Rainbow Electronics DS2781 - Manual (Page 4)

DS2781: Two-Cell Standalone Fuel Gauge IC
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EEPROM RELIABILITY SPECIFICATION
(V
PLS
= 2.5V to 10V, T
A
= -20°C to +70°C, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
EEPROM Copy Time t
EEC
15 ms
EEPROM Copy Endurance N
EEC
T
A
= +50°C 50,000 cycles
Note 1: All voltages are referenced to VSS.
Note 2: Factory calibrated accuracy. Higher accuracy can be achieved by in-system calibration by the user.
Note 3: Accumulation Bias register set to 00h. Current Offset Bias register set to 00h. NBEN bit = 0.
Note 4: Parameters guaranteed by design.
Note 5: Internal voltage regulator active.
PIN DESCRIPTION
PIN NAME FUNCTION
1 VB Internal Supply. Bypass to VSS with a 0.1µF capacitor.
2 VSS
Device Ground. Connect directly to the negative terminal of the cell stack. Connect the
sense resistor between VSS and SNS.
3 VIN
Voltage Sense Input. The voltage of the battery pack is monitored through this input pin
with respect to the VSS pin.
4 VPLS
Power-Supply Input. Connect to the positive terminal of the battery pack through a
decoupling network.
5 DQ
Data Input/Output. 1-Wire data line. Open-drain output driver. Connect this pin to the
DATA terminal of the battery pack. This pin has a weak internal pulldown (I
PD
) for sensing
pack disconnection from host or charger.
6 OVD
1-Wire Bus Speed Control. Input logic level selects the speed of the 1-Wire bus. Logic 1
selects overdrive (OVD) and Logic 0 selects standard timing (STD). On a multidrop bus,
all devices must operate at the same speed.
7 SNS
Sense Resistor Connection. Connect to the negative terminal of the battery pack.
Connect the sense resistor between VSS and SNS.
8 PIO
Programmable I/O Pin. Can be configured as input or output to monitor or control user-
defined external circuitry. Output driver is open drain. This pin has an weak internal
pulldown (I
PD
).