HCS370_11 MICROCHIP [Microchip Technology], HCS370_11 Datasheet - Page 5

• Manufacturer Part Number: HCS370_11
• Manufacturer: MICROCHIP [Microchip Technology]

2.0
As shown in the typical application circuits (Figure 2-1),
the HCS370 is an easy device to use. It requires only
the addition of buttons and RF circuitry for use as the
encoder in your security application. A description of
each pin is described in Table 2-1. Refer to Figure 2-3
for information on the I/O pins.
TABLE 2-1:
The HCS370 will normally be in a low power SLEEP
mode. When a button input is taken high, the device will
wake-up, start the step-up regulator, and go through
the button debounce delay of T
code is latched. In addition, the device will then read
the configuration options. Depending on the configura-
tion options and the button code, the device will deter-
mine what the data and modulation format will be for
the transmission. The transmission will consist of a
stream of code words and will be transmitted T
the button is pressed for as long as the buttons are held
down or until a time-out occurs. The code word format
can be either a code hopping format or a seed format.
The time-out time can be selected with the Time-out
Select (TSEL) configuration option. This option allows
the time-out to be set to 0.8s, 3.2s, 12.8s, or 25.6s.
When a time-out occurs, the device will go into SLEEP
mode to protect the battery from draining when a button
gets stuck. This option must be chosen to meet maxi-
mum transmission length regulatory limits which vary
by country.
2011 Microchip Technology Inc.
S5/SLEEP
Note:
SHIFT
Name
RFEN
STEP
DATA
LED
V
V
V
S0
S1
S2
S3
S4
DD
SS
IN
DEVICE DESCRIPTION
S0-S5 and SHIFT inputs have pull-down
resistors. V
step-up regulator is not used.
Number
Pin
10
11
12
13
14
PIN DESCRIPTIONS
1
2
3
4
5
6
7
8
9
IN
Switch input S0
Switch input S1
Switch input S2
Switch input S3
Switch input S4
Switch input S5, or SLEEP
output
SHIFT input
Step-up regulator input
Step-up pulses output
RF enable output
Ground reference
Transmission output pin
Open drain output for LED
with pull-up resistor
Positive supply voltage
should be tied high if the
Description
DB
before the button
PU
after
FIGURE 2-1:
2.05-5.5V
Note: Using SLEEP output low instead of grounding the resistor
Figure 2-1(A)
Figure 2-1(B)
Figure 2-1(C)
B0
B1
B2
B3
B4
B5
Tx2
divider reduces battery drain between transmissions
V
DD
S0
S1
S2
S2
S3
S4
SLEEP
SHIFT
SHIFT
Two Button remote with Step-up circuit
Tx1
DUAL Transmitter remote control
Six Button remote with PLL control
TYPICAL CIRCUITS
S0
S1
S2
S3
S4
S5
SHIFT
SHIFT
S0
S1
S2
S2
S3
S4
S5
SHIFT
SHIFT
RFEN
STEP
DATA
DATA
LED
V
V
V
DD
SS
IN
RFEN
RFEN
STEP
STEP
DATA
DATA
DATA
DATA
2.2 k
LED
Tx out
LED
V
V
1000 pF
V
V
V
V
DD
DD
SS
SS
IN
IN
Ω
V
HCS370
Tx out
DD
2N3904
330
1N4148
22
C
V
V
OUT
DS41111E-page 5
DD
μF
DD
μH
R
LED
R
D
E
LED
Tx out
ATA
NABLE
RF PLL
6V@1 mA
I
N
33k
10k
Ω
Ω