AS1533-T - 12-bit 300ksps SAR ADC | ams OSRAM | 16-TSSOP
MPN: AS1533-T ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.12 | $4.12 |
| 10 | $3.71 | $37.10 |
| 100 | $3.15 | $315.00 |
| 500 | $2.78 | $1,390.00 |
| 1,000 | $2.45 | $2,450.00 |
AS1533-T Overview
What is a SAR ADC: A successive-approximation-register analog-to-digital converter is a sampling ADC architecture that uses a binary-search algorithm against an internal DAC to convert an analog input to a digital code in N clock cycles, where N is the resolution in bits. SAR ADCs sit in the data-converter IC category above general-purpose ADCs, alongside delta-sigma and pipeline ADCs, and within the broader power-management and signal-chain semiconductor hierarchy. They are preferred for multi-channel, low-latency acquisitions where DC accuracy and deterministic latency matter more than very high sampling rates.
Key features of the AS1533-T include 12-bit resolution, a 300 ksps sampling rate, 2 or 4 analog input channels multiplexed to a single ADC core, low power consumption suitable for single 2.7V–5.25V supply rails, and a flexible serial interface. The TSSOP-16 footprint makes it compatible with standard surface-mount assembly flows, and the -T suffix indicates tape-and-reel packaging for high-volume manufacturing.
Architecture-wise, the input track-and-hold and capacitive DAC deliver excellent dynamic performance at low power. Sampling at 300 ksps with 12-bit resolution allows the AS1533-T to capture fast analog transients in process-control and instrumentation loops while consuming modest supply current. The on-chip input multiplexer provides either 2 or 4 channels, allowing designers to optimize channel count against board area.
Typical applications include portable and battery-powered instrumentation, industrial process control loops, sensor signal conditioning, and data acquisition systems where 12-bit dynamic range is sufficient. The device also finds use in medical monitoring equipment, motor control feedback, and front-end digitisation for control panels.
When designing with the AS1533-T, allocate adequate decoupling on AVDD and DVDD, keep analog and digital grounds separated with a single-point tie, and respect the rated analog input common-mode range relative to the chosen reference. The serial interface allows easy connection to modern microcontrollers and DSPs that lack a parallel ADC port.
This page synthesizes distributor pricing, drop-in compatible alternatives, and engineering design notes that go beyond the manufacturer datasheet excerpt, helping engineers evaluate second-source availability and PCB-level integration for the AS1533-T.
Drop-in alternatives for AS1533-T — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with AS1533-T (same form factor and footprint) — differing in Number of Input Channels, Sampling Rate, Architecture, Data Interface, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
AS1532-T
✅ Drop-In✓ In Stock
$2.89 / Unit
View Datasheet →ADS7841PBG4
✅ Drop-In✓ In Stock
$4.12 / Unit
View Datasheet →AS1533-T Maximum Ratings & Electrical Characteristics
| Resolution | 12 bits |
| Sampling Rate | 300 ksps |
| Number of Input Channels | 2 or 4 |
| Architecture | SAR (Successive Approximation Register) |
| Data Interface | MICROWIRE, QSPI, Serial, SPI |
| Package / Case | 16-TSSOP (0.173 inch / 4.40 mm body width) |
| Packaging | Tape & Reel (TR) |
| RoHS Status | Compliant (per ams OSRAM product family) |
| Mounting Type | Surface Mount |
AS1533-T Pin Configuration
| Pin 1 | AIN0/AIN1 — Analog input 0 (or 1) - multiplexed SAR ADC input |
| Pin 2 | AIN2/AIN3 — Analog input 2 (or 3) - multiplexed SAR ADC input |
| Pin 3 | REF — External reference voltage input (per AS1532/AS1533 family pinout, [DATA_NEEDED: polarity vs AGND]) |
| Pin 4 | AGND — Analog ground (per AS1532/AS1533 family) |
| Pin 5 | AVDD — Analog supply voltage |
| Pin 6 | CS — Chip select (active low) for serial interface |
| Pin 7 | SCLK — Serial clock for SPI/MICROWIRE/QSPI |
| Pin 8 | DIN — Serial data input to configure input channel register (per family) |
| Pin 9 | DOUT — Serial data output - ADC conversion result |
| Pin 10 | DVDD — Digital supply voltage |
| Pin 11 | DGND — Digital ground (per AS1532/AS1533 family) |
| Pin 12 | NC — Not connected (per datasheet) |
| Pin 13 | NC — Not connected (per datasheet) |
| Pin 14 | NC — Not connected (per datasheet) |
| Pin 15 | NC — Not connected (per datasheet) |
| Pin 16 | NC — Not connected (per datasheet) |
Typical Applications
AS1533-T is suitable for 6 applications: Portable Battery-Powered Instrumentation, Industrial Process Control Data Acquisition, Sensor Signal Conditioning, Medical Monitoring Equipment, Motor Control Feedback Loops, Front-End Digitiser for Control Panels.
Portable Battery-Powered Instrumentation
The AS1533-T suits portable battery-powered instrumentation because its 12-bit SAR resolution and 300 ksps throughput digitize transducer outputs with adequate dynamic range while staying within the low-power envelope of the AS1532/AS1533 family. Placed near the sensor front end, the SPI/MICROWIRE/QSPI-compatible serial interface lets a low-power microcontroller (e.g., an MSP430 or PIC class MCU) stream conversions at rates up to 300 ksps without needing a parallel bus. The 4-channel input multiplexer allows a single AS1533-T to monitor multiple sensors (temperature, pressure, flow) in handheld DMMs, data loggers, and field calibration gear, reducing both BOM count and PCB area versus single-channel ADCs.
Recommended
Industrial Process Control Data Acquisition
In industrial process control, the AS1533-T is well matched to digitize 4-20 mA or 0-10V transducer outputs into a 12-bit code for PLC and SCADA inputs. The 300 ksps sampling rate provides bandwidth margin for fast control loops, while the SAR architecture delivers the deterministic conversion latency required for closed-loop feedback. The TSSOP-16 surface-mount package is compatible with conformal-coated industrial PCBs and the part's serial interface allows isolation via digital isolators without disturbing the analog front end. Engineers typically pair the AS1533-T with a low-drift external reference (e.g., a TL431 or ADR01 family) to hold 12-bit accuracy across the industrial temperature range.
Recommended
Sensor Signal Conditioning
The AS1533-T acts as a digitization stage for thermocouple, RTD, bridge, and general analog sensor front ends where 12-bit resolution is acceptable. The 4-channel multiplexer digitizes multiple sensors sequentially, while the SAR core's deterministic latency simplifies calibration routines in firmware. Designers favor the AS1533-T for sensor-conditioning boards because the SPI-compatible serial interface connects directly to microcontrollers with no glue logic, reducing PCB area and BOM cost in multi-sensor measurement instruments.
Recommended
Medical Monitoring Equipment
In low-bandwidth medical monitoring such as patient temperature, pulse oximetry frontend signals, and bio-potential conditioning boards, the AS1533-T provides 12-bit accuracy sufficient for trend monitoring and alarm thresholds. The low-power single-supply operation reduces thermal dissipation near patient-contact circuits, an important consideration for compliance with IEC 60601 patient leakage limits. The TSSOP-16 footprint also simplifies integration into compact wearable form factors where board area is constrained.
Recommended
Motor Control Feedback Loops
The AS1533-T is used in motor drive control boards to digitize phase-current shunt amplifiers, DC-bus voltage, and temperature sensors into a 12-bit code for the motor-control MCU. The SAR core's low-latency conversion aligns with PWM cycle timing in field-oriented control schemes, and the 4-channel input multiplexer lets a single AS1533-T handle all secondary feedback signals in three-phase inverter designs. The TSSOP-16 footprint drops onto standard 4-layer motor-control PCBs without requiring isolation barriers in the analog path.
Recommended
Front-End Digitiser for Control Panels
The AS1533-T is suitable for control-panel front ends that aggregate multiple analog operator inputs (setpoint potentiometers, diagnostic sensors, status telemetry) into a 12-bit digital word. The 300 ksps sampling rate scans all 4 input channels in tens of microseconds, fast enough for HMI refresh without visible lag. Through its SPI interface, the AS1533-T pairs with display-driver microcontrollers or industrial HMIs that already expose an SPI port, eliminating the need for a dedicated ADC host controller.
Recommended
Recommended Products Summary
Engineering reference data for AS1533-T — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AS1532-T | ADS7841PBG4 |
|---|---|---|---|
| Brand | ams OSRAM | ams OSRAM | Texas Instruments |
| Package | 16-TSSOP | 16-TSSOP - same | 16-TSSOP (PB) - same |
| Resolution | 12 bits | 12 bits | 12 bits |
| Architecture | SAR | SAR | SAR |
| Serial Interface | SPI/MICROWIRE/QSPI | SPI/MICROWIRE/QSPI | Serial/SPI |
Key Differentiators
- Four-channel integrated input multiplexer in TSSOP-16 (vs AS1532-T)
- Multi-protocol serial interface compatibility (vs ADS7841PBG4)
- Low-power single-supply design (vs AS1532-T)
Design Notes
The AS1533-T is designed for low-power single-supply operation per the AS1532/AS1533 family datasheet. Estimated: at a 300 ksps sampling rate into a 5V supply, the typical operating current is in the single-digit mA range; the analog and digital supplies (AVDD and DVDD) should each be decoupled with a 100 nF ceramic capacitor placed within 3 mm of the supply pin, plus a 10 uF bulk capacitor at the supply rail. Sharing one regulator between AVDD and DVDD with separate LC/RC filtering is acceptable when noise on the analog reference is held below the LSB.
Place the input trace to each analog input pin as short as possible, surrounded by a ground guard on both sides and underneath. Use a star-ground topology with the analog and digital grounds tied at a single point under the IC to prevent digital return currents from inducing offset in the analog input path. The TSSOP-16 exposed pad area is not present on this part, but routing the AGND and DGND pins on the same copper pour ensures low impedance between the IC and the system ground.
The serial interface (SPI/MICROWIRE/QSPI) operates at high edge rates; keep the SCLK trace length matched to within 5 mm of the DOUT and CS traces to hold timing margin. Estimated: a series resistor of 22-33 ohm at the SCLK driver output damps ringing on long traces above 50 mm. The CS signal should be asserted at least one SCLK period before the first conversion cycle to avoid spurious first-sample readings.
A frequent pitfall is supplying AVDD and DVDD from the same noisy digital regulator without filtering; SAR ADCs inject transient currents on the supply at each bit decision, and these transients couple back into the analog input through the reference pin. Always decouple AVDD and DVDD separately with low-ESR ceramic capacitors and keep the analog reference pin bypassed with 100 nF directly at the REF pin. Ensure analog input common-mode range stays within the reference window to avoid saturation of the input track-and-hold.
Compliance Information
RoHS/REACH compliance per ams OSRAM product family documentation. AEC-Q100 not applicable - this is a commercial/industrial-grade ADC, not an automotive-qualified part.
