73S 8024C Demo Board User Manual UM_8024C_061
10 Rev. 1 .3
Table 5: 73S8024C Miscellaneous Pins
Name Pin # Description
XTALIN 24 C r ystal oscill ator i nput: can either be connected to cryst al or driven as a
source for th e card clock.
XTALOUT 25 C r ystal oscill ator outp ut: connected to crystal. Left open i f XTALIN is being
used as external clock input.
VDDF_ADJ 18 VDD fault thr eshold adj ust ment i nput: this pin can be used t o adj ust the VDDF
val ues (co ntrol s deactivation of the car d) . Must be left open if unused.
NC 5,7 Non-connected pin.
Table 6: 73S8024C Po wer and Ground Pins
VDD 21 System i nterface supply volt age and suppl y voltage for in ternal circuitry.
VPC 6 DC-DC converter power supply source.
GND 4 DC-DC converter ground.
GND 22 Digital g rou nd.
LIN 5 E xternal i nductor. Connect external in duct or from pi n 2 to VPC. Keep the
inductor close to pi n 2.
Table 7: 72S8024C Mi cr ocon tr o ll er In t erfac e P i ns
Name Pin # Description
CMDVCC
Command VC C ( negative assertion): Logic l ow on thi s pin ca uses the LDO
regulator to ramp the V CC supply to the ca r d and initiates a car d activat ion
sequence , if a card is pr esent.
5V/#V 3 5 volt / 3 volt card se lection: Log ic one selects 5 volts for V CC and card
interface, logic low selects 3 volt operation.
When the part is to be used with
a si ngl e card volt age, th is pin should be tied to either GND or VDD. However,
it includes a high impedance pull-up resistor to default this pin high
(se l ection of 5V card) wh en not co nnected.
PWRDN 8 Power Down control input. Active high. Wh en the Power Down mode i s set
high, all in ternal anal og functions are disab led to place th e 73S8024C in its
lowest p ower consumption mode. The P ower Down mode i s only allow ed
out of a card session (i.e. when CM D VC C = 1)
CLKDIV1
CLKDIV2
1
2 S ets the di vide ratio from the XTAL oscillator (or external clock input) to the
car d clock. Th ese pins incl ude pull-down resistors.
0 0 XTALIN/8
1 0 XTALIN
OFF 23 Int er r upt signal to the pr ocessor. A ctive low - multi-function indicatin g fault
conditi ons and /or card presence. Open drain output configuration; includes
an int er nal 22 kΩ pull-up t o VDD.
RSTIN 20 Reset I nput: This sign al is the reset command to th e card.
I/OUC 26 Syste m controller data I/O to /from the card. Include s a pull-up resisto r to V DD.
AUX1UC 27 Syst em cont r oller auxili ary dat a I/O to/from th e card. In cludes a pul l -up
resistor to VDD.
AUX2UC 28 Syst em cont r oller auxili ary dat a I/O to/from th e card. In cludes a pul l -up
resistor to VDD.