HTRC11001 Philips Semiconductors, HTRC11001 Datasheet - Page 7

• Manufacturer Part Number: HTRC11001
• Description: HITAG reader chip
• Manufacturer: Philips Semiconductors

Philips Semiconductors
8.6
The HTRC11001T can be switched into the Idle mode via
setting bit PD = 1 and resetting bit PD_MODE = 0
(see Table 3). In this Idle mode, only the oscillator and a
few other system components are active.
It is also possible to switch the HTRC11001T completely
off. This is achieved by the Power-down mode (bit PD = 1
and bit PD_MODE = 1). Within this mode also the clock
oscillator is switched off. This reduces the supply current
of the HTRC11001T to less than 20 A.
8.7
The communication between the HTRC11001T and the
microcontroller is done via a 3-wire digital interface. The
interface is operated by the following signals:
Pins SCLK and DIN are realized as Schmitt-trigger inputs.
Pin DOUT is an open-drain output with an internal pull-up
resistor.
8.7.1
Every communication between the HTRC11001T and the
microcontroller begins with an initialization of the serial
interface. The interface initialization condition is a
LOW-to-HIGH transition on pin DIN while pin SCLK is at
HIGH level (see Fig.3).
2001 Nov 23
handbook, full pagewidth
Clock pulse on pin SCLK
Data input on pin DIN
Data output on pin DOUT.
HITAG reader chip
Idle and Power-down mode
Serial interface
C
OMMUNICATION PROTOCOL
SCLK
DIN
DOUT
initialization
Fig.3 Serial interface communication protocol.
D7
t su
D6
t h
7
D1
All commands transmitted to the HTRC11001T serial
interface start with the Most Significant Bit (MSB).
Input DIN and output DOUT are valid when pin SCLK is at
HIGH level.
8.7.2
Connecting pin MODE to V
SCLK and the DIN input signals. This mode offers
improved immunity against noise and interference
(glitches) on these interface signals. It is intended to be
used in the so called ‘active antenna applications’ where
the microcontroller and the reader communicate via long
signal lines (e.g. 1 meter).
In other applications pin MODE has to be connected to
ground (pin V
For a detailed description of this feature, refer to the
application note “AN 98080 Read/Write devices based on
the HITAG Read/Write IC HTRC110” .
D0
D7
G
LITCH FILTER
SS
D6
).
DD
enables digital filtering of the
D1
HTRC11001T
Product specification
D0
MGW268