MAX8934GETI+ Maxim Integrated Products, MAX8934GETI+ Datasheet - Page 17

• Manufacturer Part Number: MAX8934GETI+
• Description: IC LI BATT CHARGER DUAL 28TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX8934GETI+

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table 1. External Components List for Figures 2 and 3
The MAX8934G is a dual-input linear charger with Smart
Power Selector that safely charges a single Li+/Li-Poly cell
in accordance with JEITA specifications. The MAX8934G
integrates power MOSFETs and control circuitry to manage
power flow in portable devices. See Figure 1. The charger
has two power inputs, DC and USB. These can be sepa-
rately connected to an AC adapter output and a USB port,
or the DC input could be a single power input that connects
to either an adapter or USB. Logic inputs, PEN1 and PEN2,
select the correct current limits for two-input or single-input
operation. Figure 2 is the typical application circuit using
separate DC and USB connectors. Figure 3 is the typical
application circuit using a 5-pin USB connector or another
DC/USB common connector.
In addition to charging the battery, the MAX8934G also
supplies power to the system through the SYS output. The
charging current is also provided from SYS so that the set
input current limit controls the total SYS current, where total
SYS current is the sum of the system load current and the
battery-charging current. SYS is powered from either the
DC input pin or the USB input pin. If both the DC and USB
sources are connected, DC takes precedence.
(Figures 2 and 3)
Dual-Input Linear Charger, Smart Power Selector
COMPONENT
with Advanced Battery Temperature Monitoring
R
R
C
R
C
PU
THMSW
C
R
C
THM
C
C
C
BATT
PSET
ISET
USB
LDO
SYS
DC
CT
VL
(x5)
______________________________________________________________________________________
Detailed Description
DC input current-limit programming resistor
Fast-charge current programming resistor
SYS output bypass capacitors
Logic-output pullup resistors
Battery bypass capacitor
Charger timing capacitor
Negative TC thermistor
LDO output capacitor
THM pullup resistor
USB filter capacitor
DC filter capacitor
V
L
FUNCTION
filter capacitor
In some instances, there may not be enough adapter
current or USB current to supply peak system loads. The
MAX8934G Smart Power Selector circuitry offers flexible
power distribution from an AC adapter or USB source to
the battery and system load. The battery is charged with
any available power not used by the system load. If a
system load peak exceeds the input current limit, supple-
mental current is taken from the battery. Thermal limiting
prevents overheating by reducing power drawn from the
input source.
The MAX8934G features an overvoltage limiter at SYS. If
the DC or USB input voltage exceeds the SYS regulation
voltage, V
at its regulation voltage. The MAX8934G has numerous
other charging and power-management features that are
detailed in the following sections.
A 3.3V ultra-low quiescent current, always-on LDO pro-
vides up to 30mA for indicator LEDs and for backup
power to the system. This LDO powers the thermistor
monitor circuitry and provides bias to the external pullup
resistor for the thermistor.
10FF ±10%, 16V X5R ceramic capacitor (0805)
Taiyo Yuden EMK212BJ106KG
4.7FF ±10%, 10V X5R ceramic capacitor (0805)
Taiyo Yuden LMK212BJ475KD
0.1FF ±10%, 10V X5R ceramic capacitor (0402)
Taiyo Yuden LMK105BJ104KV
10FF ±10%, 6.3V X5R ceramic capacitor (0805)
Taiyo Yuden JMK212BJ106KD
4.7FF ±10%, 6.3V X5R ceramic capacitor (0805)
Taiyo Yuden JMK212BJ475KD
0.068FF ±10%, 16V X5R ceramic capacitor (0402)
Taiyo Yuden EMK105BJ683KV
1FF ±10%, 6.3V X5R ceramic capacitor (0402)
Taiyo Yuden JMK105BJ105KV
1MI ±5% resistor
Vishay NTC Thermistor P/N NTHS0603N01N1003FF
100kI
1.5kI ±1% for 2A limit
3kI ±1% for 1A charging
SYS
does not follow V
PART NUMBER
DC
or V
USB
, but remains
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