My Inquiry
My Account
Allegro MicroSystems A1338LLETR-P-DD-T
- Part No.:
- A1338LLETR-P-DD-T
- Manufacturer:
- Allegro MicroSystems
- Category:
- Angle, Linear Position Measuring
- Package:
- 14-TSSOP (0.173", 4.40mm Width)
- Datasheet:
-
A1338LLETR-P-DD-T.pdf
- Description:
- ANGLE SENSOR IC W/ ADVANCED DIAG
- Quantity:
- Payment:
- Shipping:
Inventory:4,452
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
A1338LLETR-P-DD-T from Allegro MicroSystems is a dual-die, contactless 0° to 360° Hall-effect angle sensor IC with SPI interface and PWM output, delivering 12-bit resolution in Low RPM mode and 10-bit resolution in High RPM mode, configurable refresh rates from 25 µs to 3200 µs, and designed for automotive electronic power steering (EPS) and throttle position sensing.
For engineers reviewing the A1338LLETR-P-DD-T datasheet, A1338LLETR-P-DD-T pinout, A1338LLETR-P-DD-T application, or A1338LLETR-P-DD-T equivalent, key selection considerations include dual-die redundancy support, programmable EEPROM calibration, SENT/PWM protocol flexibility, and AEC-Q100-compliant operation across –40°C to +150°C ambient.
Technical Context
The A1338LLETR-P-DD-T integrates two independent SoC dies in a single 24-pin TSSOP package, each featuring Circular Vertical Hall (CVH) front-end sensing, on-chip temperature compensation, digital signal processing, and dedicated SPI/SENT/PWM output paths. Each die supports full diagnostics including logic built-in self-test (LBIST), 4-bit CRC on SPI messages, and user-programmable missing magnet error flags.
It operates in two configurable modes: Low RPM mode (up to 12-bit effective resolution, 200 µs refresh at AVG=011) and High RPM mode (10-bit resolution, 25 µs refresh, up to 7600 rpm sensing). Angle data is derived from magnetic field vector direction in the x-y plane, with latency-compensated output and EEPROM-stored calibration parameters including adjustable 0° reference point and CW/CCW rotation direction.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Angle Range | 0° to 360° absolute measurement - enables full-rotation position feedback without mechanical stops or multi-turn gearing. |
| Resolution | 12-bit in Low RPM mode, 10-bit in High RPM mode - determines smallest detectable angular change: ~0.087° (12-bit) or ~0.35° (10-bit). |
| Refresh Rate | Configurable 25 µs to 3200 µs via EEPROM - allows trade-off between latency and noise rejection for specific motor speed profiles. |
| Output Protocols | SPI (mode 3, 10 MHz max) and PWM - SPI enables high-speed register access and diagnostics; PWM provides analog-compatible duty-cycle output (5–95%) for legacy controllers. |
| Supply Voltage | 3.7 V to 16 V, absolute max 26.5 V - supports direct connection to automotive battery with reverse-battery protection down to –18 V. |
| Operating Temp | –40°C to +150°C ambient - qualified per AEC-Q100 Grade 0, suitable for under-hood EPS and transmission control modules. |
| Magnetic Sensing | Up to 7600 rpm at full accuracy, up to 30,000 rpm with reduced accuracy - enables use in high-speed throttle and PRNDL applications. |
Pinout & Package
Package: 24-pin TSSOP (Suffix LE), lead-free with 100% matte-tin plating, thermal resistance RθJA = 82°C/W.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| BYP1_1, BYP2_1 BYP1_2, BYP2_2 | External bypass capacitor terminals (die 1 & 2) | Stabilize internal regulators; BYP1_1/BYP1_2 require 0.1 µF to GNDD; BYP2 pins enable elevated SPI output voltage (3.1 V) when used. |
| CS_1/ID0_1, CS_2/ID0_2 | SPI chip select / SENT address bit (die 1 & 2) | Active-low SPI enable; also serves as ID0 for SSENT/ASENT addressing - enables independent communication with dual dies. |
| SCLK_1/ID1_1, SCLK_2/ID1_2 | SPI clock / SENT address bit (die 1 & 2) | Provides synchronous timing for SPI reads/writes; doubles as ID1 for SENT peripheral addressing in redundant configurations. |
| MISO_1, MISO_2 MOSI_1, MOSI_2 | SPI data I/O (die 1 & 2) | Full-duplex SPI interface per die - supports concurrent diagnostics and angle readout from both sensors without bus contention. |
| SENT_1/PWM_1 SENT_2/PWM_2 | Dual independent output channels | PWM output per die (5–95% duty cycle proportional to angle); supports functional safety via cross-checking of dual outputs. |
| VCC_1, VCC_2 GNDD_1, GNDD_2 GNDA_1 | Power and ground (die 1 & 2) | Independent power domains per die - isolates fault propagation; GNDA_1 is analog ground for CVH front-end; GNDD_x are digital grounds. |
| BIAS_1, BIAS_2 | Bias configuration terminal | Connect to GND or 3.3 V to configure internal bias current - sets CVH sensitivity and noise performance for target magnet strength. |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent SoC dies | Enables ASIL-D compliant redundancy: two physically separate sensing paths in one package eliminate single-point failure risk in EPS and brake-by-wire. |
| EEPROM with ECC | 100-cycle endurance with error correction ensures reliable storage of end-of-line calibration, 0° reference offset, rotation direction, and diagnostic masks across vehicle lifetime. |
| Programmable refresh rate | 25–3200 µs range allows optimization for specific application dynamics - e.g., 25 µs for high-speed throttle actuation, 200 µs for seatbelt motor positioning. |
| CVH technology | Air-gap-independent single-channel sensing eliminates need for precise magnet-to-sensor spacing - reduces assembly cost and improves robustness against mechanical tolerance stack-up. |
| On-chip LBIST & diagnostics | User-initiated logic BIST covers >70% of digital logic in ≤10 ms; combined with signal path diagnostics, meets ISO 26262 FMEDA requirements for safety mechanisms. |
Applications
| Electronic Power Steering (EPS) | Throttle Position Sensing |
|---|---|
Use Scenario: Real-time measurement of steering column rotation angle for assist torque calculation and lane-keeping feedback. IC Role / Device Role / Timing Role: Primary angle sensor providing 0°–360° absolute position to EPS ECU via PWM; dual-die architecture supports cross-validation with secondary sensor. Use Value: 12-bit resolution and <60 µs response time enable sub-degree control accuracy at low speeds; 7600 rpm capability supports fast steering transients without aliasing. | Use Scenario: Detection of accelerator pedal position and rate-of-change for engine management and emissions control. IC Role / Device Role / Timing Role: Redundant angle sensor delivering synchronized PWM outputs to main and backup ECUs; operates in High RPM mode for <25 µs update latency. Use Value: Dual-die independence prevents common-cause failure; programmable 0° reference allows precise alignment to mechanical stop positions during calibration. |
| Seatbelt Motor Position | Rotary PRNDL Selector |
Use Scenario: Monitoring spool rotation in pretensioner motors to determine belt tension and deployment readiness. IC Role / Device Role / Timing Role: Low-power angle sensor operating in Low RPM mode (200 µs refresh), interfaced via SPI for diagnostics and EEPROM configuration during vehicle assembly. Use Value: 12-bit resolution enables detection of <0.1° motor movement; EEPROM-stored calibration compensates for gear backlash and motor winding variance. | Use Scenario: Encoding rotary knob position for automatic transmission gear selection (Park, Reverse, Neutral, Drive, Low). IC Role / Device Role / Timing Role: Contactless 360° position sensor with SENT output for high-EMI environments; dual-die configuration supports fail-operational behavior during gear shift transitions. Use Value: CVH air-gap independence tolerates ±0.5 mm mechanical misalignment; SENT output provides deterministic timing and CRC-protected data for ASIL-B compliance. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar angle sensing applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AMS AS5055A | Single-die, 14-bit resolution, SPI-only output, no PWM/SENT; requires external EEPROM for calibration. | Lacks dual-die redundancy and automotive-grade diagnostics; not AEC-Q100 qualified. | Use where higher resolution is prioritized over functional safety and redundancy. |
| Infineon TLI4971-A020T4 | Current sensor with integrated angle measurement; 12-bit resolution, SENT output only; no SPI interface or EEPROM programming. | Designed for combined current + angle sensing in motor drives; lacks independent dual-die architecture. | Choose when simultaneous phase current and rotor position feedback are required in BLDC inverters. |
Compared with AMS AS5055A and Infineon TLI4971-A020T4, the A1338LLETR-P-DD-T uniquely delivers dual-die redundancy, EEPROM-based end-of-line calibration, and flexible SPI/PWM output - making it the only option qualified for ASIL-D–capable EPS systems requiring hardware-level fault containment.
Availability
A1338LLETR-P-DD-T is available at Aetrix Electronics and suitable for electronic power steering (EPS), throttle position sensing, and rotary PRNDL applications requiring stable component supply, long-term automotive lifecycle support, and AEC-Q100-compliant traceability.
Supply support for A1338LLETR-P-DD-T includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Allegro MicroSystems is a U.S.-based semiconductor company specializing in high-performance magnetic sensing and power ICs for automotive and industrial markets.
The A1338 product line delivers precision contactless angle sensing using Circular Vertical Hall (CVH) technology, engineered specifically for safety-critical automotive subsystems including EPS, transmission controls, and brake actuators.
FAQ
What is the primary function of the A1338LLETR-P-DD-T in automotive systems?
The A1338LLETR-P-DD-T functions as a dual-die, contactless 0° to 360° angle sensor IC that measures rotational position using Circular Vertical Hall (CVH) technology. It delivers high-resolution angular data via SPI and PWM outputs, enabling real-time feedback for electronic power steering, throttle control, and gear selector systems. Its dual-die architecture supports functional safety requirements by allowing cross-checking between independent sensing paths - a critical feature for ASIL-D–compliant applications. The A1338LLETR-P-DD-T is explicitly designed for automotive environments with AEC-Q100 qualification and –40°C to +150°C operation.
How does the dual-die configuration of the A1338LLETR-P-DD-T improve system reliability?
The A1338LLETR-P-DD-T integrates two electrically independent SoC dies in a single 24-pin TSSOP package, each with its own CVH sensor, signal chain, EEPROM, and output driver. This physical separation prevents common-cause failures - if one die experiences latch-up, ESD damage, or magnetic interference, the second die continues operation with full functionality. Both dies support identical SPI register maps and synchronized PWM outputs, enabling real-time comparison in the host ECU. This architecture directly supports ISO 26262 ASIL-D requirements for fault detection and mitigation in safety-critical applications like EPS. The A1338LLETR-P-DD-T's dual-die design is validated in production for automotive use, unlike software-based redundancy schemes.
Can the A1338LLETR-P-DD-T operate in both Low RPM and High RPM modes simultaneously?
No, the A1338LLETR-P-DD-T cannot operate both dies in different RPM modes simultaneously - the RPM mode (Low or High) is configured globally via EEPROM register bit RPM and applies identically to both dies. In Low RPM mode, each die performs internal averaging (configurable from 1× to 128× samples), yielding up to 12-bit effective resolution and refresh rates from 200 µs to 3200 µs. In High RPM mode, averaging is disabled, delivering 10-bit resolution at 25 µs minimum refresh rate for high-speed applications like throttle actuation. The A1338LLETR-P-DD-T's dual-die redundancy is maintained in both modes, but mode selection is unified across the device to ensure consistent timing and diagnostic behavior between channels.
What diagnostic capabilities does the A1338LLETR-P-DD-T provide for functional safety compliance?
The A1338LLETR-P-DD-T provides three layers of diagnostics: (1) On-chip logic built-in self-test (LBIST) covering >70% of digital logic in ≤10 ms, initiated via SPI or SENT; (2) Full signal path diagnostics verifying CVH front-end, ADC, digital processing, and output drivers; and (3) 4-bit CRC on all SPI transactions plus user-programmable missing magnet error flags. These features enable detection of stuck-at faults, timing violations, and magnetic field degradation - satisfying ISO 26262 ASIL-B requirements out-of-the-box and supporting ASIL-D architectures when combined with dual-die cross-checking. The A1338LLETR-P-DD-T's diagnostics are fully documented in its functional safety manual and validated per AEC-Q100.
Is the A1338LLETR-P-DD-T compatible with standard automotive PWM interfaces?
Yes, the A1338LLETR-P-DD-T PWM output is fully compatible with standard automotive PWM interfaces: duty cycle ranges linearly from 5% (0°) to 95% (360°), with reserved 0% and 100% states for error reporting. It supports three carrier frequencies (122 Hz, 1.024 kHz, 2.048 kHz) selectable via EEPROM, and maintains ±10% frequency tolerance and <0.1% duty cycle jitter at 2 kHz. Output drive capability is 30 mA sink current with defined high/low voltage levels (VPWM(H) ≥ 0.7 × VS, VPWM(L) ≤ 0.4 V) across 2 kΩ–50 kΩ pull-up resistors. The A1338LLETR-P-DD-T's PWM interface meets OEM specifications for throttle and steering position sensors and requires no external conditioning circuitry.
A1338LLETR-P-DD-T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Allegro MicroSystems
- Package/Case:
- 14-TSSOP (0.173", 4.40mm Width)
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Programmable:
- -
- For Measuring:
- Angle
- Technology:
- Hall Effect
- Rotation Angle - Electrical, Mechanical:
- 0° ~ 360°, Continuous
- Linear Range:
- -
- Output:
- PWM, SPI
- Output Signal:
- Programmable
- Actuator Type:
- External Magnet, Not Included
- Linearity:
- -
- Resistance:
- -
- Resistance Tolerance:
- -
- Voltage - Supply:
- 3.7V ~ 18V
- Mounting Type:
- Surface Mount
- Termination Style:
- Gull Wing
- Operating Temperature:
- -40°C ~ 150°C (TA)
- Grade:
- -
- Qualification:
- -
- Supplier Device Package:
- 14-TSSOP
A1338LLETR-P-DD-T FAQ
1.How can I place an order for A1338LLETR-P-DD-T through Aetrix?
Please submit a Request for Quotation (RFQ) for A1338LLETR-P-DD-T on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for A1338LLETR-P-DD-T reliable?
The price and inventory of A1338LLETR-P-DD-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for A1338LLETR-P-DD-T is usually 5 days.
3.What payment methods are accepted for A1338LLETR-P-DD-T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for A1338LLETR-P-DD-T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for A1338LLETR-P-DD-T?
A1338LLETR-P-DD-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your A1338LLETR-P-DD-T order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for A1338LLETR-P-DD-T?
For technical support, including A1338LLETR-P-DD-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your A1338LLETR-P-DD-T requirements.
6.How does Aetrix verify that A1338LLETR-P-DD-T is sourced from the original manufacturer or authorized distributors?
All A1338LLETR-P-DD-T products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that A1338LLETR-P-DD-T meets industry standards.
7.What is the process for return or replacement of A1338LLETR-P-DD-T?
All A1338LLETR-P-DD-T units undergo pre-shipment inspection (PSI). If there is an issue with A1338LLETR-P-DD-T, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The A1338LLETR-P-DD-T part is unused and in its original packaging.
Return procedure for A1338LLETR-P-DD-T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
A1338LLETR-P-DD-T Tags
-
TLV493DA1B6HTSA2
Infineon Technologies
-
EVW-AE4001B14
Panasonic Electronic Components
-
3382G-1-103G
Bourns Inc.
-
TLE5501E0001XUMA1
Infineon Technologies
-
HAL830UT-A
TDK-Micronas GmbH
-
TLE5009E1000FUMA1
Infineon Technologies
-
TLE5501E0002XUMA1
Infineon Technologies
-
HAL3725DJ-A
TDK-Micronas GmbH
-
HAL3727DJ-A
TDK-Micronas GmbH
-
HMC1501-TR
Honeywell Aerospace
-
HMC1512-TR
Honeywell Aerospace
-
AAS33001LLEATR-5
Allegro MicroSystems
Tech Hub
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
