Epson Photo750 manual Timer Circuit, Eeprom Control Circuit, Head Drive Circuit

EPSON Stylus Photo 750 Revision A

2.2.2.4 Timer Circuit

The timer of this printer uses reset/timer IC(IC8). The timer keeps record of how long the printer is OFF and uses it information to judge it the initial cleaning should be performed or not when the power it turned ON next time. The data in the IC is backed up by the lithium battery.

2.2.2.5 EEPROM Control Circuit

This printer uses non-volatile memory EEPROM(IC7). When turning the power ON, EEPROM outputs data to the gate array(IC2) and records the data when turning the power OFF. The data which EEPROM will record are followings;

„Ink Consumption Counter (black/color)

„Frequency of Cleaning

„Destination Data

„CPSI Pass Word

„Other various setting values

+5V

		AT93C46				E05B58**
8		(IC7)		1	206	(IC2)
		Vcc	CS					EECS
	6	ORG	SK	2	205
						EECK
5					204
		GND	DI	3
							EECO
					203
			DO	4
						EECI

op07

Figure 2-7. EEPROM Control Circuit

2.2.2.6 Head Drive Circuit

Head drive circuit of this printer consists of the following circuits.

†Driven voltage wave form circuit

This circuit consists of HIC(IC14) and terminal transistor, and generates drive wave which will be charged to each PZT.

				+42
				F1
CXA20996(IC14)					CN9
		VCC45	22		27	VHV
A0			23		26
	Vcc45_2
A1		NPNB 20			25	COM
A2		FB	18			COM
A3		PNPB	16		24	COM
CLK1					23
			+5			COM
CLK2
/FLOOR		VCC5	24
/RST
DATA					22	GND2
DCLK					21
/E						GND2
VOUTGND 14					20	GND2
					19
						GND2
E05B58**(IC2)
HWA0		SWC0 190		1	BCO
		SWC1	189	2	CCO
HWA1			184	5
HWA2		HLAT			LAT
HWA3	HNCHG		173	16	NCHG
HWCLK1			174	14
HWCLK2		HCLK			CLK
/HWFLR		IECLK	175
/HWRST			176	12
		HSI1			SI1
HWSDATA			177	11
HWSCLK		HSI2			SI2
/HWSLAT			178	10
		HSI3
					SI3
		HSI4	179	9	SI4
			180	8
		HSI5			SI5
			181	7
		HSI6			SI6
				3	THM
TMP95C061(IC1)				+5
			AN0 105	18	GND
				17
					GND
				15
					GND
				13
					GND
				6
					GND
				4
					GND

op08

Figure 2-8. Common Drive Circuit

Operating Principles Operating Principles of Electric Circuit 35