LTC2391HLX-16 - 16-Bit 250ksps SAR ADC | Analog Devices
N.º de pieza: LTC2391HLX-16 ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $27.5 | $27,50 |
| 10 | $25.1 | $251,00 |
| 100 | $22.4 | $2.240,00 |
| 500 | $19.95 | $9.975,00 |
| 1.000 | $17.8 | $17.800,00 |
LTC2391HLX-16 Descripción general
A SAR ADC is a type of analog-to-digital converter that performs a binary search through an internal capacitive DAC to determine the digital output code one bit at a time per conversion clock. SAR ADCs combine low latency, deterministic throughput, and excellent noise performance, making them the preferred topology for multiplexed data acquisition, motor control feedback loops, and precision instrumentation. Within the broader taxonomy, the LTC2391HLX-16 belongs to the precision ADC -> data converter -> signal chain IC family of mixed-signal semiconductors.
Key features include 16-bit no-missing-codes performance, 94 dB SNR, ±4.096 V true-differential inputs, integrated reference and reference buffer, and selectable parallel or serial (SPI-compatible) interface. The internal 4.096 V reference is trimmed for low drift, eliminating external reference components in many designs. The wide common-mode input range and high common-mode rejection allow direct connection to bridge sensors, current shunts, and high-impedance signal sources without active front-end conditioning.
Architecturally, the LTC2391HLX-16 uses a charge-redistribution capacitive DAC and on-chip calibration to achieve INL of ±1 LSB and excellent DC accuracy. Its single-shot and burst conversion modes allow trade-offs between latency and channel density. Compared with delta-sigma ADCs of similar noise, it offers dramatically lower latency (one conversion period versus many oversampling cycles), which simplifies system timing in closed-loop control.
Typical applications include industrial process control, weigh scales, instrumentation, motor control current sensing, multiplexed data acquisition systems, and precision sensor signal chains. The differential ±4.096 V range maps cleanly to ±10 V reduced inputs and 4 mA-to-20 mA loop-powered sensor outputs.
When designing with this part, observe the analog and digital ground separation recommended in the datasheet typical application, keep analog input traces short and symmetric, and bypass both AVDD and DVDD with 10 µF ceramic plus 0.1 µF decoupling placed as close as possible to the supply pins.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives from the same Linear Technology/Analog Devices 2391 family, and practical design notes that complement, but do not replace, the manufacturer's datasheet.
Alternativas directas para LTC2391HLX-16 — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
LTC2391CLX-16#PBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LTC2391ILX-16#PBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LTC2391HLX-16#PBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LTC2344CUH-18#PBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LTC2335HLX-16#PBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LTC2391HLX-16 Valores máximos y características eléctricas
| Resolución | 16 bits |
| Architecture | SAR (Successive Approximation Register) |
| Sample Rate | 250 ksps |
| Number of Input Channels | 1 differential |
| Input Range | ±4.096 V fully differential |
| Supply Voltage (AVDD) | 5 V (single supply) |
| Digital I/O Supply (DVDD/OVDD) | 2.5 V to 5 V |
| SNR | 94 dB |
| Internal Reference | 4.096 V (yes, integrated) |
| Reference Buffer | Yes, integrated |
| Interfaz | Parallel / SPI-compatible serial |
| Encapsulado | 48-LQFP (7x7 mm) |
| Operating Temperature Range (H grade) | -40C to +125C |
| Temperature Grade | Automotive H grade |
| RoHS / Lead-Free | Yes (#PBF suffix, RoHS compliant) |
| Throughput Latency | 1 conversion cycle (SAR deterministic) |
Configuración de pines de LTC2391HLX-16
| Pin 1 | AIN+ — Positive differential analog input |
| Pin 2 | AIN- — Negative differential analog input |
| Pin 3 | REF — Reference decoupling / external reference input |
| Pin 4 | REFOUT — Internal 4.096 V reference output |
| Pin 5 | COM — Common-mode reference (mid-scale) |
| Pin 6 | GND — Analog ground |
| Pin 7 | AVDD — Analog 5V supply |
| Pin 8 | AVDD — Analog 5V supply (2nd pin) |
| Pin 9 | DVDD — Digital core supply |
| Pin 10 | OVDD — Digital I/O supply (2.5V-5V) |
| Pin 11 | GND — Digital ground |
| Pin 12 | /CS — Chip select, active low |
| Pin 13 | /RD — Read enable, active low |
| Pin 14 | /CONVST — Conversion start, active low |
| Pin 15 | BUSY — Conversion in progress indicator |
| Pin 16 | D15 — Parallel data output, MSB |
| Pin 17 | D14 — Parallel data output |
| Pin 18 | D13 — Parallel data output |
| Pin 19 | D12 — Parallel data output |
| Pin 20 | D11 — Parallel data output |
| Pin 21 | D10 — Parallel data output |
| Pin 22 | D9 — Parallel data output |
| Pin 23 | D8 — Parallel data output |
| Pin 24 | D7 — Parallel data output |
| Pin 25 | D6 — Parallel data output |
| Pin 26 | D5 — Parallel data output |
| Pin 27 | D4 — Parallel data output |
| Pin 28 | D3 — Parallel data output |
| Pin 29 | D2 — Parallel data output |
| Pin 30 | D1 — Parallel data output |
| Pin 31 | D0 — Parallel data output, LSB |
| Pin 32 | SDO — Serial data output (SPI mode) |
| Pin 33 | SCK — Serial clock input (SPI mode) |
| Pin 34 | /CNV — Conversion control, serial mode |
| Pin 35 | GND — Digital ground |
| Pin 36 | OGND — Digital I/O ground |
| Pin 37 | NC — Not connected (per datasheet) |
| Pin 38 | NC — Not connected (per datasheet) |
| Pin 39 | NC — Not connected (per datasheet) |
| Pin 40 | NC — Not connected (per datasheet) |
| Pin 41 | AVDD — Analog 5V supply (3rd pin) |
| Pin 42 | GND — Analog ground |
| Pin 43 | REFBUF — Reference buffer output |
| Pin 44 | REFIN — Reference input to buffer |
| Pin 45 | AVDD — Analog 5V supply (4th pin) |
| Pin 46 | GND — Analog ground |
| Pin 47 | GND — Analog ground (substrate) |
| Pin 48 | GND — Analog ground (substrate) |
Aplicaciones típicas
LTC2391HLX-16 es adecuado para 6 aplicacións: Industrial Process Control and Weigh Scales, Precision Data Acquisition Systems, Motor Control Current Sensing, Medical and Analytical Instrumentation, Automotive Sensor Signal Chains, Test and Measurement Equipment.
Industrial Process Control and Weigh Scales
The LTC2391HLX-16's 94 dB SNR, ±4.096 V differential input range, and 250 ksps throughput make it ideal for industrial weigh scales and process-control front ends. The ADC's true-differential inputs connect directly to bridge strain-gauge and load-cell outputs, while the integrated 4.096 V reference eliminates external reference drift errors that dominate long-term scale accuracy. Its 1-conversion-cycle SAR latency ensures the deterministic timing required for closed-loop batching controllers, and the H-grade -40C to +125C temperature range tolerates factory-floor thermal stress without derating. Compared with 24-bit sigma-delta ADCs at the same throughput, the LTC2391HLX-16 offers lower latency and simpler digital filtering, accelerating system response in fast-loop process applications.
Recomendado
Precision Data Acquisition Systems
Multiplexed precision data acquisition cards benefit from the LTC2391HLX-16's wide differential input range and integrated reference buffer, which simplify per-channel signal conditioning. The 250 ksps sampling rate supports audio-bandwidth acquisition when paired with appropriate anti-alias filters, while the 16-bit no-missing-codes performance guarantees monotonicity across the full input range - critical for instrumentation calibration tables. The selectable parallel or SPI-compatible serial output lets designers route data directly to an FPGA/CPLD in high-speed systems or to a microcontroller in low-pin-count designs. Reference the LTC2391-16 datasheet typical application circuit for a complete 4-channel muxed front-end using this ADC plus a precision mux such as the ADG1401.
Recomendado
Motor Control Current Sensing
Three-phase motor control loops require deterministic, low-latency current feedback to compute PWM duty cycles within microseconds. The LTC2391HLX-16's SAR architecture completes each conversion in 4 µs (1/250 ksps), so two or three ADCs operating in lock-step can sample all phase currents simultaneously with minimal software latency. The ±4.096 V differential input range maps directly to ±10 A or ±20 A shunt-resistor voltages after scaling, simplifying the analog front end. The H-grade temperature rating suits under-hood industrial motor-drive environments where ambient temperatures exceed 85C. Engineers should place the current-sense shunt within 5 cm of the ADC inputs to limit ground-loop pickup and use the LTC2391-16 datasheet PCB layout guidelines.
Recomendado
Medical and Analytical Instrumentation
Benchtop medical analyzers, spectrophotometers, and laboratory instrumentation demand 16-bit dynamic range with low-latency sampling. The LTC2391HLX-16's 94 dB SNR delivers 15+ ENOB across the audio band, supporting analytical instrument sensitivities for chemiluminescence, electrochemical, and optical-density measurements. The internal reference buffer eliminates the need for an external low-noise reference IC, reducing BOM cost and board area in space-constrained benchtop instruments. Differential ±4.096 V inputs connect directly to instrumentation amplifiers or transimpedance stages for photodiode arrays. The 48-LQFP package is compatible with lead-free reflow profiles required by IEC 60601 medical device assembly standards.
Recomendado
Automotive Sensor Signal Chains
The LTC2391HLX-16's H-grade temperature rating (-40C to +125C) makes it well-suited for automotive sensor interfaces, although it is not itself AEC-Q100 qualified. Engineers building non-safety automotive systems such as battery management, body-control modules, and HVAC controls can use this ADC to digitize pressure, position, and current-sense signals with deterministic SAR latency. The wide ±4.096 V differential range accepts the scaled outputs of bridge sensors used in pedal, throttle, and suspension-position applications. Designers targeting AEC-Q100 systems should consult Analog Devices' automotive-grade ADC families separately. The 5 V single-supply operation aligns with 12 V automotive rails after a simple LDO regulator step-down.
Recomendado
Test and Measurement Equipment
Bench-top DMMs, oscilloscope front-end digitizers, and arbitrary waveform generator feedback loops require a SAR ADC that delivers high linearity and low noise without sigma-delta's long settling time. The LTC2391HLX-16's 1-conversion-cycle SAR latency, 16-bit no-missing-codes performance, and parallel data output port are well matched to FPGA-based DSP back-ends used in modern test equipment. The ±4.096 V differential input range allows direct digitization of ±10 V inputs after simple resistor-attenuator scaling. The internal 4.096 V reference simplifies production calibration since trimming loops can compensate for the well-specified reference tolerance, reducing factory test time and improving long-term measurement repeatability.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para LTC2391HLX-16 — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | LTC2391CLX-16#PBF | LTC2391ILX-16#PBF | LTC2391HLX-16#PBF | LTC2344CUH-18#PBF | LTC2335HLX-16#PBF |
|---|---|---|---|---|---|---|
| Package | 48-LQFP (7x7 mm) | 48-LQFP (7x7 mm) - same | 48-LQFP (7x7 mm) - same | 48-LQFP (7x7 mm) - same | 48-LQFP equivalent footprint family | 48-LQFP (7x7 mm) - same |
| Brand | Analog Devices (Linear Technology) | Analog Devices - same | Analog Devices - same | Analog Devices - same | Analog Devices - same | Analog Devices - same |
| Resolution | 16 bits | 16 bits - same | 16 bits - same | 16 bits - same | 18 bits (+2 LSB) | 16 bits - same |
| Temperature Grade | H: -40C to +125C | C: 0C to +70C (commercial) | I: -40C to +85C (industrial) | H: -40C to +125C - same | C grade | H grade - same |
| Interface | Parallel / SPI serial | Parallel / SPI serial - same | Parallel / SPI serial - same | Parallel / SPI serial - same | SPI/parallel family | SPI |
Diferenciadores clave
- Best-in-class 16-bit SAR with 94 dB SNR at 250 ksps (frente a LTC2389ILX-16)
- Wide ±4.096 V differential input range eliminates front-end attenuation (frente a LTC2361ITS8 (12-bit ADC))
- Pin-compatible across H/I/C temperature grades with identical electrical specs (frente a LTC2391CLX-16#PBF)
Notas de diseño
Separate analog and digital ground planes are mandatory for the LTC2391HLX-16 to achieve the 94 dB SNR specification. Connect AGND and DGND at a single point near the ADC's GND pin (pin 11 in the typical layout). Place 10 µF X7R ceramic + 0.1 µF decoupling pairs on every AVDD and DVDD pin within 3 mm of the pad. Keep analog input traces short, symmetric, and routed away from digital outputs (D0-D15) to minimize digital coupling. Estimated: input-bandwidth 250 ksps / settling 4 µs requires trace lengths under 25 mm to avoid sampling errors.
Route the differential AIN+ and AIN+ traces as a length-matched pair with 50 Ω characteristic impedance and place the common-mode bypass capacitor directly on the COM pin. Use a guard ring tied to COM around the analog input pads to absorb stray leakage currents from PCB contamination. The exposed thermal pad (LQFP-48 paddle) should be soldered to a star-grounded copper pour for thermal dissipation and electrical reference stability, even though the LQFP has no formal thermal-slug requirement. Avoid routing switching power converter traces under the ADC input path.
Do not exceed the absolute maximum AVDD of 5.5 V or OVDD of 5.5 V - over-voltage permanently damages the input ESD structures. Do not operate with OVDD > AVDD, which can forward-bias internal clamps. The internal reference REFOUT requires a 10 µF X7R bypass; using smaller or Y5V dielectrics degrades SNR and INL. Sampling-glitch kickback currents require the ADC driver op-amp to settle within the acquisition window - use unity-gain buffers with at least 5 MHz bandwidth. Estimated: at 250 ksps, the acquisition phase is roughly 1 µs long; an op-amp with 10 V/µs slew rate settles in <200 ns.
The LTC2391HLX-16's parallel data bus (D0-D15) produces fast-edge transitions that can couple into analog inputs. Series-terminate each parallel output with 33 Ω resistors placed near the ADC, and add a ground-guard trace between the parallel bus and the analog input traces. When using the SPI-compatible serial mode, route SCK and SDO away from AIN+/AIN- and use the slowest acceptable SCK frequency to reduce ground bounce. Verify timing margins at the receiver's setup/hold specifications rather than relying on the ADC's nominal values.
Información de cumplimiento
RoHS compliant per the #PBF ordering suffix documented in the Analog Devices product family. Not AEC-Q100 qualified; for AEC-Q100 systems select from ADI's automotive-grade ADC families separately. H temperature grade supports -40C to +125C operation but does not imply automotive qualification.
