hcs410 Microchip Technology Inc., hcs410 Datasheet - Page 5

• Manufacturer Part Number: hcs410
• Description: Keeloq Code Hopping Encoder And Transponder Keeloq Code Hopping Encoder And Transponder
• Manufacturer: Microchip Technology Inc.

2.0
The HCS410 can either operate as a normal code hop-
ping transmitter with one or two IFF keys (Figure 2-1)
or as purely an IFF token with two IFF keys (Figure 2-2
and Figure 2-3). When used as a code hopping trans-
mitter the HCS410 only needs the addition of buttons
and RF circuitry for use as a transmitter. Adding the
transponder function to the transmitter requires the
addition of an inductor and two capacitors as shown in
Figure 2-1 and Figure 2-2. A description of each pin is
given in Table 2-1. Table 2-2 shows the function codes
for using the HCS410.
FIGURE 2-1:
FIGURE 2-2:
FIGURE 2-3:
 2001 Microchip Technology Inc.
DEVICE OPERATION
1
2
3
4
1
2
3
4
1
2
3
4
COMBINED TRANSMITTER/
TRANSPONDER CIRCUIT
TRANSPONDER CIRCUIT
2-WIRE, 1 OR 2-KEY IFF
TOKEN
8
7
6
5
8
7
6
5
8
7
6
5
Data I/O
1 µF
1 µF
1 µF
RF
Preliminary
Figure 2-4 shows how to use the HCS410 with a 12V
battery as a code hopping transmitter. The circuit uses
the internal regulator, normally used for charging a
capacitor/battery in LC mode, to generate a 6V supply
for the HCS410.
FIGURE 2-4:
FIGURE 2-5:
FIGURE 2-6:
12V
LC1
LC0
220Ω
220Ω
100
100
15V
15V
Ω
Ω
HCS410 ENCODER WITH 12V
BATTERY
LED CONNECTION TO
S2/LED OUTPUT
LC PIN BLOCK DIAGRAM
1
2
3
4
S2/LED
8
7
6
5
Detector
Rectifier,
Damping,
Clamping
HCS410
6.3V
V
DD
30Ω
60k
DS40158E-page 5
Pulse
6.3V
Damp
Out
MOD
V
RF
DD