TSM1285BESA+T - 12-Bit 300ksps SAR ADC w/ Int Ref | Silicon Labs
Référence : TSM1285BESA+T ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $3.95 | $3,95 |
| 10 | $3.55 | $35,50 |
| 100 | $3.05 | $305,00 |
| 500 | $2.65 | $1 325,00 |
| 1 000 | $2.3 | $2 300,00 |
| 3 000 | $1.95 | $5 850,00 |
TSM1285BESA+T Présentation
An SAR (Successive Approximation Register) ADC is a type of analog-to-digital converter that uses a binary-search algorithm against an internal or external reference to digitize an input voltage in N clock cycles, producing one sample per conversion with deterministic latency. ADCs sit within the broader data-acquisition signal chain (sensor -> front-end amplifier -> ADC -> microcontroller/DSP) and serve as the bridge between the analog physical world and digital signal processing. Low-power, single-supply 12-bit SAR ADCs like the TSM1285 are widely deployed in industrial sensors, instrumentation, and embedded monitoring.
Key features include 12-bit resolution with no missing codes, a 300 ksps maximum sampling rate, an internal 2.5 V reference, a single-ended analog input, and an SPI-compatible serial output. The device delivers typical INL of +/-1 LSB and operates from -40C to +85C, making it suitable for industrial temperature environments. Low power consumption (~1 mA at 300 ksps) and a power-down mode that reduces current to nanoamp levels enable battery-powered and energy-harvesting applications.
Architecturally, the TSM1285 uses a charge-redistribution SAR core with an integrated track-and-hold, a precision bandgap reference, and a serial output shift register. The internal reference is trimmed during manufacture, eliminating external trim components. The serial interface supports SPI, QSPI, and MICROWIRE modes, allowing direct connection to most microcontrollers without glue logic. Conversion is initiated via a chip-select falling edge and the result is clocked out on subsequent SCLK rising edges.
Typical applications include industrial process control loop monitoring, portable battery-powered instrumentation, data-acquisition front-ends for sensor signals (temperature, pressure, strain), and embedded control systems. The internal reference simplifies designs that previously required an external reference plus a buffer amplifier.
When designing with this part, place a 1 nF to 10 nF ceramic bypass capacitor as close as possible to the VDD pin and a 10 uF bulk capacitor at the supply input. Maintain a quiet analog ground return path; do not share the analog ground return with noisy digital currents. The reference decoupling capacitor (typically 4.7 uF on REF) is critical for AC performance.
This page synthesizes distributor pricing, drop-in alternatives (same-brand MAX1285 family first, then cross-brand equivalents), and practical design notes not consolidated in the manufacturer datasheet.
Alternatives de remplacement direct pour TSM1285BESA+T — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Variantes de cette série
Modèles de la même série directement compatibles avec TSM1285BESA+T (même facteur de forme et même empreinte) — différant par Package, Input Type, Internal Reference, Architecture, RoHS Status.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
MAX1285BESA
✅ Remplacement direct✓ En stock
$7.97 / unité
Voir la fiche technique →MAX1285BCSA
✅ Remplacement direct✓ En stock
$5.4 / unité
Voir la fiche technique →MAX1284BCSA
✅ Remplacement direct✓ En stock
$9.95 / unité
Voir la fiche technique →MAX1284ACSA+T
✅ Remplacement direct✓ En stock
$6.45 / unité
Voir la fiche technique →TSM1285BCSA+
✅ Remplacement direct✓ En stock
$4.1 / unité
Voir la fiche technique →TSM1285BESA+
✅ Remplacement direct✓ En stock
$3.78 / unité
Voir la fiche technique →TSM1285BESA+T Valeurs maximales et caractéristiques électriques
| Résolution | 12 bits |
| Number of Channels | 1 input |
| Conversion Type | SAR (Successive Approximation) |
| Fréquence d'échantillonnage | 300 ksps |
| Input Configuration | Single-ended |
| Interface | SPI/QSPI/MICROWIRE-compatible serial |
| Analog Supply Voltage | 2.7 V to 3.6 V |
| Digital Supply Voltage | 2.7 V to 3.6 V |
| Internal Reference | 2.5 V (integrated) |
| Supply Current (typ. at 300 ksps) | ~1 mA |
| INL (typ.) | +/-1 LSB |
| Plage de température de fonctionnement | -40C to +85C |
| Boîtier | 8-pin SOIC (SO, 0.154" / 3.90 mm width) |
| Type de montage | Surface Mount |
| Statut RoHS | Compliant |
| Plage de tension d'entrée | 0 V to VREF (unipolar, single-ended) |
Configuration des broches de TSM1285BESA+T
| Broche 1 | VDD — Power supply input (2.7 V to 3.6 V) |
| Broche 2 | AIN — Analog input (single-ended, 0 V to VREF) |
| Broche 3 | |
| Broche 4 | REF — Reference voltage bypass / internal 2.5 V reference output |
| Broche 5 | SHDN — Shutdown input (active low) |
| Broche 6 | CS — Chip select (active low, initiates conversion on falling edge) |
| Broche 7 | DOUT — Serial data output (SPI) |
| Broche 8 | SCLK — Serial clock input |
Applications typiques
TSM1285BESA+T convient pour 8 applications: Industrial Process Control Sensors, Portable Battery-Powered Instrumentation, Data Acquisition Front-Ends, Embedded System Sensor Reading, Loop-Powered Transmitter Design, Medical Patient Monitoring Accessories, Automotive Sensor Conditioning Modules, HMI Touch and Proximity Interfaces.
Industrial Process Control Sensors
The TSM1285BESA+T's 12-bit resolution and 300 ksps sampling rate suit industrial sensors measuring pressure, temperature, flow, or strain in 4-20 mA or 0-10 V loops. The integrated 2.5 V reference eliminates external reference drift errors that would otherwise corrupt long-term calibration, and the single 2.7-3.6 V supply simplifies PLC-style front-ends. Place a 10 nF bypass capacitor directly at VDD; route the analog ground return away from switching noise for best INL performance in noisy industrial cabinets.
Recommandé
Portable Battery-Powered Instrumentation
At approximately 1 mA supply current during 300 ksps conversions and nanoamp-level standby, the TSM1285BESA+T supports battery-powered handheld instruments such as digital multimeters and field calibrators. The internal 2.5 V reference means no extra quiescent current from a separate reference IC, extending run-time on Li-ion or 2xAA cells. Use a low-quiescent LDO (such as MCP1700) upstream and enable the ADC only when a reading is needed.
Recommandé
Data Acquisition Front-Ends
The TSM1285BESA+T functions as a compact 12-bit ADC front-end in data-acquisition modules digitizing signals from thermocouples, RTDs, or load cells. Its SAR architecture provides deterministic conversion latency - critical when correlating samples to system events. With +/-1 LSB typical INL and an internal 2.5 V reference trimmed at the factory, the device eliminates the need for periodic calibration that external-reference designs often require. A small op-amp buffer (such as MCP6002) between the sensor and AIN improves drive accuracy at high sampling rates.
Recommandé
Embedded System Sensor Reading
Embedded microcontrollers read sensors via the TSM1285BESA+T's SPI interface with no glue logic. CS-driven conversions and MSB-first serial output work directly with most MCU SPI peripherals, including Silicon Labs EFM32, STM32, and Microchip PIC devices. The 300 ksps ceiling exceeds typical embedded sensor sampling needs (usually 1-10 ksps), giving designers headroom for oversampling and digital averaging to improve effective resolution beyond the raw 12 bits.
Recommandé
Loop-Powered Transmitter Design
In 4-20 mA smart transmitters, the TSM1285BESA+T digitizes the sensor signal and feeds result data to a microcontroller that drives the loop. Operating from a 3 V derived rail and drawing ~1 mA during conversion keeps total loop current draw within budget. The internal reference eliminates the voltage drop and extra current of an external reference shunt, simplifying the 4-20 mA compliance budget. Use a low-dropout regulator between the loop voltage and VDD for cold-start transient protection.
Recommandé
Medical Patient Monitoring Accessories
In medical accessory designs - not life-critical - the TSM1285BESA+T digitises signals from temperature probes, respiration sensors, or weight scales with adequate precision. The integrated reference reduces long-term drift, important for devices that must hold calibration across multi-year service intervals. Pair the ADC with an isolation barrier (such as ADuM1411) to meet IEC 60601 patient-leakage requirements when the accessory connects to a patient-connected host system.
Recommandé
Automotive Sensor Conditioning Modules
While not AEC-Q100 qualified, the TSM1285BESA+T is used in non-safety automotive cabin and body modules reading thermistor, position, or pressure sensors at module temperatures up to 85C. Designers typically add external TVS diodes (such as SMAJ5.0CA) on AIN and supply lines to survive load-dump transients. For under-hood or safety-critical applications, choose an AEC-Q100 qualified ADC such as MAX11100 or ADS1115-Q1 instead.
Recommandé
HMI Touch and Proximity Interfaces
In human-machine interfaces, the TSM1285BESA+T reads analog signals from capacitive or resistive touch pads and proximity sensors through their analog front-end. The 300 ksps rate supports oversampling strategies that improve noise immunity for reliable touch detection in industrial environments. The internal reference removes a precision analog rail, simplifying power-tree design and freeing PCB area for the MCU and HMI connectors.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour TSM1285BESA+T — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | MAX1285BESA | MAX1285BCSA | MAX1284BCSA | TSM1285BCSA+ |
|---|---|---|---|---|---|
| Brand | Silicon Labs (Touchstone) | Analog Devices (Maxim) | Analog Devices (Maxim) | Analog Devices (Maxim) | Silicon Labs (Touchstone) |
| Package | 8-SOIC (0.154") | 8-SOIC (0.154") - same | 8-SOIC (0.150") - narrower body | 8-SOIC (0.150") - narrower body | 8-SOIC (0.150") - narrower body |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Supply Voltage | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 2.7 V to 3.6 V |
| Internal Reference | 2.5 V (integrated) | 2.5 V (integrated) | 2.5 V (integrated) | 2.5 V (integrated) | 2.5 V (integrated) |
| Interface | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE |
| Number of Channels | 1 single-ended | 1 single-ended | 1 single-ended | 1 single-ended | 1 single-ended |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
Principaux différenciateurs
- Single 2.7-3.6 V supply with integrated 2.5 V reference (vs MAX1285BESA)
- Internal 2.5 V reference eliminates external reference drift errors (vs External-reference 12-bit ADC designs)
- 300 ksps SAR throughput in compact 8-pin SOIC (vs Multi-channel 12-bit ADCs in larger packages)
- SPI/QSPI/MICROWIRE-compatible serial interface (vs Parallel-output 12-bit ADCs)
Notes de conception
Place a low-ESR 0.1 uF ceramic bypass capacitor within 3 mm of the VDD pin (pin 1) and a 10 uF tantalum or ceramic bulk capacitor at the regulator output. Add a 4.7 uF X7R or X5R ceramic on REF (pin 4) for AC noise filtering of the internal 2.5 V reference. Keep digital and analog ground returns separated and joined at a single star point under the IC.
Use a solid analog ground plane on the layer directly beneath the IC. Keep the AIN trace short and surrounded by analog ground to minimise digital-noise coupling, and route SPI traces (CS, SCLK, DOUT) away from the analog input. Avoid running switching converter traces across the ADC's analog ground region.
Do not leave the SHDN pin floating - tie it to VDD through a 10 kohm pull-up or drive it directly from the MCU, since a floating SHDN can put the part into an undefined state that increases supply current or causes spurious conversions. Ensure CS returns high between conversions to start a new acquisition and avoid issuing additional SCLK pulses when CS is low, which would shift extra clocks into the serial stream.
Drive AIN through a low-output-impedance buffer (such as MCP6002 or AD8628) if the source impedance exceeds 1 kohm; higher source impedance degrades AC performance and INL at the 300 ksps maximum sampling rate. Add a small RC anti-aliasing filter (typ. 1 kohm + 1 nF) at AIN for wideband input sources to prevent aliasing of out-of-band noise into the conversion bandwidth.
Informations de conformité
RoHS and REACH compliant per Touchstone Semiconductor product information. Not AEC-Q100 qualified - choose MAX11100 or ADS1115-Q1 for automotive safety-critical applications.
