9 | O | Input signal C– |
+IN D | 12 | I | Input signal D+ |
–IN D | 13 | O | Input signal D– |
OUT A | 1 | O | Output signal A |
OUT B | 7 | O | Output signal B |
OUT C | 8 | O | Output signal C |
OUT D | 14 | O | Output signal D |
V+ | 4 | — | Supply voltage+ |
V– | 11 | — | Supply voltage– |
MIN | MAX | UNIT | ||
---|---|---|---|---|
Voltage | Supply, VS = (V+) – (V–) | 7 | V | |
Signal input pin(2) | (V–) – 0.5 | (V+) + 0.5 | V | |
Current | Signal input pin(2) | –10 | 10 | mA |
Output short-circuit(3) | Continuous | |||
Temperature | Operating range, TA | –40 | 150 | °C |
Junction, TJ | 150 | |||
Storage, Tstg | –65 | 150 |
VALUE | UNIT | |||
---|---|---|---|---|
V(ESD) | Electrostatic discharge | Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all pins(1) | ±4000 | V |
Charged device model (CDM), per JEDEC specification JESD22-C101, all pins(2) | ±1000 | |||
Machine model | ±200 |
MIN | NOM | MAX | UNIT | ||
---|---|---|---|---|---|
(V+) – (V–) | Supply voltage | 2.2 (±1.1) | 5.5 (±2.75) | V | |
TA | Operating temperature | –40 | 150 | °C |
THERMAL METRIC(1) | OPA376 | UNIT | |||
---|---|---|---|---|---|
DBV (SOT-23) | DCK (SC70) | D (SOIC) | |||
5 PINS | 5 PINS | 8 PINS | |||
RθJA | Junction-to-ambient thermal resistance | 273.8 | 267.0 | 100.1 | °C/W |
RθJC(top) | Junction-to-case (top) thermal resistance | 126.8 | 80.9 | 42.4 | °C/W |
RθJB | Junction-to-board thermal resistance | 85.9 | 54.8 | 41.0 | °C/W |
ψJT | Junction-to-top characterization parameter | 10.9 | 1.2 | 4.8 | °C/W |
ψJB | Junction-to-board characterization parameter | 84.9 | 54.1 | 40.3 | °C/W |
RθJC(bot) | Junction-to-case (bottom) thermal resistance | n/a | n/a | n/a | °C/W |
THERMAL METRIC(1) | OPA2376 | UNIT | |||
---|---|---|---|---|---|
D (SOIC) | DGK (VSSOP) | YZD (DSBGA) | |||
8 PINS | 8 PINS | 8 PINS | |||
RθJA | Junction-to-ambient thermal resistance | 111.1 | 171.2 | 119.2 | °C/W |
RθJC(top) | Junction-to-case (top) thermal resistance | 54.7 | 63.9 | 0.6 | °C/W |
RθJB | Junction-to-board thermal resistance | 51.7 | 92.8 | 27.6 | °C/W |
ψJT | Junction-to-top characterization parameter | 10.5 | 9.2 | 4.0 | °C/W |
ψJB | Junction-to-board characterization parameter | 51.2 | 91.2 | 27.6 | °C/W |
RθJC(bot) | Junction-to-case (bottom) thermal resistance | n/a | n/a | n/a | °C/W |
THERMAL METRIC(1) | OPA4376 | UNIT | |
---|---|---|---|
PW | |||
14 PINS | |||
RθJA | Junction-to-ambient thermal resistance | 107.8 | °C/W |
RθJC(top) | Junction-to-case (top) thermal resistance | 29.6 | °C/W |
RθJB | Junction-to-board thermal resistance | 52.6 | °C/W |
ψJT | Junction-to-top characterization parameter | 1.5 | °C/W |
ψJB | Junction-to-board characterization parameter | 51.6 | °C/W |
RθJC(bot) | Junction-to-case (bottom) thermal resistance | n/a | °C/W |
PARAMETER | TEST CONDITIONS | MIN | TYP | MAX | UNIT | ||
---|---|---|---|---|---|---|---|
OFFSET VOLTAGE | |||||||
VOS | Input offset voltage | 5 | 25 | μV | |||
dVOS/dT | Input offset voltage versus temperature | TA = –40°C to +85°C | 0.26 | 1 | μV/°C | ||
TA = –40°C to +125°C | 0.32 | 2 | μV/°C | ||||
PSRR | Input offset voltage versus power supply | TA = 25°C, VS = 2.2 V to 5.5 V, VCM < (V+) – 1.3 V | 5 | 20 | μV/V | ||
TA = –40°C to +125°C, VS = 2.2 V to 5.5 V, VCM < (V+) – 1.3 V |
5 | μV/V | |||||
Channel separation, dc (dual, quad) | 0.5 | mV/V | |||||
INPUT BIAS CURRENT | |||||||
IB | Input bias current | TA = 25°C | 0.2 | 10 | pA | ||
TA = –40°C to +125°C | See Typical Characteristics | pA | |||||
IOS | Input offset current | 0.2 | 10 | pA | |||
NOISE | |||||||
Input voltage noise | f = 0.1 Hz to 10 Hz | 0.8 | μVPP | ||||
en | Input voltage noise density | f = 1 kHz | 7.5 | nV/√Hz | |||
in | Input current noise | f = 1 kHz | 2 | fA/√Hz | |||
INPUT VOLTAGE RANGE | |||||||
VCM | Common-mode voltage range | (V–) – 0.1 | (V+) + 0.1 | V | |||
CMRR | Common-mode rejection ratio | (V–) < VCM < (V+) – 1.3 V | 76 | 90 | dB | ||
INPUT CAPACITANCE | |||||||
Differential | 6.5 | pF | |||||
Common-mode | 13 | pF | |||||
OPEN-LOOP GAIN | |||||||
AOL | Open-loop voltage gain | 50 mV < VO < (V+) – 50 mV, RL = 10 kΩ | 120 | 134 | dB | ||
100 mV < VO < (V+) – 100 mV, RL = 2 kΩ | 120 | 126 | dB | ||||
FREQUENCY RESPONSE CL = 100 pF, VS = 5.5 V | |||||||
GBW | Gain-bandwidth product | 5.5 | MHz | ||||
SR | Slew rate | G = 1 | 2 | V/μs | |||
tS | Settling time | To 0.1%, 2-V step , G = 1 | 1.6 | μs | |||
To 0.01%, 2-V step , G = 1 | 2 | μs | |||||
Overload recovery time | VIN × gain > VS | 0.33 | μs | ||||
THD+N | Total harmonic distortion + noise | VO = 1 VRMS, G = 1, f = 1 kHz, RL = 10 kΩ | 0.00027% | ||||
OUTPUT | |||||||
Voltage output swing from rail | TA = 25°C, RL = 10 kΩ | SC70-5, SOT23-5, SO-8, VSSOP-8, and TSSOP-14 packages only | 10 | 20 | mV | ||
DSBGA package only | 20 | 30 | mV | ||||
TA = –40°C to +125°C, RL = 10 kΩ | 40 | mV | |||||
TA = 25°C, RL = 2 kΩ | SC70-5, SOT23-5, SO-8, VSSOP-8, and TSSOP-14 packages only | 40 | 50 | mV | |||
DSBGA package only | 50 | 60 | mV | ||||
TA = –40°C to +125°C, RL = 2 kΩ | 80 | mV | |||||
ISC | Short-circuit current | +30, –50 | mA | ||||
CLOAD | Capacitive load drive | See Typical Characteristics | |||||
RO | Open-loop output impedance | 150 | Ω | ||||
POWER SUPPLY | |||||||
VS | Specified voltage range | 2.2 | 5.5 | V | |||
Operating voltage range | 2 to 5.5 | V | |||||
IQ | Quiescent current per amplifier | TA = 25°C, IO = 0, VS = 5.5 V, VCM < (V+) – 1.3 V | 760 | 950 | μA | ||
TA = –40°C to +125°C | 1 | mA | |||||
TEMPERATURE | |||||||
Specified range | –40 | 125 | °C | ||||
Operating range | –40 | 150 | °C |
The OPA376 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 device has a wide supply range with excellent PSRR, making it a suitable option for applications that are battery-powered without regulation.
The OPAx376 family of precision amplifiers offers excellent dc performance as well as excellent ac performance. Operating from a single power-supply the OPAx376 is capable of driving large capacitive loads, has a wide input common-mode voltage range, and is well-suited to drive the inputs of SAR ADCs as well as 24-bit and higher resolution converters. Including internal ESD protection, the OPAx376 family is offered in a variety of industry-standard packages, including a wafer chip-scale package for applications that require space savings.
The OPA376 family of amplifiers operates 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.
The OPAx376 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 OPA376 series of amplifiers may be used in applications where driving a capacitive load is required. As with all op amps, there may be specific instances where the OPAx376 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 will be stable in operation. 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 degradation of the phase margin increases as the capacitive loading increases.
The OPAx376 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 the typical characteristic 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 while maintaining 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.
The input common-mode voltage range of the OPA376 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 as common-mode voltage exceeds (V+) –1 V. Common-mode rejection is specified from (V–) to (V+) – 1.3 V.
The OPA376 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. Figure 24 shows how a series input resistor may be added to the driven input to limit the input current. The added resistor contributes thermal noise at the amplifier input and its value should be kept to a minimum in noise-sensitive applications.
The OPAx376 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 OPAx376 is 5.5 V (±2.75 V).
NOTE
Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality.
The OPA376 family of operational amplifiers is built using e-trim, a proprietary technique in which offset voltage is adjusted during the final steps of manufacturing. This technique compensates for performance shifts that can occur during the molding process. Through e-trim, the OPA376 family delivers excellent offset voltage (5 μV, typical). Additionally, the amplifier boasts a fast slew rate, low drift, low noise, and excellent PSRR and AOL. These 5.5-MHz CMOS op amps operate on 760-μA (typical) quiescent current.
The OPA376 family is unity-gain stable. It does not exhibit output phase inversion when the input is overdriven. A typical single-supply connection is shown in Figure 25. The OPA376 is configured as a basic inverting amplifier with a gain of –10 V/V. This single-supply connection has an output centered on the common-mode voltage, VCM. For the circuit shown, this voltage is 2.5 V, but may be any value within the common-mode input voltage range.
The OPA376 series is well-suited for filter applications requiring a wide bandwidth, fast slew rate, low-noise, single-supply operational amplifier. Figure 26 shows a 50-kHz, 2nd-order, low-pass filter. The components have been selected to provide a maximally-flat Butterworth response. Beyond the cutoff frequency, roll-off is –40 dB/decade. The Butterworth response is ideal for applications requiring predictable gain characteristics such as the anti-aliasing filter used ahead of an analog-to-digital converter (ADC).
The low noise and wide gain bandwidth of the OPA376 family make it an ideal driver for ADCs. Figure 27 illustrates the OPA376 driving an ADS8327, a 16-bit, 250-kSPS converter. The amplifier is connected as a unity-gain, non-inverting buffer.
The circuit shown in Figure 28 depicts how a remote microphone amplifier can be powered by a phantom source on the output side of the signal cable. The cable serves double duty, carrying both the differential output signal from and dc power to the microphone amplifier stage.
An OPA2376 serves as a single-ended input to a differential output amplifier with a 6-dB gain. Common-mode bias for the two op amps is provided by the dc voltage developed across the electret microphone element. A
48-V phantom supply is reduced to 5.1 V by the series 6.8-kΩ resistors on the output side of the cable, and the 4.7-kΩ resistor and zener diode on the input side of the cable. AC coupling blocks the different dc voltage levels from each other on each end of the cable.
An INA163 instrumentation amplifier provides differential inputs and receives the balanced audio signals from the cable. The INA163 gain may be set from 0 dB to 80 dB by selecting the RG value. The INA163 circuit is typical of the input circuitry used in mixing consoles.
NOINDENT:
Electret microphone powered by R1.Low-pass filters are commonly employed in signal processing applications to reduce noise and prevent aliasing. The OPA376 is ideally suited to construct high-speed, high-precision active filters. Figure 30 shows a second-order, low-pass filter commonly encountered in signal processing applications.
Use the following parameters for this design example:
The infinite-gain multiple-feedback circuit for a low-pass network function is shown in Figure 30. Use Equation 1 to calculate the voltage transfer function.
This circuit produces a signal inversion. For this circuit, the gain at dc and the low-pass cutoff frequency are calculated by Equation 2:
Software tools are readily available to simplify filter design. WEBENCH® Filter Designer is a simple, powerful, and easy-to-use active filter design program. The WEBENCH Filter Designer lets you create optimized filter designs using a selection of TI operational amplifiers and passive components from TI's vendor partners.
Available as a web based tool from the WEBENCH® Design Center, WEBENCH® Filter Designer allows you to design, optimize, and simulate complete multistage active filter solutions within minutes.
The OPAx376 are specified for operation from 2.2 V to 5.5 V (±1.1 V to ±2.75 V); many 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.