MAX8601ETD+T Maxim Integrated Products, MAX8601ETD+T Datasheet - Page 8

• Manufacturer Part Number: MAX8601ETD+T
• Description: IC CHARGER LI+ DUAL 14-TDFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX8601ETD+T

• Function: Charge Management
• Battery Type: Lithium-Ion (Li-Ion)
• Voltage - Supply: 4.15 V ~ 7 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 14-WFDFN Exposed Pad
• Product: Charge Management
• Operating Supply Voltage: 4.15 V to 7 V
• Supply Current: 750 uA
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Charge Safety Timers: Yes
• Mounting Style: SMD/SMT
• Temperature Monitoring: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Single-/Dual-Input 1-Cell Li+ Chargers with
OVP Protection and Programmable Charge Timer
The maximum charging current from a supply connect-
ed to DC is programmed by an external resistor (R
connected from SETI to GND. Calculate the R
as follows:
where I
SETI can also be used to monitor the actual charge-
current level. The output voltage at SETI is proportional
to the charging current as follows:
Note that the prequal current for both USB and DC
input operation is 1/10 of the fast-charge current set by
R
both USB and DC input operation is set to 7.5% of the
fast-charge current set by R
The MAX8600/MAX8601 contain timers for prequal,
fast-charge, and top-off operation. These time periods
are determined by the capacitance from CT to GND. To
set the charge times, calculate C
Note that when charging at 100mA from the USB input
(MAX8601), the fast-charge timer is inhibited. When THM
halts charging, the timers stop and hold their value.
The MAX8600/MAX8601 monitor battery temperature
through a negative TC thermistor which is in close ther-
mal contact with the battery. Select a thermistor resis-
tance that is 10kΩ at +25°C and has a beta of 3500.
The IC compares the resistance from THM to GND and
suspends charging when it is greater than 28.3kΩ or
Table 1. Fault Temperatures for Different Thermistors
8
Resistance at +25°C
Resistance at +50°C
Resistance at 0°C
Nominal Hot Trip Temperature
Nominal Cold Trip Temperature
SETI
_______________________________________________________________________________________
T
T
FASTCHARGE
PREQUAL
. Also, the top-off charge-current threshold for
CHARGE(MAX)
V
THERMISTOR BETA
SETI
R
SETI
= T
I
I
PREQUAL
TOP-OFF
= (I
Battery Temperature Control
TOPOFF
= 334min x (C
= 1500 / I
CHARGE
Timer Capacitor Selection
is in amps and R
Charge Current Selection
= 112.5 / R
= 34.8min x (C
= 150 / R
SETI
CHARGE(MAX)
x R
.
SETI
CT
CT
SETI
as follows:
/ 0.068µF)
) / 1000
SETI
SETI
CT
/ 0.068µF)
is in ohms.
SETI
25,140.55Ω
4587.78Ω
+55.14°C
10,000Ω
-3.24°C
3000
value
SETI
)
less than 3.94kΩ, which translates to a temperature of
0°C to +50°C. Table 1 shows the nominal temperature
limits that result from a wide range of available thermis-
tor temperature curves. The curves are defined by the
following equation:
where β is the BETA term in Table 1.
Connect THM to GND to disable the temperature-con-
trol function. When R
pause and hold their value.
Connect a 2.2µF ceramic capacitor from BAT to GND
for proper stability. Connect a 1µF ceramic capacitor
from DC to GND. If using the USB input for the
MAX8601, bypass USB to GND with a 1µF ceramic
capacitor. Use a larger input bypass capacitor for high
charging currents to reduce supply noise. All capaci-
tors should be X5R dielectric or better. Be aware that
some capacitors have large voltage coefficients and
should be avoided.
The MAX8600/MAX8601 are in a thermally enhanced
TDFN package with an exposed paddle. Connect the
exposed paddle of the package to a large copper
ground plane to provide a thermal contact between the
device and the circuit board. The exposed paddle
transfers heat away from the device, allowing the IC to
charge the battery with maximum current, while mini-
mizing the increase in die temperature. Note that the
MAX8600/MAX8601s’ thermal-limit control allows the
charger to be tolerant of thermally restricted PC board
layouts that are sometimes unavoidable in compact
portable designs. With such non-optimal layouts, the
charger still operates, but may reduce charge current
to manage temperature rise.
27,148.09Ω
4299.35Ω
+52.60°C
10,000Ω
-1.26°C
3250
R
T
=
R
25
° ×
C
e
THM
⎧
⎪
⎨
⎩ ⎪
β
29,315.94Ω
4029.06Ω
+50.46°C
⎡
⎢
⎣
10,000Ω
+0.46°C
Thermal Considerations
⎛
⎜
⎝
3500
T
disables charging, all timers
+
1
273
Capacitor Selection
⎞
⎟
⎠
−
⎛
⎜
⎝
298
1
31,656.90Ω
⎞
⎟
⎠
3775.75Ω
+48.63°C
⎤
⎥
⎦
10,000Ω
+1.97°C
⎫
⎪
⎬
⎭ ⎪
3750