CH455
CH455 is LED drive and keyboard control chip manufactured by Unknown Manufacturer.
Features
- Set display current drive layer internally, the current of segment is no less than 25m A, the current of word is no less than 160m A.
- Display scan control dynamically, support 8×4 or 7×4, directly drive four bits number LED or thirty two LEDs.
- Internal limit current, set eight level light control via space percentage.
- Set 28-key keyboard control, based on 7×4 matrix scan..
- Set pull-down resistor internal while key-press, glitter removable.
- Supply keyboard interrupt active with low-level, and supply key-press release token to check the key is pressed or release.
- High speed two wires serial interface, the speed of clock varies from 0 to 4MHz, patible with I2C bus, save pins.
- Set turn on power to reset, 2.7V~5V power.
- Support low exhaust sleep mode to save energy, awoke via press key or mand.
- Set clock surge circuit internally, the external clock or surge equipment is not necessary, resister to be disturbed.
- Supply DIP18, SOP18 and SOP16 package without lead, patible with Ro HS, the function and pins are part patible with CH450 .
English Data Sheet of CH455
3. Package
Package DIP18 SOP18 SOP16
Width of plastic 7.62mm 300mil 7.62mm 300mil 3.9mm 150mil
Pitch of pin 2.54mm 100mil 1.27mm 50mil 1.27mm 50mil
Instruction of package Dual in-line package of 18-pin Small outline package of 18-pin Small outline package of 16-pin
Ordering CH455K CH455H CH455G
4. Pins
Pin No. DIP18/SOP18
11 4 9,10 12,13 14,15 16
1,5 6,7
2 18
SOP16 14 8
12,13 15,16
1,2 3
5,9 10,11
6 No
Pin Name VCC GND SEG0
～SEG6
SEG7 DIG0 ～DIG3
SCL...
