Kenwood TK-260G, TK-270G service manual Circuit DESCRIPTION/SEMICONDUCTOR Data, UPB1509GV IC301

TK-260G/270G

CIRCUIT DESCRIPTION/SEMICONDUCTOR DATA

8. CONTROL SYSTEM

Keys and channel selector circuit.

The signal from the keys and channel selector are directly input to the microprocessor, as shown in fig. 10.

Pin No.	Name	I/O	Active	Function
60	VSS	-	-
61	OSC	I/O	-	Oscillation terminal
62	CE	I	H	Chip enable. Serial data transfer terminal.
				Connected to the microprocessor.
63	CL	I		Synchronizing clock. Serial data transfer terminal.

Channel selector

25 EN1

16 EN2

27 EN3

TK-260G

PTT 3

KEYAD 87

IC13

-COM

KIN4 KIN3 KIN2 KIN1 KIN0 KOUT3 KOUT2 KOUT1 KOUT0

CN1

PTT SW

5M

47k

47k

100k

LAMP

SW

MONI

SW

			Connected to the microprocessor.
64 DI	I	-	Trnsfer data. Serial data transfer terminal.
			Connected to the microprocessor.

UPB1509GV (IC301)

■Pin connection diagram

CN501

1

5

Pin No.	Pin Name
1	VCC1
2	IN

TK-270G
1	2	3	A
4	5	6	B
7	8	9	C
∗	0	#	D

Fig. 10 Control system

2

3

4

6

7

8

3	IN
4	GND
5	SW1
6	SW2
7	OUT
8	VCC2

SEMICONDUCTOR DATA

LCD Driver : LC75823W (Display UNIT IC501)

(TK-270G only)

■Block diagram

	COM1 COM2 COM3	S52 S51		S1
VDD1	COMMON		LATCH & DRIVER
VDD2	DRIVER
INH
			SHIFT REGISTER
OSC	CLOCK			ADDRESS
	GENERATOR			DETECTOR
		DI	CL CE	VDDVSS

■Pin function

Pin No.		Name	I/O	Active		Function
1-52	S1-S52		O	-	Segment output for displaying data
					transferred form serial data.
53-55	COM1-COM3		O	-	Common drive output.
					Frame frequency fo=(fosc/384)Hz
56	VDD		-	-
					The display to turn off
57			I	L
		INH			INT=L : Turn off
					INT=H : Turn on
					Apply 2/3 the LCD drive bias voltage
58	VDD1		I	-	from outside. If 1/2 the bias is applied,
					connect to VDD2.
					Apply 1/3 the LCD drive bias voltage
59	VDD2		I	-	from outside. If 1/2 the bias is applied,
					connect to VDD1.

■Block diagram

D Q	D Q	D	Q
IN
CLK	CLK	CLK	OUT
IN
Q	Q		Q

SW1SW2

■Pin Fanction

Pin		Pin	Applied	Pin	Functions and uses
No.	name		voltage	voltage
1	VCC1		2.2-2.5	-	Power supply voltage pin for the input amplifier section and
					division circuit. Connect a bypass capacitor to this pin to reduce
					the high-frequency impedance with the ground (for example, 1000 pF).
2	IN		-	1.7-4.95	Signal input pin. Connect a coupling capacitor to this pin for
					DC cutting with an external circuit (for example, 1000 pF).
3			-	1.7-4.95	Input signal bypass pin. Connect a bypass capacitor to this
		IN
					pin to reduce the high-frequency impedance with the ground
					(for example, 1000 pF).
4	GND		0	-	Ground pin. Connect it with the ground pattern. The ground
					pattern on the PC board should be wide enough to minimize
					impedance.
5	SW1		H/L	-	Division ratio setting pin. The division ratio can be set by the
					following voltage:
								SW2
								H	L
						SW1	H	1/2	1/4
							L	1/4	1/2
					Connect a bypass capacitor to this pin to reduce the high-
6	SW2
					frequency impedance with the ground.
7	OUT		-	1.0-4.7	Division signal output pin. Emitter follower output. 0.1 Vpf or
					more can be output under 200-ohmload. Connect a coupling
					capacitor to this pin for DC cutting with an external circuit
					(for example,1000 pF).
8	VCC2		2.2-5.5	-	Power supply voltage pin for the output buffer circuit. Connect
					a bypass capacitor to this pin to reduce the high-frequency
					impedance with the ground (for example, 1000 pF).					21