71m6521be Maxim Integrated Products, Inc., 71m6521be Datasheet - Page 51

• Manufacturer Part Number: 71m6521be
• Description: Energy Meter Ic
• Manufacturer: Maxim Integrated Products, Inc.

LCD Mode
In LCD mode, the data contained in the LCD_SEG registers is displayed, i.e. up to four LCD segments connected to each of the
pins SEG18 and SEG19 can be made to blink without the involvement of the MPU, which is disabled in LCD mode. The
V3P3D output pin is inactive in LCD mode.
This mode can be exited only by system power up, a timeout of the wake-up timer, or a push button. Figure 20 shows the
functional blocks active in LCD mode.
SLEEP Mode
In SLEEP mode, the battery current is minimized and only the Oscillator is active. The V3P3D output pin is inactive in LCD
mode. This mode can be exited only by system power-up, a timeout of the wake-up timer, or a push button event. Figure 21
shows the functional blocks active in SLEEP mode.
V1.0
CE
CE Data RAM
FIR
Analog circuits:
PLL, ADC, VREF, BME, etc.
MPU clock rate
MPU_DIV
ICE
DIO Pins
Watchdog Timer
LCD
EEPROM Interface (2-wire)
EEPROM Interface (3-wire)
UART
Optical TX modulation
Flash Read
Flash Page Erase
Flash Write
RAM Read and Write
Wakeup Timer
Crystal oscillator
DRAM data preservation
V3P3D voltage output
Circuit Function
Table 59: Available Circuit Functions (“—“ means “not active)
© 2005-2008 TERIDIAN Semiconductor Corporation
System Power
(from PLL)
MISSION
4.92MHz
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
(7/8 of 32768Hz)
BROWNOUT
Battery Power (nonvolatile Supply)
Yes (16kb/s)
Yes (8kb/s)
28.672kHz
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
--
--
--
--
--
Energy Meter IC
LCD
Yes
Yes
Yes
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
71M6521BE
DATA SHEET
SLEEP
Yes
Yes
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
JANUARY 2008
Page: 51 of 97