Datasheet
71M6511/71M6511H 
Single-Phase Energy Meter IC 
DATA SHEET  
NOVEMBER 2010 
Page: 94 of 98  © 2005–2010 Teridian Semiconductor Corporation  V2.7 
A Maxim Integrated Products Brand 
Pin Descriptions 
Power/Ground Pins 
Name  Pin #  Type  Description 
GNDA    49, 58  P  Analog ground: This pin should be connected directly to the ground plane. 
GNDD    1  P  Digital ground: This pin should be connected directly to the ground plane. 
V3P3A    50  P  Analog power supply: A 3.3V power supply should be connected to this pin. 
V3P3D    9  P  Digital power supply: A 3.3V power supply should be connected to this pin. 
VBAT  46  P 
Battery backup power supply. A battery or super-capacitor should be connected between 
VBAT and GNDD. If no battery is used, connect VBAT to V3P3D.  
V2P5  47  O 
Output of the internal 2.5V regulator. A 0.1µF capacitor to GNDA should be connected to this 
pin. 
VLCD  62  P  LCD power supply. A DC source of 3.3V to 5.0V should be connected to this pin. 
Analog Pins 
Name  Pin #  Type  Circuit  Description 
IA  54  I  6 
Line Current Sense Input: This pin is a voltage input to the internal A/D converter. 
Typically, it is connected to the output of a current transformer or shunt resistor. If 
the pin is unused it must be connected to V3P3A or tied to the IB pin. 
VA  51  I  6 
Line Voltage Sense Input: This pin is a voltage input to the internal A/D converter. 
Typically, it is connected to the output of a resistor divider. If the pin is unused it 
must be tied to V3P3A. 
IB  53  I  6 
Line Current Sense Input: This pin is a voltage input to the internal A/D converter. 
Typically, it is connected to the output of a current transformer or shunt resistor. If 
the pin is unused it must be connected to V3P3A or tied to the IA pin. 
V1  56  I  7 
Comparator Input: This pin is a voltage input to the internal comparator. The voltage 
applied to the pin is compared to an internal reference voltage of 1.5V. If the input 
voltage is above the reference, the comparator output will be high (1). If the 
comparator output is low, a voltage fault will occur. See the precautions in the 
Applications Section for terminating this pin. 
VREF  55  O  9 
Voltage Reference for the ADC. A 0.1µF capacitor to GNDA should be connected to 
this pin. 
VBIAS  52  O  9 
This pin outputs the reference voltage used by the power fault detection circuit. A 
1,000pF capacitor to GND should be connected to this pin. 
XIN 
XOUT  
59 
61 
I  8 
Crystal Inputs: A 32kHz style crystal should be connected across these pins. 
Typically, a 20pF capacitor is also connected from each pin to GNDA. It is important 
to minimize the capacitance between these pins. See the crystal manufacturer 
datasheet for details. 
VDRV  7  O  4  Voltage boost output. 
Pin types: P = Power, O = Output, I = Input, I/O = Input/Output 
The circuit number denotes the equivalent circuit, as specified under “I/O Equivalent Circuits”. 










