sh6616 SinoWealth Micro-Electronics Corp. Ltd, sh6616 Datasheet - Page 15

• Manufacturer Part Number: sh6616
• Description: 16k 4-bit Microcontroller
• Manufacturer: SinoWealth Micro-Electronics Corp. Ltd

7. LCD
The LCD has 16 common signal pads and 33 segment driver pads, a controller, LCD voltage generator. The controller consists of
display data RAM and a duty generator. The LCD data RAM is a dual port RAM that automatically transfers data to segment. The
LCD can be turned off with the internal LCDOFF register.
LCD frame frequency is controlled by 32.768KHz clock. Therefore, the 32.768KHz clock must be enabled before the LCD is turned
on. To save power, the main clock can be stopped and the 32.768KHz clock enabled to keep LCD on.
After osc32k is steady, setting VDE can enable the Voltage Pump circuit. LCD voltage is pumped to 4.5V if pump is enabled and
V
The LCD has two modes, 1/16 duty and 1/8 duty
Table 1. LCD Mode Control Register $1EH:
Table 2. LCDI1 and LCDI0 control the LCD driving current.
DD
is 3.0V.
LCDI1
$1EH.BIT3
$1EH.BIT2
$1EH.BIT1
$1EH.BIT0
0
0
1
1
LCDI0
0
1
0
1
Voltage pump enable (initially 0, disable pump)
LCD bias current control bit1 (initially 0)
LCD bias current control bit0 (initially 0)
0 set 8 duty (initially 0), 1 set 16 duty
LCD Bias Current
Minimum (Default)
Maximum
15
SH6616