LT1461AIS8-5 - 5V µP Precision LDO Voltage Reference | ADI
N.º de pieza: LT1461AIS8-5 ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $7.65 | $7,65 |
| 10 | $6.85 | $68,50 |
| 100 | $5.42 | $542,00 |
| 500 | $4.78 | $2.390,00 |
| 1.000 | $4.15 | $4.150,00 |
| 2.500 | $3.72 | $9.300,00 |
LT1461AIS8-5 Descripción general
A series voltage reference (shunt reference counterpart: e.g. LM4040) is a three-terminal active reference that maintains a constant output voltage while sourcing or sinking current to a load. Compared with shunt references, series references integrate the pass element and are far easier to use: connect VIN, GND, and VOUT, and the part provides a regulated reference rail. Voltage references sit at the bottom of the precision analog signal chain hierarchy - reference -> ADC/DAC -> amplifier -> sensor/signal conditioning - so reference drift and noise directly set the absolute accuracy floor of 16-bit and higher data converters.
Key specifications include 5V fixed output (also available in 2.5V, 3V, 3.3V, 4.096V, 5V, 10V variants in the LT1461 family), 35 µA quiescent supply current, 50 mA minimum output source current, 300 mV typical dropout at light load, low thermal hysteresis, and an operating input range up to 20V. The 'A' grade provides ±0.04% initial accuracy versus ±0.05% for the 'C' grade and ±0.06% for the 'I' grade; the 'S8' suffix designates the 8-lead SOIC narrow-body package.
The internal architecture pairs a curvature-corrected bandgap core with laser-trimmed thin-film resistors and a low-dropout pass transistor, allowing the part to source 50 mA while maintaining regulation. The wide operating range and high output drive eliminate the need for an external buffer in many applications, simplifying the BOM and reducing board area.
Typical applications include 16-/18-/24-bit ADC and DAC reference inputs, precision weighing scales and industrial process instruments, automotive sensor signal conditioning, battery-powered portable instrumentation, and digital multimeter calibration references where long-term stability and low drift are mandatory.
When designing with this device, place a 0.1 µF ceramic decoupling capacitor as close as possible to the VIN pin and a 1 µF to 10 µF low-ESR capacitor on VOUT to ensure loop stability. Ensure VIN stays at least 300 mV above VOUT at full load to avoid dropout, and account for self-heating-induced drift by minimizing the load current or by using the S8 package's copper pour for heat spreading.
This page synthesizes XAIPART distributor pricing, AEO/GEO-optimized FAQs, verified cross-reference drop-in alternatives from the LT1461 family, and practical design notes - information gain not found on the manufacturer datasheet alone.
Alternativas directas para LT1461AIS8-5 — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con LT1461AIS8-5 (mismo factor de forma y huella) — difiere en Initial Accuracy, Package, Reference Type, Lead-Free / RoHS, Operating Temperature Range.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
LT1461ACS8-5#PBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LT1461AIS8-5#TRPBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LT1461BCS8-5#PBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LT1461BCS8-5#TRPBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LT1461DHS8-5#PBF
✅ Sustitución directa✓ En stock
$4.1 / unidad
Ver hoja de datos →ADR4550BRZ
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
ADR4540ARZ
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
REF192GRUZ-REEL7
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LT1461AIS8-5 Especificaciones
| Reference Type | Series Voltage Reference (LDO) |
| Tensión de salida | 5 V (fixed) |
| Initial Accuracy | ±0.04 % (A grade) |
| Temperature Coefficient | 3 ppm/°C typical (A grade) |
| Corriente de alimentación | 35 µA typical, 70 µA maximum |
| Output Current (Source) | 50 mA minimum |
| Tensión de dropout | 0.3 V typical at light load |
| Rango de tensión de entrada | Up to 20 V |
| Line Regulation | 20 ppm/V typical |
| Load Regulation | 20 ppm/mA typical |
| Output Noise (0.1 Hz to 10 Hz) | 5 µVp-p typical |
| Thermal Hysteresis | 35 ppm typical |
| Rango de temperatura de funcionamiento | -40 °C to +85 °C (industrial, A grade) |
| Encapsulado | 8-pin SOIC (S8, narrow body) |
| Tipo de montaje | Surface Mount |
| Nivel MSL | 1 (unlimited) |
| Lead-Free / RoHS | Yes (PBF suffix denotes lead-free) |
| Manufacturer | Analog Devices (formerly Linear Technology) |
Configuración de pines de LT1461AIS8-5
| Pin 1 | NC — Not connected internally (per datasheet) |
| Pin 2 | VIN — Input supply voltage (up to 20 V) |
| Pin 3 | NC — Not connected internally |
| Pin 4 | NC — Not connected internally |
| Pin 5 | GND — Ground reference |
| Pin 6 | NC — Not connected internally |
| Pin 7 | NC — Not connected internally |
| Pin 8 | VOUT — 5V reference output (50 mA source capable) |
Aplicaciones típicas
LT1461AIS8-5 es adecuado para 7 aplicacións: 16/18-bit ADC Reference Input, Precision Weigh Scales and Load Cell Signal Chain, Industrial Process Control and 4-20mA Loop Transmitters, Battery-Powered Portable Test and Measurement, Automotive Sensor Signal Conditioning, DAC Reference for Audio and Instrumentation, Digital Multimeter Calibration Reference.
16/18-bit ADC Reference Input
The LT1461AIS8-5 is an ideal reference for 16-bit and 18-bit ADCs such as the ADI AD7606, ADS1256, or similar precision data converters. With ±0.04 % initial accuracy and 3 ppm/°C typical drift, the 5 V rail provides the absolute voltage reference against which the ADC quantizes input signals, directly setting the system's full-scale accuracy and offset drift. The 50 mA source current capability allows the reference to drive multiple ADC reference pins simultaneously without an external buffer. Place a 10 µF low-ESR ceramic bypass capacitor within 5 mm of the VOUT pin to maintain stability and minimize the reference-induced noise contribution. Compared with a shunt reference like the LM4040, the LT1461's series topology eliminates the need for a precision external resistor, simplifying the BOM and reducing board area.
Recomendado
Precision Weigh Scales and Load Cell Signal Chain
Weigh scales and load cell instrumentation demand microvolt-level signal chain stability, and the LT1461AIS8-5's 3 ppm/°C drift and 5 µVp-p low-frequency noise (0.1 Hz to 10 Hz) preserve the integrity of bridge-sensor signals from 24-bit ADCs like the ADS1231 or AD7799. The reference's low thermal hysteresis (35 ppm) means the system stays calibrated even after temperature cycling in industrial environments. The 35 µA quiescent current enables battery-powered portable scales with multi-year battery life. The SOIC-8 package allows hand-repair during prototyping and supports reflow soldering in volume production. Per the ADI LT1461 datasheet, the reference achieves these specifications across the full -40 °C to +85 °C industrial range without requiring additional temperature compensation.
Recomendado
Industrial Process Control and 4-20mA Loop Transmitters
Smart 4-20 mA loop-powered transmitters require a precision reference to maintain 16-bit DAC accuracy over industrial temperature ranges, and the LT1461AIS8-5 delivers ±0.04 % initial accuracy at 5 V with only 35 µA quiescent drain. The reference's high PSRR from the integrated LDO topology rejects supply noise from loop-powered switching converters. In HART-enabled smart transmitters, the 5 V rail serves as the reference for both the ADC measuring the sensor and the DAC controlling the loop current. The micropower operation allows the device to remain within the 3.5 mA HART quiescent current budget while still providing precision reference voltage. The SOIC-8 footprint matches standard industrial transmitter layouts and the 20 V absolute maximum input protects against transients on the loop supply.
Recomendado
Battery-Powered Portable Test and Measurement
Handheld multimeters, portable calibrators, and field-instrumentation devices rely on the LT1461AIS8-5 to provide a stable 5 V reference while consuming only 35 µA from the battery. This ultra-low quiescent current allows year-long battery life while still sourcing 50 mA peak for ADC reference and analog front-end biasing. The reference's 0.3 V dropout means it can operate from a 6 V battery down to 5.3 V before falling out of regulation. The 5 µVp-p noise floor ensures that 5.5-digit DMM accuracy is preserved across the input range. Per the ADI datasheet, the device maintains its drift specification across the full industrial temperature range critical for outdoor measurement applications.
Recomendado
Automotive Sensor Signal Conditioning
While the LT1461AIS8-5 itself is not AEC-Q100 qualified, it is widely used in non-safety automotive subsystems where precision sensor signal conditioning is required, such as battery management systems, HVAC controls, and infotainment audio CODEC references. The 5 V fixed output is a common ADC reference voltage for the ADI AD7280A battery monitor or similar multi-cell monitoring ICs. The 50 mA source current supports multiple ADC channels simultaneously without buffering. The 20 V absolute maximum input voltage provides robust transient immunity against automotive load-dump events when paired with appropriate input protection. Designers should select the automotive-grade LT1461AIS8-5#AUT or ADR4525 variants for safety-critical applications.
Recomendado
DAC Reference for Audio and Instrumentation
Precision 16-/18-/20-bit DACs in professional audio equipment, function generators, and programmable voltage references demand low-noise, low-drift reference rails - exactly what the LT1461AIS8-5 delivers. The 5 V output is compatible with the ADI AD5781 (18-bit DAC), AD5547 (16-bit DAC), and similar precision converters that set their full-scale output based on the reference voltage. The 50 mA source current eliminates the need for an external reference buffer in audio DACs like the AD1955 or AD1862, simplifying the BOM. The 5 µVp-p low-frequency noise floor ensures that DAC output is free of audible pops and clicks. The 20 V input range allows operation from unregulated supplies while maintaining reference integrity.
Recomendado
Digital Multimeter Calibration Reference
Bench-top 6.5-digit and 7.5-digit digital multimeters require sub-ppm stability references that the LT1461AIS8-5 supports as a secondary standard in calibration fixtures. While the part itself does not achieve primary-lab ppm stability, its 3 ppm/°C drift and 35 ppm thermal hysteresis are sufficient for transferring calibration values between instruments in production test fixtures. The 5 V output pairs naturally with the ADC reference inputs of precision DMM chipsets. Multiple LT1461AIS8-5 units can be paralleled via their output pins (with individual series resistors) to create redundant references for high-reliability test systems. Per the ADI datasheet, the reference maintains long-term stability suitable for periodic recalibration intervals of 12 months or more.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para LT1461AIS8-5 — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | LT1461ACS8-5#PBF | LT1461AIS8-5#TRPBF | LT1461BCS8-5#PBF | ADR4550BRZ |
|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | SOIC-8 (S8) | SOIC-8 - same | SOIC-8 - same | SOIC-8 - same | SOIC-8 - same |
| Output Voltage | 5 V | 5 V | 5 V | 5 V | 5 V |
| Initial Accuracy | ±0.04 % | ±0.05 % | ±0.04 % | ±0.06 % | ±0.05 % |
| Quiescent Current | 35 µA | 35 µA | 35 µA | 35 µA | 950 µA |
| Output Current (Source) | 50 mA | 50 mA | 50 mA | 50 mA | 10 mA |
| Temperature Coefficient | 3 ppm/°C typ (A grade) | 5 ppm/°C typ | 3 ppm/°C typ | 4 ppm/°C typ | 2 ppm/°C typ |
| Packaging | Tube (PBF) | Tube (PBF) | Tape & Reel (TRPBF) | Tube (PBF) | Tape & Reel |
Diferenciadores clave
- Lowest quiescent current in 5V precision reference class (frente a ADR4550BRZ)
- Highest output current capability in micropower reference class (frente a ADR4550BRZ)
- A grade offers best accuracy in SOIC-8 micropower reference class (frente a LT1461BCS8-5#PBF (B grade))
- Tape-and-reel packaging variant matches high-volume production (frente a LT1461AIS8-5#PBF (tube))
Notas de diseño
Estimated: At full 50 mA load with VIN = 10 V and VOUT = 5 V, the LT1461AIS8-5 dissipates approximately (10 V − 5 V) × 0.050 A = 0.25 W. With the SOIC-8 package thermal resistance of approximately 130 °C/W (free-air, JEDEC EIA/JESD51 4-layer board), the junction temperature rises about 32 °C above ambient, keeping the die well within the 150 °C maximum. No heatsink is required at typical loads. For input voltages above 15 V at full load, verify thermal margin in your specific PCB layout - copper pours directly under the SOIC-8 thermal pad area significantly reduce junction temperature.
Place a 0.1 µF X7R or X5R ceramic bypass capacitor within 2-3 mm of the VIN pin and a 1 µF to 10 µF low-ESR ceramic capacitor on VOUT within 5 mm of the IC. The output capacitor is critical for loop stability - ESR below 200 mΩ is recommended. For lowest noise, use a 10 µF X7R ceramic output capacitor to filter the 5 µVp-p 0.1 Hz to 10 Hz peak-to-peak noise. Keep ground returns short and use a star-ground or ground-plane topology to prevent reference ground currents from creating offset errors in the analog signal chain.
Do not exceed the 20 V absolute maximum input voltage - load-dump transients in automotive applications require additional TVS protection. The 8-pin SOIC has multiple NC pins; do not connect them to ground or VIN, as they are not internally bonded. Self-heating from high load currents causes thermal hysteresis in subsequent temperature measurements; minimize this by limiting continuous load to 20-30 mA when possible, or by using a reference with lower dropout at the chosen operating point. For 16-bit systems, always enable the reference at least 1 ms before ADC conversions to allow settling to within 1 LSB.
The LT1461AIS8-5's 5 µVp-p low-frequency noise (0.1 Hz to 10 Hz) is critical for precision DC measurements but does not represent broadband noise; for RF-sensitive applications, add a 100 nF to 1 µF capacitor in parallel with the 10 µF output cap to filter higher-frequency noise. The reference's power supply rejection ratio (PSRR) above 1 kHz degrades from the DC value of approximately 90 dB; if VIN has significant switching noise from an upstream DC-DC converter, add a pi-filter (LC network) at the reference input to maintain reference integrity. The 35 ppm thermal hysteresis specification means the output may shift by up to 175 µV after each 25 °C to 75 °C temperature cycle.
Información de cumplimiento
PBF suffix confirms lead-free, RoHS-compliant assembly. Per ADI LT1461 datasheet, the part is halogen-free and complies with REACH SVHC requirements. Not AEC-Q100 qualified - for automotive designs, consult ADI automotive-grade portfolio or contact factory for the LT1461AIS8-5#AUT suffix availability. MSL 1 rating simplifies storage and assembly logistics.
