21 HW Processor (HWP) and Sound Output
S1C31D50/D51 TECHNICAL MANUAL
Seiko Epson Corporation
21-3
(Rev. 2.00)
21.2 Output Pins and External Connections
21.2.1 List of Output Pins
Table 21.2.1.1 lists the S1C31D50/D51 SDAC output pins.
Table 21.2.1.1 S1C31D50/D51 SDAC Output Pins
Pin name
I/O
Initial status
Function
SDACOUT_P
O
O (L)
SDAC positive sound signal output
SDACOUT_N
O
O (L)
SDAC negative sound signal output
The SDAC output pins are shared with general-purpose I/O ports and are initially set as the SDAC pins. If the
Sound play function is not used or it is used with T16B Ch.0, these pins can be switched to general-purpose I/O
port pins. For details, refer to the “I/O Ports” chapter.
Note: If the audio amplifier has an enable signal input, use a general-purpose I/O port pin to output the
external amplifier enable signal.
Also, in addition to SDAC, the S1C31D51 can output the sound signal through the T16B Ch.0 TOUT.
Table 21.2.1.2 lists the S1C31D51 output pins when T16B is selected as the sound output destination.
Table 21.2.1.2 S1C31D51 T16B Ch.0 Sound Signal Output Pins
Pin name
I/O
*
Initial status
Function
TOUT00
O
O(L)
T16B Ch.0 sound signal output
TOUT01
O
O(L)
T16B Ch.0 sound signal output
*
Indicates the status when the pin is configured for T16B Ch.0.
Notes: • When using T16B Ch.0 for sound output, the T16B Ch.0 output functions must be assigned
to the ports.
• T16B Ch.0 cannot be used while the S1C31D51 is outputting sound through the T16B Ch.0 TOUT.
21.2.2 External Connections
Figures 21.2.2.1 and 21.2.2.2 show external circuit examples to input the SDAC sound signals to an external audio
amplifier. The circuit configuration and component values should be modified according to the specifications of the
audio amplifier to be used.
Single mode
S1C31 SDAC
Enable control
Low-pass filter
(Cutoff: 8 kHz)
C
IN
R
IN
SDACOUT_N
Pxx
510 Ω
C
IN
R
IN
Enable
IN-
Use a pull-down resistor if the audio amplifier enters sleep state by a low level input to the enable pin.
(Confirm the specification as it depends on the amplifier.)
IN+
39 µF
39 µF
510 Ω
Audio amplifier
Figure 21.2.2.1 Single Mode Connection Example
Differential mode
SDACOUT_P
S1C31 SDAC
Audio amplifier
Enable control
Low-pass filter (Cutoff: 8 kHz)
510 Ω
C
IN
R
IN
39 µF
39 µF
510 Ω
SDACOUT_N
Pxx
510 Ω
C
IN
R
IN
Enable
IN-
Use a pull-down resistor if the audio amplifier enters sleep state by a low level input to the enable pin.
(Confirm the specification as it depends on the amplifier.)
IN+
39 µF
39 µF
510 Ω
Figure 21.2.2.2 Differential Mode Connection Example
Refer to Application Note for connecting with a buzzer.