参数资料
型号: 73S8010R-DB
厂商: Maxim Integrated Products
文件页数: 9/25页
文件大小: 0K
描述: BOARD DEMO 73S8010R 28-SOIC
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 1
系列: *
DS_8010R_022
73S8010R Data Sheet
Rev. 1.6
17
3.3
Power Supply and Voltage Supervision
The Teridian 73S8010R smart card interface IC incorporates a LDO voltage regulator. The voltage
output is controlled by the digital input 5V/
#V. This regulator is able to provide either 3 V or 5 V card
voltage from the power supply applied on the VPC pin.
Digital circuitry is powered by the power supply applied on the VDD pin. VDD also defines the voltage
range to interface with the system controller.
Three voltage supervisors constantly check the presence of the voltages VDD, VPC and VCC. A card
deactivation sequence is forced upon fault of any of these voltage supervisors. The two voltage
supervisors for VPC and VCC are linked so that a fault is generated to activate a deactivation sequence
when the voltage VPC becomes lower than VCC. This allows the 73S8010R to operate at lower VPC
voltage when using 3 V cards only.
The voltage regulator can provide a current of at least 90 mA on VCC which easily complies with the
EMV 4.0 specification. The VPC voltage supervisor threshold values are defined from the EMV 4.0
standard. A third voltage supervisor monitors the VDD voltage. It is used to initialize the ISO-7816-3
sequencer at power-on, and to deactivate the card at power-off or upon a fault. The voltage threshold of
the VDD voltage supervisor is internally set by default to 2.3 V nominal. However, it may be desirable in
some applications to modify this threshold value. The pin VDDF_ADJ (pin 18 in the SO package, pin 17
in the QFN package) is used to connect an external resistor REXT to ground to raise the VDD fault voltage
to another value VDDF. The resistor value is defined as follows:
REXT = 56 k
Ω / (V
DDF - 2.33)
An alternative (more accurate) method of adjusting the VDD fault voltage is to use a resistive network of
R3 from the pin to supply and R1 from the pin to ground (see Figure 4). In order to set the new threshold
voltage, the equivalent resistance must be determined. This resistance value will be designated Kx. Kx
is defined as R1/(R1+R3). Kx is calculated as:
Kx = (2.789 / VTH) - 0.6125 where VTH is the desired new threshold voltage.
To determine the values of R1 and R3, use the following formulas.
R3 = 24000 / Kx
R1 = R3*(Kx / (1 – Kx))
Taking the example above, where a VDD fault threshold voltage of 2.7 V is desired, solving for Kx gives:
Kx = (2.789 / 2.7) - 0.6125 = 0.42046.
Solving for R3 gives:
R3 = 24000 / 0.42046 = 57080.
Solving for R1 gives:
R1 = 57080 *(0.42046 / (1 – 0.42046)) = 41412.
Using standard 1 % resistor values gives R3 = 57.6 K
and R1 = 42.4 K.
These values give an equivalent resistance of Kx = 0.4228, a 0.6% error.
If the 2.3 V default threshold is used, this pin must be left unconnected.
相关PDF资料
PDF描述
DD-DB1-AL202C-FB DEV BD 20X2 LCD BLU TXT BLK BL
NCP301LSN30T1G IC DETECTOR VOLTAGE 3.0V 5TSOP
DD-DB1-AL202C-FW DEV BD 20X2 LCD WHT TXT BLK BL
EET-UQ2E102EA CAP ALUM 1000UF 250V 20% SNAP
NCP303LSN27T1G IC VOLTAGE DETECT 2.7V 5TSOP
相关代理商/技术参数
参数描述
73S8010R-IL/F 功能描述:I2C 接口集成电路 Smart Card Interface ISO7816-3 & EVM4.0 RoHS:否 制造商:NXP Semiconductors 电源电压-最大:5.5 V 电源电压-最小:2.3 V 最大工作频率:400 KHz 最大工作温度:+ 85 C 封装 / 箱体:TSSOP-16
73S8010R-ILR/F 功能描述:I2C 接口集成电路 Smart Card Interface ISO7816-3 & EVM4.0 RoHS:否 制造商:NXP Semiconductors 电源电压-最大:5.5 V 电源电压-最小:2.3 V 最大工作频率:400 KHz 最大工作温度:+ 85 C 封装 / 箱体:TSSOP-16
73S8010R-IM/F 功能描述:I2C 接口集成电路 Smart Card Interface ISO7816-3 & EVM4.0 RoHS:否 制造商:NXP Semiconductors 电源电压-最大:5.5 V 电源电压-最小:2.3 V 最大工作频率:400 KHz 最大工作温度:+ 85 C 封装 / 箱体:TSSOP-16
73S8010R-IM/F1 功能描述:I2C 接口集成电路 RoHS:否 制造商:NXP Semiconductors 电源电压-最大:5.5 V 电源电压-最小:2.3 V 最大工作频率:400 KHz 最大工作温度:+ 85 C 封装 / 箱体:TSSOP-16
73S8010R-IM/F2 功能描述:I2C 接口集成电路 RoHS:否 制造商:NXP Semiconductors 电源电压-最大:5.5 V 电源电压-最小:2.3 V 最大工作频率:400 KHz 最大工作温度:+ 85 C 封装 / 箱体:TSSOP-16