DS2784G+T&R Maxim Integrated Products, DS2784G+T&R Datasheet - Page 17

• Manufacturer Part Number: DS2784G+T&R
• Description: IC FUEL GAUGE STND-ALONE 14-TDFN
• Manufacturer: Maxim Integrated Products

Specifications of DS2784G+T&R

• Function: Fuel, Gas Gauge/Monitor
• Battery Type: Lithium-Ion (Li-Ion), Lithium-Polymer (Li-Pol)
• Voltage - Supply: 2.5 V ~ 4.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 14-TDFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

VOLTAGE MEASUREMENT
Battery voltage is measured every 440ms on the V
and a 4.88mV resolution. The value is stored in the voltage register in two’s complement form and is updated every
440ms. Voltages above the maximum register value are reported at the maximum value; voltages below the
minimum register value are reported at the minimum value.
VOLTAGE REGISTER FORMAT
TEMPERATURE MEASUREMENT
The DS2784 uses an integrated temperature sensor to measure battery temperature with a resolution of 0.125°C.
Temperature measurements are updated every 440ms and placed in the temperature register in two’s complement
form.
TEMPERATURE REGISTER FORMAT
Note: Temperature and battery voltage (V
every 440ms.
CURRENT MEASUREMENT
The DS2784 continually measures the current flow into and out of the battery by measuring the voltage drop across
a low-value current-sense resistor, R
linearly converts peak-signal amplitudes up to 102.4mV as long as the continuous signal level (average over the
conversion cycle period) does not exceed ±51.2mV. The ADC samples the input differentially at 18.6kHz and
updates the current register at the completion of each conversion cycle (3.52s). Charge currents above the
maximum register value are reported as 7FFFh. Discharge currents below the minimum register value are reported
as 8000h.
CURRENT REGISTER FORMAT
MSb
“S”: Sign Bit(s), “X”: Reserved
MSb
“S”: Sign Bit(s), “X”: Reserved
MSb
“S”: Sign Bit(s)
S
S
S
2
2
2
14
9
9
MSB—ADDRESS 0Ch
MSB—ADDRESS 0Ah
MSB—ADDRESS 0Eh
2
2
2
13
8
8
2
2
2
12
7
7
2
IN
2
2
11
) are measured using the same ADC. Therefore, measurements are a 220ms average updated
6
6
SNS
2
2
2
10
. The voltage-sense range between SNS and V
5
5
2
2
2
4
4
9
LSb
LSb
LSb
IN
2
2
2
3
3
8
17 of 43
pin with respect to V
MSb
MSb
MSb
2
2
2
2
2
7
2
2
2
1
1
6
LSB—ADDRESS 0Dh
LSB—ADDRESS 0Bh
LSB—ADDRESS 0Fh
SS
2
2
2
. Measurements have a 0 to 4.6V range
0
0
5
2
X
X
4
2
X
X
3
Units: 1.5625V/R
SS
2
X
X
2
is ±51.2mV. The input
Units: 4.886mV
Units: 0.125C
2
X
X
1
LSb
LSb
LSb
2
X
X
SNS
0