73S8014BN

The 73S8014BN is a single smart card (ICC) interface circuit designed to provide full electrical compliance with ISO 7816-3, EMV® 4.2, and NDS specifications. It is derived from the 73S8024RN industry-standard electrical interface, but adds support for 1.8V smart card applications. The 73S8014BN has been optimized to match set-top box/A/V conditional access applications. The optimization adds functionality while creating a device with a smaller pin count. For NDS applications requiring an on-chip adjustable POR, see the Maxim 73S8024RN series of interface ICs.

The 73S8014BN interfaces with the host processor through the same bus (digital I/Os) as the 73S8024RN and most other 8024 type devices. As a result, the 73S8014BN is a very attractive cost-reduction path from traditional 8024 ICs.

Interfacing with the system controller is done through a control bus, composed of digital inputs to control the 73S8014BN, and one interrupt output to inform the system controller of the card presence, device readiness and faults.

The card clock can be generated by an on-chip oscillator using an external crystal or by connection to an externally supplied clock signal. In addition, the clock divider provides divisor values of divide by 1, 2, 4, and 8 that are controlled through a single pin.

The 73S8014BN incorporates an ISO 7816-3 activation/deactivation sequencer that controls the card signals. Level-shifters drive the card signals with the selected card voltage (1.8V, 3V, or 5V), coming from an internal low dropout (LDO) voltage regulator. This LDO regulator is powered by a dedicated power-supply input, V_PC. Digital circuitry is powered separately by a digital power supply, V_DD. With its embedded LDO regulator, the 73S8014BN is a cost-effective solution for any application where a 5V (typically -5% +10%) power supply is available.

Emergency card deactivation is initiated upon card extraction or upon any fault detected by the protection circuitry. The fault can be a card overcurrent, V_CC undervoltage, or power-supply fault (V_DD). The card overcurrent circuitry is a true current-detection function, as opposed to V_CC voltage drop detection, as usually implemented in non-Maxim 8024 interface ICs.

The 73S8014BN contains a power-down mode with typical power consumption of 1µA on each of the V_DD and V_PC supplies. The power-down mode is controlled through existing control pins without the need for a dedicated control pin.