My Inquiry
My Account
Texas Instruments TMS3705GDRQ1
- Part No.:
- TMS3705GDRQ1
- Manufacturer:
- Texas Instruments
- Category:
- RFID, RF Access, Monitoring ICs
- Package:
- 16-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
TMS3705GDRQ1.pdf
- Description:
- LF READER IC
- Quantity:
- Payment:
- Shipping:
Inventory:2,165
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
TMS3705GDRQ1 from Texas Instruments is a transponder base station IC for TI-RFid™ systems, driving antenna coils in automotive immobilization and access control applications. It delivers 134.2 kHz FSK-modulated carrier signals, detects and demodulates transponder responses, integrates a 16 MHz PLL clock generator, and operates from 4.5–5.5 V with sleep current as low as 0.2 mA.
For engineers reviewing the TMS3705GDRQ1 datasheet, TMS3705GDRQ1 pinout, TMS3705GDRQ1 application, or TMS3705GDRQ1 equivalent, this page provides verified functional context, validated pin roles, confirmed AES transponder compatibility, and precise electrical specifications required for automotive RF identification system design and qualification.
Technical Context
The TMS3705GDRQ1 implements an integrated full-bridge driver with independent short-circuit protection on ANT1/ANT2, a high-gain RF amplifier (GBW ≥ 2 MHz, phase shift ≤ 16° at 134 kHz), and a digital FSK demodulator that distinguishes high/low bits by frequency shift-not absolute values-using a programmable threshold with ±0.55 kHz hysteresis.
Its on-chip PLL generates a stable 16 MHz internal clock from a 4 MHz external oscillator input (via OSC1/OSC2) or microcontroller clock signal; F_SEL selects ×4 (high) or ×8 (low) multiplication. The device supports synchronous and asynchronous SCI communication with the host MCU and performs real-time transponder resonance-frequency measurement during prebit reception to auto-tune the carrier frequency divider (division factor 114–124).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Data rate | Up to 8 kbps - supports fast read/write cycles for AES transponders like TRPWS21GTEA and RF430F5xxx. |
| Carrier frequency | 134.2 kHz nominal - matches TI-RFid transponder resonance; adjustable via programmable frequency divider (114–124). |
| Supply voltage | 4.5–5.5 V - dual-rail operation: VDDA/VSSA for bridge drivers, VDD/VSS for logic blocks. |
| Sleep current | 0.015–0.2 mA - enables low-power standby in vehicle keyless entry systems with automatic wake-on-TXCT. |
| PLL output | 15.984–16.0166 MHz - jitter ≤6%; supplies internal timing for demodulation, SCI, and bridge control logic. |
| Antenna drive | Full-bridge output (ANT1/ANT2); ΣRDS(on) = 7–14 Ω - delivers sufficient current for 100–1000 µH antenna coils. |
| Demodulation method | FSK detection with adaptive threshold - uses measured low-bit frequency to set high/low decision boundary, enabling robust operation across transponder tolerances. |
Pinout & Package
16-pin SOIC (D) package, 9.9 mm × 3.91 mm body size, surface-mount compatible with standard automotive PCB assembly processes.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 SENSE | Analog input | RF amplifier input; DC-coupled to antenna coil; used for diagnosis and signal amplification. |
| 2 SFB | Analog output | RF amplifier output; feeds band-pass filter and limiter stage for analog-to-digital conversion of FSK response. |
| 3 D_TST | Digital output | Test output for digital signals; also serves as PLL output monitor in test mode. |
| 4 A_TST | Analog output | Test output for analog signals; used for debugging RF amplifier and limiter stages. |
| 5 ANT1 / 7 ANT2 | Driver outputs | Full-bridge antenna terminals; deliver complementary 134.2 kHz carrier; each protected against short-to-ground. |
| 6 VSSA / 8 VDDA | Power rails | Ground and supply for analog power blocks (bridge drivers, RF amplifier); isolated from digital supply to reduce noise coupling. |
| 9 VDD / 12 VSS/VSSB | Power rails | Digital supply (VDD) and ground (VSS/VSSB) for logic, PLL, SCI, and control logic; VSSB shared with PLL ground. |
| 10 OSC2 / 11 OSC1 | Oscillator interface | Crystal/resonator connection points; accepts 4 MHz external source or digital clock from MCU for PLL reference. |
| 14 SCIO | Digital output | SCI serial data output to MCU; transmits diagnostic bytes, transponder ID, and status flags in NRZ format. |
| 15 F_SEL | Digital input | PLL multiplication control: high = ×4 (16 MHz), low = ×8 (32 MHz); default high for TMS3705GDRQ1/AES use case. |
| 16 TXCT | Digital input | Transmit control input from MCU; falling edge initiates charge phase; rising edge triggers sleep after 100 ms. |
Key Features
| Feature | Design Value |
|---|---|
| AES transponder optimization | TMS3705GDRQ1 is explicitly recommended for use with AES transponders (e.g., TRPWS21GTEA, RF430F5xxx), unlike E/F variants intended for DST/MPT devices. |
| Integrated resonance measurement | Measures transponder low-bit frequency (134.2 kHz) during prebit reception and updates frequency divider register to maintain optimal carrier alignment. |
| Short-circuit protected full bridge | Independent overcurrent detection per ANT1/ANT2; shutdown <10 µs, auto-retry <10 ms - prevents supply collapse during antenna fault conditions. |
| Diagnostic byte generation | Performs real-time antenna health check during charge phase; reports failure via dedicated SCIO diagnostic byte to MCU without interrupting normal operation. |
| Low-power sleep mode | Draws only 0.2 mA total supply current in sleep; automatically entered 100 ms after TXCT goes high - ideal for battery-powered key fobs and passive entry systems. |
Applications
| Automotive Immobilization | Car Access Systems |
|---|---|
|
Use Scenario: Embedded in vehicle ECU to authenticate encrypted transponder keys during ignition sequence. IC Role / Device Role / Timing Role: Base station controller generating 134.2 kHz HDX carrier, receiving FSK-coded challenge-response from AES transponder, and delivering decrypted ID via SCIO to MCU. Use Value: Enables secure, contactless authentication compliant with ISO 11784/11785 and TI-RFid AES protocols; leverages built-in resonance tuning for consistent read range across temperature and coil variance. |
Use Scenario: Integrated into door handle modules to detect proximity and unlock doors upon valid key approach. IC Role / Device Role / Timing Role: Antenna driver and FSK demodulator handling bidirectional communication with RF430F5xxx transponders during low-duty-cycle polling. Use Value: Supports ultra-low-power wake-on-field detection via TXCT-controlled sleep/wake cycling; achieves <100 ms latency from field presence to unlock command. |
| Building Access Control | Livestock Identification Readers |
|
Use Scenario: Deployed in wall-mounted access panels to verify employee badges using TI-RFid AES protocol. IC Role / Device Role / Timing Role: Transponder base station IC managing antenna excitation, FSK demodulation, and SCI handshaking with building management MCU. Use Value: Delivers reliable read performance up to 15 cm with standard 100–1000 µH antennas; built-in diagnosis ensures field-deployed reliability without manual calibration. |
Use Scenario: Used in handheld livestock readers to scan ear tags containing TRPWS21GTEA transponders in farm environments. IC Role / Device Role / Timing Role: Portable base station IC powering antenna coil, detecting FSK response, and transmitting decoded animal ID via SCIO to embedded ARM processor. Use Value: Maintains operation across wide ambient temperature (–40°C to +85°C); short-circuit protection prevents damage from accidental antenna coil shorts in rugged field use. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transponder base station applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TMS3705DDRQ1 | Same SOIC-16 package and pinout; identical electrical specs; predecessor to TMS3705GDRQ1 per TI documentation. | Also qualified for AES transponder use; however, TMS3705GDRQ1 replaces it per official TI notice and offers updated production traceability. | Select TMS3705GDRQ1 for new designs requiring latest revision, extended lifecycle support, and documented AES compatibility. |
| TMS3705FDRQ1 | SOIC-16 pin-compatible; optimized for DST40/DST80/MPT transponders; not recommended for AES devices per TI specification. | Delivers higher performance with legacy transponders (e.g., TMS37145TEAx), but incompatible with TRPWS21GTEA or RF430F5xxx due to different modulation and timing tuning. | Choose only when interfacing with non-AES transponders; avoid for AES-based systems where TMS3705GDRQ1 is mandated. |
Compared with TMS3705DDRQ1 and TMS3705FDRQ1, the TMS3705GDRQ1 provides guaranteed AES transponder compatibility, updated manufacturing revision, and direct replacement assurance for DDRQ1 - making it the sole recommended choice for new automotive and secure access designs requiring TI-RFid AES compliance.
Availability
TMS3705GDRQ1 is available at Aetrix Electronics and suitable for automotive immobilization, car access systems, and building access control requiring stable component supply, long-term automotive-grade availability, and TI-qualified RF identification performance.
Supply support for TMS3705GDRQ1 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
Texas Instruments is a global semiconductor company specializing in analog, embedded processing, and wireless connectivity solutions, with leadership in automotive, industrial, and communications markets.
The TMS3705 product line is designed specifically for TI-RFid™ transponder base station applications, delivering integrated antenna driving, FSK demodulation, and AES-compliant secure communication for automotive and access control systems.
FAQ
What is the primary function of the TMS3705GDRQ1 in a TI-RFid system?
The TMS3705GDRQ1 serves as the transponder base station IC, driving the antenna coil at 134.2 kHz, sending modulated data to the transponder, and detecting/demodulating its FSK-encoded response. It interfaces directly with a microcontroller via SCIO and TXCT, and is explicitly recommended for use with AES transponders such as TRPWS21GTEA and RF430F5xxx. Its integrated PLL, full-bridge driver, and digital demodulator eliminate need for external timing or signal conditioning components in certified automotive access systems.
Why is TMS3705GDRQ1 specifically recommended for AES transponders while other variants are not?
TMS3705GDRQ1 is designated by Texas Instruments for AES transponder compatibility due to firmware-level tuning, timing calibration, and modulation parameters aligned with TRPWS21GTEA and RF430F5xxx requirements. In contrast, TMS3705FDRQ1 and TMS3705EDRQ1 are optimized for DST40/DST80/MPT protocols and lack the necessary configuration for AES handshake sequences and encryption key exchange. The datasheet explicitly states that only TMS3705DDRQ1 and TMS3705GDRQ1 are recommended in combination with AES products - and TMS3705GDRQ1 supersedes DDRQ1.
How does the TMS3705GDRQ1 handle antenna resonance variation across temperature and manufacturing tolerance?
The TMS3705GDRQ1 performs real-time transponder resonance-frequency measurement during the prebit reception phase, calculating the average counter state of eight consecutive low-bit periods (134.2 kHz). This value dynamically updates the programmable frequency divider register (division factor 114–124) to maintain optimal carrier alignment. The process occurs autonomously within the IC and requires no MCU intervention, ensuring consistent read range and reliability across –40°C to +85°C and across production batches of antenna coils.
What are the power supply requirements and sleep behavior of the TMS3705GDRQ1?
The TMS3705GDRQ1 requires two separate 4.5–5.5 V supplies: VDDA/VSSA for the full-bridge driver and RF amplifier, and VDD/VSS for digital logic and PLL. In normal operation, total supply current is 8–20 mA; in Sleep state - entered automatically 100 ms after TXCT goes high - total current drops to 0.015–0.2 mA. The device wakes instantly upon TXCT going low, resuming full operation without reset or reinitialization delay.
Does the TMS3705GDRQ1 require an external crystal or can it use a microcontroller clock source?
Yes, the TMS3705GDRQ1 supports both configurations: it can operate with a 4 MHz ceramic resonator connected between OSC1 and OSC2, or accept a 4 MHz (or 2 MHz) digital clock signal from the host microcontroller applied to OSC1. Its internal PLL multiplies the input by ×4 (F_SEL = high) to generate the required 16 MHz internal clock. This flexibility eliminates the need for a second oscillator in MCU-integrated systems and simplifies board layout for automotive access modules.
TMS3705GDRQ1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 16-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- RFID Transponder
- Frequency:
- 134.2kHz
- Standards:
- -
- Interface:
- RS 232, USB
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-SOIC
TMS3705GDRQ1 FAQ
1.How can I place an order for TMS3705GDRQ1 through Aetrix?
Please submit a Request for Quotation (RFQ) for TMS3705GDRQ1 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 TMS3705GDRQ1 reliable?
The price and inventory of TMS3705GDRQ1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TMS3705GDRQ1 is usually 5 days.
3.What payment methods are accepted for TMS3705GDRQ1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TMS3705GDRQ1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TMS3705GDRQ1?
TMS3705GDRQ1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TMS3705GDRQ1 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 TMS3705GDRQ1?
For technical support, including TMS3705GDRQ1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TMS3705GDRQ1 requirements.
6.How does Aetrix verify that TMS3705GDRQ1 is sourced from the original manufacturer or authorized distributors?
All TMS3705GDRQ1 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 TMS3705GDRQ1 meets industry standards.
7.What is the process for return or replacement of TMS3705GDRQ1?
All TMS3705GDRQ1 units undergo pre-shipment inspection (PSI). If there is an issue with TMS3705GDRQ1, 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 TMS3705GDRQ1 part is unused and in its original packaging.
Return procedure for TMS3705GDRQ1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TMS3705GDRQ1 Tags
-
SL2S2602FTBX
NXP Semiconductors
-
ST25DV04K-IER6S3
STMicroelectronics
-
ST25DV04K-IER6C3
STMicroelectronics
-
LXMSJZNCMD-217
Murata Electronics
-
NT3H2111W0FTTJ
NXP Semiconductors
-
NT3H2111W0FHKH
NXP Semiconductors
-
M24LR04E-RMC6T/2
STMicroelectronics
-
ST25DV04KC-JF6D3
STMicroelectronics
-
ST25DV64KC-IE6S3
STMicroelectronics
-
ST25DV64K-IER6T3
STMicroelectronics
-
NT3H2211W0FTTJ
NXP Semiconductors
-
NT3H2211W0FHKH
NXP Semiconductors
Tech Hub
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…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
