71M6543F Datasheet, PDF (62/157 Pages) Maxim Integrated Products – Selectable Gain of 1 or 8 for One Current Energy Meter ICs Metrology Compensation

71M6543F/H and 71M6543G/GH Data Sheet
DIO Data Register
Direction Register:
0 = input, 1 = output
LCD_SEGDIO51[5:0] to LCD_SEGDIO55[5:0]
(I/O RAM 0x2443[5:0] to 0x2447[5:0])
51 52 53 54 55 – – –
LCD_SEGDIO51[0] to LCD_SEGDIO55[0]
(I/O RAM 0x2443[0] to 0x2447[0])
51 52 53 54 55 – – –
LCD_SEGDIO51[1] to LCD_SEGDIO55[1]
(I/O RAM 0x2443[1] to 0x2447[1])
2.5.10.3 LCD Drivers
The LCD drivers are grouped into up to six commons (COM0 – COM5) and up to 56 segment drivers.
The LCD interface is flexible and can drive 7-segment digits, 14-segment digits or enunciator symbols.
A voltage doubler and a contrast DAC generate VLCD from either VBAT or V3P3SYS, depending on the
V3P3SYS voltage. The voltage doubler, while capable of driving into a 500 kΩ load, is able to generate a
maximum LCD voltage that is within 1 V of twice the supply voltage. The doubler and DAC operate from
a trimmed low-power reference.
The configuration of the VLCD generation is controlled by the I/O RAM field LCD_VMODE[1:0] (I/O RAM
0x2401[7:6]). It is decoded into LCD_EXT, LDAC_E, and LCD_BSTE. Table 52 details the
LCD_VMODE[1:0] configurations.
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