Not recommended for new designs.
Please use MCRF355 or MCRF450.
MCRF200
125 kHz microID
®
Passive RFID Device
Features
• Factory programming and memory serialization
(SQTP
SM
)
• One-time contactless programmable (developer
kit only)
• Read-only data transmission after programming
• 96 or 128 bits of One-Time Programmable (OTP)
user memory (also supports 48- and 64-bit
protocols)
• Typical operation frequency: 100 kHz — 400 kHz
• Ultra low-power operation (5
μA
@ V
CC
= 2V)
• Modulation options:
- ASK, FSK, PSK
• Data encoding options:
- NRZ Direct, Differential Biphase, Manchester
Biphase
• Die, wafer, PDIP or SOIC package options
• Factory programming options
Package Type
PDIP/SOIC
V
A
NC
I/O
RESET
1
2
3
4
8
7
6
5
V
B
NC
V
SS
V
CC
Note:
Pins 3, 4, 5 and 6 are for device test purposes only.
Pins 1 and 8 are for antenna connections.
DO NOT ground pin 5.
Description
The MCRF200 is a passive Radio Frequency Identifi-
cation (RFID) device for low-frequency applications
(100 kHz — 400 kHz). The device is powered by
rectifying an incoming RF signal from the reader. The
device requires an external LC resonant circuit to
receive the incoming RF signal and to send data. The
device develops a sufficient DC voltage for operation
when its external coil voltage reaches approximately 10
V
PP
.
This device has a total of 128 bits of user programmable
memory and an additional 12 bits in its configuration
register. In production volume, the MCRF200 is
programmed at the factory (Microchip SQTP – see
Technical Bulletin TB023). The device is a One-Time
Programmable (OTP) integrated circuit and operates as
a read-only device after programming.
Application
• Low-cost alternative for existing low-frequency
RFID devices
• Access control and time attendance
• Security systems
• Animal tagging
• Product identification
• Industrial tagging
• Inventory control
RF
Signal
Reader
Data
MCRF200
©
2005 Microchip Technology Inc.
DS21219J-page 1
MCRF200
Block Diagram
Modulation
Control
Data
Modulation
Circuit
Coil
Connections
Clock
Generator
V
CC
Rectifier
V
SS
Row
Decode
Memory
Array
Counter
Column
Decode
The configuration register includes options for commu-
nication protocol (ASK, FSK, PSK), data encoding
method, data rate, and data length.These options are
specified by the customer and factory programmed
during assembly. Because of its many choices of con-
figuration options, the device can be easily used as an
alternative or second source for most of the existing
low frequency passive RFID devices available today.
The device has a modulation transistor between the
two antenna connections (V
A
and V
B
). The modulation
transistor damps or undamps the coil voltage when it
sends data. The variation of coil voltage controlled by
the modulation transistor results in a perturbation of
voltage in reader antenna coil. By monitoring the
changes in reader coil voltage, the data transmitted
from the device can be reconstructed.
The device is available in die, wafer, PDIP, or SOIC
packages. Factory programming and memory serial-
ization (SQTP) are also available upon request for
large orders of 500,000 units or more. See TB023 for
more information on factory programming support.
DS21219J-page 2
©
2005 Microchip Technology Inc.
MCRF200
1.0
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings
(†)
Storage temperature ..............................................................................................................................- 65°C to +150°C
Ambient temperature with power applied................................................................................................-40°C to +125°C
Maximum current into coil pads ..............................................................................................................................50 mA
† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to
the device. This is a stress rating only and functional operation of the device at those or any other conditions
above those indicated in the operational listings of this specification is not implied. Exposure to maximum rating
conditions for extended periods may affect device reliability.
TABLE 1-1:
AC AND DC CHARACTERISTICS
All parameters apply across the
specified operating ranges unless Industrial (I): T
A
= -40°C to +85°C
otherwise noted.
Parameter
Clock frequency
Contactless programming time
Data retention
Coil current (Dynamic)
Operating current
Turn-on-voltage (Dynamic) for
modulation
Input Capacitance
I
CD
I
DD
V
A
V
B
V
CC
C
IN
Sym
F
CLK
T
WC
Min
100
—
200
—
—
10
2
—
Typ
—
2
—
50
5
—
—
2
—
—
—
Max
400
—
—
Units
kHz
sec
Years
μA
μA
V
PP
V
DC
pF
Between V
A
and V
B
V
CC
= 2V
For all 128-bit array
at 25°C
Conditions
©
2005 Microchip Technology Inc.
DS21219J-page 3
MCRF200
2.0
FUNCTION DESCRIPTION
2.1.2
POWER-ON RESET
The device contains three major building blocks. They
are RF front-end, configuration and control logic, and
memory sections. The block diagram is shown on page
1.
This circuit generates a Power-on Reset when the tag
first enters the reader field. The Reset releases when
sufficient power has developed on the V
DD
regulator to
allow correct operation.
2.1
RF Front-End
2.1.3
CLOCK GENERATOR
The RF front-end of the device includes circuits for
rectification of the carrier, V
DD
(operating voltage) and
high-voltage clamping. This section also includes a
clock generator and modulation circuit.
This circuit generates a clock based on the carrier
frequency from the reader. This clock is used to derive
all timing in the device, including the baud rate and
modulation rate.
2.1.4
2.1.1
RECTIFIER – AC CLAMP
The rectifier circuit rectifies RF voltage on the external
LC antenna circuit. Any excessive voltage on the tuned
circuit is clamped by the internal circuitry to a safe level
to prevent damage to the IC.
MODULATION CIRCUIT
The device sends the encoded data to the reader by
AM-modulating the coil voltage across the tuned LC
circuit. A modulation transistor is placed between the
two antenna coil pads (V
A
and V
B
). The transistor turns
on and off based on the modulation signal. As a result,
the amplitude of the antenna coil voltage varies with the
modulation signal. See Figure 2-1 for details.
FIGURE 2-1:
MODULATION SIGNAL AND MODULATED SIGNAL
MCRF200
V
A
Modulation
Signal
L
C
V
B
Modulation
Transistor
Amplitude
Modulation Signal
Modulated RF Signal
(across V
A
and V
B
)
t
DS21219J-page 4
©
2005 Microchip Technology Inc.
MCRF200
2.2
Configuration Register and
Control Logic
2.2.3
MODULATION OPTION
CB8 and CB9 determine the modulation protocol of the
encoded data. The available choices are:
•
•
•
•
ASK
FSK
PSK_1
PSK_2
The configuration register determines the operational
parameters of the device. The configuration register
can not be programmed contactlessly; it is
programmed during wafer probe at the Microchip
factory. CB11 is always a zero; CB12 is set when
successful contact or contactless programming of the
data array has been completed. Once CB12 is set,
device programming and erasing is disabled. Table 2-4
contains a description of the bit functions of the control
register.
When ASK (direct) option is chosen, the encoded data
is fed into the modulation transistor without change.
When FSK option is chosen, the encoded data is
represented by:
a)
Sets of 10 RF carrier cycles (first 5 cycles
→
higher amplitude, the last 5 cycles
→
lower
amplitude) for logic “high” level.
Sets of 8 RF carrier cycles (first 4 cycles
→
higher amplitude, the last 4 cycles
→
lower
amplitude) for logic “low” level.
2.2.1
BAUD RATE TIMING OPTION
The chip will access data at a baud rate determined by
bits CB2, CB3 and CB4 of the configuration register.
For example, MOD32 (CB2 =
0,
CB3 =
1,
CB4 =
1)
has
32 RF cycles per bit. This gives the data rate of 4 kHz
for the RF carrier frequency of 128 kHz.
The default timing is MOD128 (F
CLK
/128), and this
mode is used for contact and contactless program-
ming. Once the array is successfully programmed, the
lock bit CB12 is set. When the lock bit is set, program-
ming and erasing the device becomes permanently
disabled. The configuration register has no effect on
device timing until the EEPROM data array is
programmed (CB12 =
1).
b)
For example, the FSK signal for MOD40 is repre-
sented:
a)
b)
4 sets of 10 RF carrier cycles for data ‘1’.
5 sets of 8 RF carrier cycles for data ‘0’.
Refer to Figure 2-2 for the FSK signal with MOD40
option.
The PSK_1 represents change in the phase of the
modulation signal at the change of the encoded data.
For example, the phase changes when the encoded
data is changed from ‘1’ to ‘0’, or from ‘0’ to ‘1’.
The PSK_2 represents change in the phase at the
change on ‘1’. For example, the phase changes when
the encoded data is changed from ‘0’ to ‘1’, or from ‘1’
to ‘1’.
2.2.2
DATA ENCODING OPTION
This logic acts upon the serial data being read from the
EEPROM. The logic encodes the data according to the
configuration bits CB6 and CB7. CB6 and CB7
determine the data encoding method. The available
choices are:
• Non-return to zero-level (NRZ_L)
• Biphase Differential, Biphase Manchester
• Inverted Manchester
FIGURE 2-2:
ENCODED DATA AND FSK OUTPUT SIGNAL FOR MOD40 OPTION
Encoded Data ‘1’
5 cycles (HI)
5 cycles (LO)
Encoded Data ‘0’
4 cycles (HI)
4 cycles (LO)
40 RF cycles
40 RF cycles
©
2005 Microchip Technology Inc.
DS21219J-page 5