FAN5400_11 Datasheet, PDF (4/37 Pages) Fairchild Semiconductor – FAN5400 / FAN5401 / FAN5402 / FAN5403 / FAN5404 / FAN5405 USB-Compliant Single-Cell Li-Ion Switching Charger

Pin Configuration
A1
A2
A3
A4
A4
A3
A2
A1
B1
B2
B3
B4
B4
B3
B2
B1
C1
C2
C3
C4
C4
C3
C2
C1
D1
D2
D3
D4
D4
D3
D2
D1
E1
E2
E3
E4
E4
E3
E2
E1
Top View
Figure 4. WLCSP-20 Pin Assignments
Bottom View
Pin Definitions
Pin #
A1, A2
A3
A4
B1-B3
B4
C1-C3
C4
D1-D3
D4
E1
E2
E2
E3
E4
Name Part # Description
VBUS
ALL
Charger Input Voltage and USB-OTG output voltage. Bypass with a 1F capacitor to
PGND.
NC
ALL
No Connect. No external connection is made between this pin and the IC’s internal
circuitry.
SCL
ALL I²C Interface Serial Clock. This pin should not be left floating.
PMID
Power Input Voltage. Power input to the charger regulator, bypass point for the input
ALL current sense, and high-voltage input switch. Bypass with a minimum of 4.7F, 6.3V
capacitor to PGND.
SDA
ALL I²C Interface Serial Data. This pin should not be left floating.
SW
ALL Switching Node. Connect to output inductor.
STAT
ALL
Status. Open-drain output indicating charge status. The IC pulls this pin LOW when charge
is in process.
PGND
OTG
ALL
Power Ground. Power return for gate drive and power transistors. The connection from this
pin to the bottom of C_MID should be as short as possible.
On-The-Go. Enables boost regulator in conjunction with OTG_EN and OTG_PL bits (see
ALL Table 16). On VBUS Power-On Reset (POR), this pin sets the input current limit for t15MIN
charging.
CSIN
ALL
Current-Sense Input. Connect to the sense resistor in series with the battery. The IC uses
this node to sense current into the battery. Bypass this pin with a 0.1F capacitor to PGND.
AUXPWR
FAN5400,
FAN5401,
FAN5402
Auxiliary Power. Connect to the battery pack to provide IC power during High-Impedance
Mode. Bypass with a 1F capacitor to PGND.
FAN5403, Charge Disable. If this pin is HIGH, charging is disabled. When LOW, charging is
DISABLE FAN5404, controlled by the I²C registers. When this pin is HIGH, the 15-minute timer is reset. This pin
FAN5405 does not affect the 32-second timer.
VREG
Regulator Output. Connect to a 1F capacitor to PGND. This pin can supply up to 2mA of
ALL DC load current. For FAN5400-FAN5402, the output voltage is PMID, which is limited to
6.5V. For FAN5403-FAN5405, the output voltage is regulated to 1.8V.
VBAT
ALL
Battery Voltage. Connect to the positive (+) terminal of the battery pack. Bypass with a
0.1F capacitor to PGND if the battery is connected through long leads.
© 2009 Fairchild Semiconductor Corporation
FAN5400 Family • Rev. 1.0.7
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