Datasheet

DS_8023C_019 73S8023C Data Sheet
Rev. 1.5 5
1 Pin Description
1.1 Card Interface
Name Pin Description
I/O 9 Card I/O: Data signal to/from card. Includes a pull-up resistor to V
CC.
AUX1 11 AUX1: Auxiliary data signal to/from card. Includes a pull-up resistor to V
CC.
AUX2 10 AUX2: Auxiliary data signal to/from card. Includes a pull-up resistor to V
CC.
RST 14 Card reset: Provides reset (RST) signal to card.
CLK 13
Card clock: Provides clock (CLK) signal to card. The rate of this clock is
determined by crystal oscillator frequency and CLKDIV selections.
PRES 7
Card Presence switch: Active high indicates card is present. Includes a
pull-down current source.
PRES
6
Card Presence switch: Active low indicates card is present. Includes a pull-up
current source.
VCC 15
Card power supply: Logically controlled by sequencer, output of DC-DC
converter. Requires an external filter capacitor to the card GND.
GND 12 Card ground.
1.2 Miscellaneous Inputs and Outputs
Name Pin Description
XTALIN 23
Crystal oscillator input: can either be connected to crystal or driven as a
source for the card clock.
XTALOUT 24
Crystal oscillator output: connected to crystal. Left open if XTALIN is being
used as external clock input.
VDDF_ADJ 17
V
DD
fault threshold adjustment input: this pin can be used to adjust V
DDF
value (that controls deactivation of the card). Must be left open if unused.
NC 4 Non-connected pin. Must be left open.
1.3 Power Supply and Ground
Name Pin Description
VDD 3, 20
System controller interface supply voltage: Supply voltage for internal power
supply and DC-DC converter power supply source.
GND 1 DC-DC converter ground.
GND 21 Digital ground.
LIN 2
External inductor. Connect external inductor from pin 2 to V
DD
. Keep the
inductor close to pin 2.