Notes on hardware design of kt148a voice chip IC

2. chip explain

The chip is SOC programme , Integrated with a 16 Bit MCU, And an audio decoder aDSP, Hard decoding is adopted , It ensures the stability and sound quality of the system . The small package size can better meet the needs of embedding other products

 

2.1  Pin instructions

 

Pad No	Pad Name	ATTR	Description describe
1	GND	Power	Negative pole of power supply
2	PB9	I/O	Busy The signal = Play output low idle output high Multiplex serial port download , Connect MCU perhaps USB turn TTL Of RX foot
3	PB1	I/O	[ONELINE-DATA] One line serial port input terminal Multiplex serial port download , Connect MCU perhaps USB turn TTL Of TX foot
4	PB0	I/O	KEY Key -- test IO-- Trigger to the ground and play
5	SPK1	Out	There is no difference between positive and negative , Support 8 ohm 0.5W
6	SPK2	Out	There is no difference between positive and negative , Support 8 ohm 0.5W
7	VDDIO	Power	Internal to the chip LDO Output , Maximum 100mA
8	VBAT	Power	Positive pole of power supply

1、 Precautions for power supply ：

(1)、 It is recommended to supply power to the chip , Achieve 5V Power supply , The higher the voltage, the higher the power of the chip driving the horn , The louder the sound

(2)、 If it is [3.3--4.2V] Lithium battery scenario , The positive pole of the power supply goes directly into the chip 8 Just feet

(3)、 If it is a dry battery power supply scenario , The positive pole of the power supply also goes directly into the chip 8 foot

(4)、 If extra low voltage power supply is required , Such as 2V--3V Between the button batteries , Suggested chip 7 Feet and 8 The pin is directly short circuited , Then connect the positive pole of the power supply

2、 Quick test instructions ：

==》 Chip is the first 4 The foot is the test foot , Connect a button or tweezers to the ground to trigger , Will play the next voice

==》 Connect the speaker , Then after the power supply , You can use the second 4 Foot to ground test

2.2 GPIO Electrical characteristics

IO Input features
Symbol	Parameters	Minimum	A typical	Maximum	Company	Testing conditions
VIL	Low-Level Input Voltage	-0.3	-	0.3*VDD	V	VDDIO=3.3V
VIH	High-Level Input Voltage	0.7VDDIO	-	VDDIO+0.3	V	VDDIO=3.3V
IO output characteristic
Symbol	Parameters	Minimum	A typical	Maximum	Company	Testing conditions
VOL	Low-Level Output Voltage	-	-	0.33	V	VDDIO=3.3V
VOH	High-Level Output Voltage	2.7	-	-	V	VDDIO=3.3V

2.3 GPIO The internal characteristics of

Port	General Output	High Drive	Internal Pull-Up Resistor	Internal Pull-Down Resistor	Comment
PB0,PB1	8mA	64mA	10K	60K	1、PB0 & PB1 default pull down 2、internal pull-up/pull-down resistance | accuracy ±20%
PB9	8mA		10K	60K