fma1127da Fujitsu Microelectronics, Inc., fma1127da Datasheet - Page 16

• Manufacturer Part Number: fma1127da
• Description: Touch Sensor Controller
• Manufacturer: Fujitsu Microelectronics, Inc.

Touch Sensor Controller
Typical Application Circuit
Notes:
• The voltage range of VDD can be from 2.3V to 5.5V. If internal LDO is used, it should be from 3V to 5.5V.
• Pull-Up resistors are required for
• Each tuning capacitor is an optional component depending on PCB layout environment.
• The circuit above is a typical application circuit using an internal LDO.
• RESET_N pin should be connected to host MCU GPIO and needs an RC filter. (R1=10KΩ, C1=1uF)
• For LED control through DIO ports, sink current circuit is mandatory as shown above.
• I
14
resistor is typically used.
tional START condition which causes the TSC to wait indefinitely.
Recommendations to avoid such a noise glitch:
2
C has no recovery specification when clk is attacked by noise glitch or ESD. Sometimes ‘additional’ clock by noise glitch generates uninten-
1. Addition of serial resister on I
2. Addition of about capacitor on I
Fujitsu Microelectronics America, Inc.
size of capacitor depends on existing parasitic capacitance of the board (~Value ranging from 30pf to 300pf).
Touch PAD
Touch PAD
(From MCU)
RESET_N
Data Sensor
Tuning Cap
Touch_Sensor_1
Touch_Sensor_0
Touch_Sensor_4
Touch_Sensor_3
Touch_Sensor_2
Touch_Sensor_8
10K
I
2
2
C clock line and data line having values ranging from 100ohm to 500ohm.
C
1uF
2
R1
C clock line and data line and connect other end to ground. This would add some filtering mechanism. The
communication. For 5V application, 2K ohm resistor is typically used. For 3V application, 1K ohm
Touch_Sensor_2
Touch_Sensor_1
Touch_Sensor_0
C1
19
20
22
23
24
21
S2
DIO_2
S1
RESET_N
ID
S0
18
1
2K
2K
FMA1127DA
17
2
16
24N
3
15
4
14
5
13
CONFIG_1
CONFIG_0
DIO_8
AREF
TOSC
6
S8
(LED Control Circuit)
DIO_N
12
11
10
8
9
7
Touch_Sensor_8
Reference Sensor
Tuning Cap
X pF
VDD