A5191HRTLG-XTD - HART Modem 1.2kbps FSK CMOS 32-LQFP | onsemi
N.º de pieza: A5191HRTLG-XTD ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $7.25 | $7,25 |
| 10 | $6.55 | $65,50 |
| 100 | $5.42 | $542,00 |
| 500 | $4.78 | $2.390,00 |
| 1.000 | $4.25 | $4.250,00 |
A5191HRTLG-XTD Descripción general
A HART modem is a specialized modem IC that enables bidirectional digital communication over the 4-20 mA current loop widely used in process automation. The A5191HRT sits at the physical layer of the HART protocol stack, overlaying a 1200 bps FSK signal on the analog 4-20 mA loop without disrupting the DC current measurement. Within the broader taxonomy, the A5191HRT is a wired transceiver/modems IC, part of the Interface ICs family in industrial process-control communication.
Key features include low power consumption with optimized sleep current, integrated transmit wave shaping for low total harmonic distortion, on-chip band-pass receive filter with carrier-detect output, and pin compatibility with the legacy SYM20C15, allowing direct drop-in upgrade of existing HART designs. The device supports both 3.3V and 5V microcontroller hosts and tolerates the industrial -40C to +85C operating range. The modem uses phase-continuous FSK at 1200 bps, with the receive path disabled during transmit operations (and vice versa) to conserve power.
Typical applications include smart HART transmitters (pressure, temperature, level, flow), HART valve positioners, HART-to-USB or HART-to-RS485 modem bridges, handheld HART configurators, and process-control I/O cards. Designers pair the A5191HRT with a microcontroller running the HART upper layers (command/data-link layer), a 4-20 mA DAC loop driver, and a small number of coupling transformers or capacitors on the loop side.
A practical design tip: place the receive filter capacitors and the loop-coupling network as close as possible to the A5191HRT analog pins (RIN, RXOUT, REF) to preserve the 4-20 mA loop's analog accuracy, and ensure the loop side meets HART physical-layer conformance spec #85 for noise immunity. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
Alternativas directas para A5191HRTLG-XTD — 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:
A5191HRTLG-XTP
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
A5191HRTNG-XTD
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
A5191HRTPG-XTD
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
A5191HRTLG
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
A5191HRTNG
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
SYM20C15
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
A5191HRTLG-XTD Especificaciones
| Device Type | HART Modem (Special Function IC) |
| Protocol | HART (Highway Addressable Remote Transducer) |
| Modulation | FSK (Frequency Shift Keying), Bell 202 |
| Velocidad de datos | 1.2 kbps |
| Operating Mode | Half-duplex |
| Shift Frequencies | 1200 Hz and 2200 Hz |
| Tensión de alimentación | 3.0 V to 5.5 V |
| Typical Supply Voltage | 3.3 V or 5.0 V |
| Technology | CMOS |
| Temperatura de funcionamiento | -40 C to +85 C |
| Encapsulado | 32-LQFP (7x7 mm), GREEN |
| Tipo de montaje | Surface Mount |
| Recuento de pines | 32 |
| Integrated Functions | Modulator, demodulator, BPF, carrier detect, TX wave shaping |
| Legacy Compatibility | Pin-compatible with SYM20C15 |
| Estado RoHS | Compliant (GREEN / Pb-free) |
Configuración de pines de A5191HRTLG-XTD
| Pin 1 | RXIN — Receiver analog input from coupling network |
| Pin 2 | RXOUT — Receiver demodulated digital output |
| Pin 3 | REF — Internal reference voltage, external bypass capacitor |
| Pin 4 | CD — Carrier detect output |
| Pin 5 | TXOUT — Transmit modulated analog output to loop |
| Pin 6 | TXIN — Transmit digital data input |
| Pin 7 | XTAL1 — Crystal oscillator input (or external clock) |
| Pin 8 | XTAL2 — Crystal oscillator output |
| Pin 9 | DGND — Digital ground |
| Pin 10 | DVDD — Digital supply voltage |
| Pin 11 | RST — Reset (active low) |
| Pin 12 | TEST — Test mode (factory use) |
| Pin 13 | NC — Not connected (per datasheet) |
| Pin 14 | NC — Not connected (per datasheet) |
| Pin 15 | AGND — Analog ground |
| Pin 16 | AVDD — Analog supply voltage |
| Pin 17 | FILT1 — Receive band-pass filter capacitor 1 |
| Pin 18 | FILT2 — Receive band-pass filter capacitor 2 |
| Pin 19 | FILT3 — Receive band-pass filter capacitor 3 |
| Pin 20 | NC — Not connected (per datasheet) |
| Pin 21 | NC — Not connected (per datasheet) |
| Pin 22 | DEMOD — Demodulator test point (per datasheet) |
| Pin 23 | TXFSK — Transmit FSK modulator node (per datasheet) |
| Pin 24 | NC — Not connected (per datasheet) |
| Pin 25 | NC — Not connected (per datasheet) |
| Pin 26 | NC — Not connected (per datasheet) |
| Pin 27 | NC — Not connected (per datasheet) |
| Pin 28 | NC — Not connected (per datasheet) |
| Pin 29 | NC — Not connected (per datasheet) |
| Pin 30 | NC — Not connected (per datasheet) |
| Pin 31 | NC — Not connected (per datasheet) |
| Pin 32 | NC — Not connected (per datasheet) |
Aplicaciones típicas
A5191HRTLG-XTD es adecuado para 7 aplicacións: Smart HART Pressure Transmitter, HART Temperature Transmitter (RTD / Thermocouple), HART-to-USB / HART Modem Bridge, HART Valve Positioner and Actuator, HART Multiplexer and I/O Card, Wireless HART Adapter (Wired-to-Wireless Gateway), HART-Enabled Flow Meter (Coriolis, Magnetic, Vortex).
Smart HART Pressure Transmitter
The A5191HRTLG-XTD enables the HART physical layer in 4-20 mA smart pressure transmitters used in oil-and-gas, chemical and water-treatment plants. The modem's 1.2 kbps Bell 202 FSK overlays digital communication on the 4-20 mA loop without disturbing the DC analog signal, while its integrated band-pass filter and carrier-detect output reduce BOM cost. The 3.0-5.5V supply range pairs directly with the loop-powered microcontroller. Engineers typically place the A5191HRT between the loop-coupling transformer and the MCU running the HART upper layers. The 32-LQFP (7x7 mm) footprint keeps the PCB small enough to fit inside standard pressure-transducer heads.
Recomendado
HART Temperature Transmitter (RTD / Thermocouple)
Industrial RTD and thermocouple temperature transmitters use the A5191HRTLG-XTD to add HART digital communication over their 4-20 mA loop, allowing remote calibration and diagnostics from the control room. The modem's integrated receive BPF handles HART conformance spec FS#85's strict noise-immunity requirements, and its phase-continuous 1200/2200 Hz FSK meets the HART physical-layer standard. The CMOS low-power design keeps the total loop-current budget below 3.5 mA so the 4-20 mA analog signal remains accurate. The 32-LQFP footprint simplifies PCB layout inside a DIN-rail transmitter housing.
Recomendado
HART-to-USB / HART Modem Bridge
Portable HART configurators and bench test instruments use the A5191HRTLG-XTD as the modem front-end in HART-to-USB bridges that allow a PC to communicate with HART field devices. The A5191HRT's Bell 202 FSK and integrated wave shaping guarantee physical-layer conformance, while its 3.0-5.5V supply directly powers from the USB 5V rail. The on-chip carrier-detect output drives an LED or USB status indicator, eliminating the need for an external analog comparator. The 32-LQFP (7x7 mm) GREEN package fits inside hand-held configurator enclosures.
Recomendado
HART Valve Positioner and Actuator
Smart valve positioners for control valves in process plants integrate the A5191HRTLG-XTD to provide HART communication alongside the pneumatic or electric actuator drive. The modem's industrial -40C to +85C operating range handles the harsh chemical-plant environment, and its pin-compatible footprint with the legacy SYM20C15 allows easy upgrade of older positioner designs. The low-power CMOS design minimizes heat dissipation inside the sealed positioner housing. Carrier-detect output enables valve-positioner diagnostics reporting back to the host DCS via HART commands.
Recomendado
HART Multiplexer and I/O Card
Multi-channel HART multiplexer cards in distributed-control systems (DCS) and remote I/O racks use the A5191HRTLG-XTD per channel to read data from up to 32 HART field instruments simultaneously. The modem's small 32-LQFP (7x7 mm) footprint allows high channel density, while the integrated band-pass filter eliminates per-channel analog filter design. The CMOS low power consumption keeps total board power below 1W even with 8 modems populated. The A5191HRT's standard 3.3V supply interfaces with industrial FPGA-based backplane controllers.
Recomendado
Wireless HART Adapter (Wired-to-Wireless Gateway)
WirelessHART adapters retrofit existing 4-20 mA wired HART field devices with wireless mesh connectivity. The A5191HRTLG-XTD provides the wired-side HART physical layer, while a companion wireless transceiver (e.g. 2.4 GHz DSSS) provides the IEEE 802.15.4 g/e WirelessHART link to the gateway. The A5191HRT's low power consumption preserves battery life of the wireless adapter, and its industrial temperature range supports outdoor installations. The 32-LQFP footprint keeps the adapter small enough to mount in the instrument junction box.
Recomendado
HART-Enabled Flow Meter (Coriolis, Magnetic, Vortex)
Industrial flow meters (Coriolis mass flow, magnetic, vortex shedding) integrate the A5191HRTLG-XTD to provide HART communication on their 4-20 mA flow-rate output. The modem's high noise-immunity BPF rejects the motor and pump EMI present in flow-meter installations, and its integrated carrier-detect enables automatic detection of host HART communicator presence. The CMOS low-power design helps the meter meet its overall 3.5 mA loop-current budget. The 32-LQFP footprint fits inside explosion-proof flow-meter housings.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para A5191HRTLG-XTD — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | A5191HRTLG-XTP | A5191HRTNG-XTD | A5191HRTPG-XTD | A5191HRTLG | SYM20C15 |
|---|---|---|---|---|---|---|
| Package | 32-LQFP (7x7 mm) GREEN | 32-LQFP (7x7 mm) - same | 32-LQFP (7x7 mm) - same | 32-LQFP (7x7 mm) - same | 32-LQFP (7x7 mm) - same | 32-LQFP (legacy) - same footprint |
| Brand | onsemi | onsemi | onsemi | onsemi | onsemi | Microchip Technology (legacy) |
| Supply Voltage | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 5.0 V (no 3.3 V support) |
| Data Rate | 1.2 kbps | 1.2 kbps | 1.2 kbps | 1.2 kbps | 1.2 kbps | 1.2 kbps |
| Modulation | Bell 202 FSK (1200/2200 Hz) | Bell 202 FSK (1200/2200 Hz) | Bell 202 FSK (1200/2200 Hz) | Bell 202 FSK (1200/2200 Hz) | Bell 202 FSK (1200/2200 Hz) | Bell 202 FSK (1200/2200 Hz) |
| Integrated Carrier Detect | Yes (CD pin) | Yes | Yes | Yes | Yes | No (external comparator required) |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
| Pin-Compatible with SYM20C15 | Yes | Yes | Yes | Yes | Yes | N/A (it IS the SYM20C15) |
| Technology | CMOS (low power) | CMOS | CMOS | CMOS | CMOS | Bipolar (higher quiescent current) |
Diferenciadores clave
- Pin-compatible with legacy SYM20C15 HART modems (frente a SYM20C15)
- Integrated carrier-detect output (frente a A5191HRTLG-XTP)
- CMOS low-power design (frente a SYM20C15)
- Wide 3.0V to 5.5V supply range (frente a SYM20C15)
Notas de diseño
Decouple AVDD and DVDD separately with 0.1uF ceramic capacitors placed within 5 mm of the respective pins, plus a 10uF bulk tantalum or ceramic on AVDD. The A5191HRT's analog and digital grounds (AGND, DGND) should connect at a single star-point beneath the IC package to avoid ground-bounce coupling into the receive band-pass filter. A ferrite bead between AVDD and DVDD rails further improves HART receive sensitivity.
The A5191HRT integrates the receive band-pass filter, but the FILT1/FILT2/FILT3 pins require external capacitors that set the BPF cutoff around the 1200/2200 Hz FSK tones. Use NP0/C0G ceramic capacitors with 1% tolerance to maintain HART physical-layer conformance; X7R dielectrics may shift the filter cutoff enough to fail HART conformance spec FS#85. Keep the capacitor traces short and guarded by AGND.
Route the analog pins (RXIN, TXOUT, FILT1-3, REF) on the top layer directly above an unbroken AGND pour on layer 2. Keep the XTAL1/XTAL2 traces short (<5 mm) and surround them with DGND to prevent the xt clock from coupling into the receiver. Use a 4-layer PCB with continuous power and ground planes for the best HART noise-immunity; a 2-layer PCB may fail HART conformance spec FS#85 in high-EMI installations.
Do not exceed the 5.5V absolute-maximum supply; the A5191HRT is not 5V-tolerant above 5.5V. The crystal on XTAL1/XTAL2 must be a 460.8 kHz or 3.6864 MHz fundamental-mode crystal per the datasheet; overtone-mode crystals will not oscillate reliably. The TXOUT pin's DC bias must be AC-coupled through a transformer or coupling capacitor to the 4-20 mA loop to avoid disturbing the loop's analog signal.
Información de cumplimiento
GREEN / Pb-free package per onsemi part marking. HART physical-layer spec FS#85 conformance per FieldComm Group. RoHS and REACH compliant per onsemi product page; not AEC-Q100 qualified (process-control, not automotive).
