NXP Semiconductors TDA8004AT/C1,112

Overview

TDA8004AT/C1,112 from NXP Semiconductors (formerly Philips) is a complete analog smart card interface IC supporting 3 V or 5 V asynchronous cards. It integrates step-up conversion for VCC generation, ISO/IEC 7816-compliant I/O buffering (C4/C7/C8), 26 MHz crystal oscillator, and thermal/short-circuit protection on all card contacts. It operates between −25 °C and +85 °C with ≤65 mA continuous VCC output current and is used in banking card readers.

For engineers reviewing the TDA8004AT/C1,112 datasheet, TDA8004AT/C1,112 pinout, TDA8004AT/C1,112 application, or TDA8004AT/C1,112 equivalent, this page delivers verified specifications including VCC regulation accuracy (±5 %), CLK frequency division (1×/2×/4×/8×), active pull-up timing (200 ns edge delay), ESD rating (>6 kV on card side), and SO28 package mapping - all confirmed from the official Philips Rev. 03 datasheet.

Technical Context

The TDA8004AT/C1,112 implements an integrated step-up converter (VDDP input 4.5–6.5 V) to generate regulated 3 V or 5 V VCC for smart cards, with overload detection at ~90 mA and ripple <350 mV_p-p (20 kHz–200 MHz). Its clock circuitry accepts up to 26 MHz crystal or external clock on XTAL1/XTAL2 and divides output to 0–20 MHz via CLKDIV1/CLKDIV2 control pins with synchronous transitions and 45–55 % duty factor (except f_XTAL mode).

Three protected bidirectional I/O lines (I/O, AUX1, AUX2) feature internal 10 kΩ pull-ups to VCC, active pull-up capability delivering >1 mA to 0.9VCC on 80 pF loads, and master/slave arbitration with 200 ns edge delay. Fault detection includes card removal, VDD dropout, short-circuit, and thermal shutdown at 135 °C, triggering automatic deactivation sequences lasting 60–100 µs.

Key Specifications

Pinout & Package

Package: SO28 (SOT136-1), 7.5 mm body width, 28-lead plastic small outline package per Table 2 of Philips Rev. 03 datasheet.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar smart card interface applications.

Compared with SLB9670 and ST8024, the TDA8004AT/C1,112 uniquely combines integrated 5 V/3 V step-up conversion, 26 MHz oscillator, and ISO 7816-compliant I/O buffering in a single SO28 package - enabling drop-in implementation of banking-grade card readers without external power or clock components.

Availability

TDA8004AT/C1,112 is available at Aetrix Electronics and suitable for banking card readers, EMV payment terminals, and secure ID authentication systems requiring stable component supply across industrial temperature ranges and long lifecycle support.

Supply support for TDA8004AT/C1,112 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

NXP Semiconductors, headquartered in Eindhoven, Netherlands, is a global leader in secure connectivity solutions for automotive, industrial, and IoT applications, with legacy expertise in smart card technology from its Philips Semiconductor heritage.

The TDA8004AT/C1,112 belongs to NXP's legacy smart card interface product line, designed specifically to simplify ISO/IEC 7816-3 compliant reader development by integrating power, clock, protection, and signal conditioning functions into one SO28 IC.

FAQ

What is the maximum clock frequency supported by the TDA8004AT/C1,112 for smart card communication?

The TDA8004AT/C1,112 supports a maximum card clock frequency of 20 MHz, derived from its internal 26 MHz oscillator or external crystal via synchronous division by 1, 2, 4, or 8. This meets ISO/IEC 7816-3 and EMV requirements for high-speed ATR and data transfer. The TDA8004AT/C1,112 guarantees 45–55 % duty cycle for divided frequencies and maintains jitter below 100 ps with proper layout per AN97036.

How does the TDA8004AT/C1,112 handle dual-voltage smart cards (3 V and 5 V)?

The TDA8004AT/C1,112 selects output voltage via the 5V/3V pin: HIGH configures VCC for 5 V ±5 %, LOW for 3 V ±5 %. It delivers up to 65 mA continuously in either mode, with overload detection at ~90 mA and ripple <350 mV_p-p. The TDA8004AT/C1,112 uses separate decoupling (2 × 100 nF or 100 nF + 220 nF MLCC) tied to CGND to maintain regulation stability during transient loads.

What protection features does the TDA8004AT/C1,112 provide for smart card contacts?

The TDA8004AT/C1,112 provides thermal shutdown at 135 °C, short-circuit protection on VCC, and enhanced ESD tolerance (>6 kV HBM) on all card-contact pins (I/O, RST, VCC, AUX1, CLK, AUX2, PRES). It also detects card removal during transactions and initiates automatic deactivation. These protections are hardware-enforced and signaled via the open-drain OFF pin, which pulls LOW during faults.

Can the TDA8004AT/C1,112 operate without an external crystal?

Yes - the TDA8004AT/C1,112 includes a 26 MHz integrated crystal oscillator and can drive the card clock directly from it. Alternatively, an external clock source (2–26 MHz) may be applied to XTAL1 with XTAL2 left open. The TDA8004AT/C1,112 requires no external crystal when using the internal oscillator, reducing BOM count and board space in cost-sensitive designs.

What is the purpose of the dual PRES pins (pins 9 and 10) on the TDA8004AT/C1,112?

Pins 9 (PRES) and 10 (PRES) are complementary card presence inputs: PRES is active LOW, PRES is active HIGH. Either pin asserting its active state signals card presence to the TDA8004AT/C1,112, accommodating normally-open or normally-closed mechanical switches in card connectors. No internal debouncing is provided, so software must handle switch bounce, but first-edge detection ensures reliable take-off detection during active sessions.