MAX17040G+T Maxim Integrated Products, MAX17040G+T Datasheet - Page 5

• Manufacturer Part Number: MAX17040G+T
• Description: IC 2-WIRE FG W/MODEL GAUGE
• Manufacturer: Maxim Integrated Products
• Series: ModelGauge™r

Specifications of MAX17040G+T

• Function: Fuel, Gas Gauge/Monitor
• Battery Type: Lithium-Ion (Li-Ion)
• Voltage - Supply: 2.5 V ~ 4.5 V
• Operating Temperature: -20°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 8-TDFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 90-2771G+TRL

Figure 1. 2-Wire Bus Timing Diagram
Figure 2. Block Diagram
UCSP
A1
A2
A3
B1
B2
B3
C1
C2
C3
—
SDA
SCL
CELL
GND
V
t
F
DD
PIN
S
TDFN
—
—
8
7
1
6
2
5
3
4
ADC (VCELL)
REFERENCE
VOLTAGE
BIAS
_______________________________________________________________________________________
t
LOW
t
GROUND
HD:STA
NAME
CELL
GND
SDA
CTG
N.C.
SCL
SEO
IC
V
Compact, Low-Cost 1S/2S Fuel Gauges
EO
EP
DD
MAX17040
MAX17041
t
R
Serial Data Input/Output. Open-drain 2-wire data line. Connect this pin to the DATA signal of the
2-wire interface. This pin has a 0.2µA typical pulldown to sense disconnection.
Serial Clock Input. Input only 2-wire clock line. Connect this pin to the CLOCK signal of the
2-wire interface. This pin has a 0.2µA typical pulldown to sense disconnection.
Connect to Ground. Connect to VSS during normal operation.
External 32kHz Clocking Signal. Input for external clocking signal to be the primary system
clock. Configured to implement interrupt feature with a pulldown set on SEO pin.
No Connect. Do not connect.
Battery-Voltage Input. The voltage of the cell pack is measured through this pin.
External 32kHz Clocking Signal Enable Input. Input to enable external clocking signal on EO pin
with a pullup state; a pulldown state to configure the interrupt feature. External 32kHz clock
enable. Connects logic-low to enable external interrupt.
Power-Supply Input. 2.5V to 4.5V input range. Connect to system power through a decoupling
network. Connect a 10nF typical decoupling capacitor close to pin.
Ground. Connect to the negative power rail of the system.
Exposed Pad (TDFN Only). Connect to ground.
t
HD:DAT
(SOC, RATE)
INTERFACE
TIME BASE
MACHINE
t
(32kHz)
2-WIRE
SU:DAT
STATE
EO
SEO
CTG
SDA
SCL
t
F
t
SU:STA
Figure 1 shows the 2-wire bus timing diagram, and
Figure 2 is the MAX17040/MAX17041 block diagram.
The MAX17040/MAX17041 use a sophisticated battery
model, which determines the SOC of a nonlinear Li+
battery. The model effectively simulates the internal
dynamics of a Li+ battery and determines the SOC. The
model considers the time effects of a battery caused by
the chemical reactions and impedance in the battery.
The MAX17040/MAX17041 SOC calculation does not
accumulate error with time. This is advantageous
Sr
ModelGauge Theory of Operation
FUNCTION
t
HD:STA
Detailed Description
t
SU:STO
t
SP
t
Pin Description
R
P
t
BUF
S
5