LTC4006 Linear Technology, LTC4006 Datasheet - Page 5

• Manufacturer Part Number: LTC4006
• Description: Standalone Li-Ion Battery Charger
• Manufacturer: Linear Technology

PI FU CTIO S
NTC (Pin 6): A thermistor network is connected from NTC
to GND. This pin determines if the battery temperature is
safe for charging. The charger and timer are suspended if
the thermistor indicates a temperature that is unsafe for
charging. The thermistor function may be disabled with a
300k to 500k resistor from DCIN to NTC.
I
Mode PWM. Higher I
charging current in normal operation. A 6.04k resistor, in
series with a capacitor of at least 0.1 F to GND, provides
loop compensation. Typical full-scale output current is
40 A. Nominal voltage range for this pin is 0V to 3V.
I
this pin provides a linear indication of charging current.
Peak current is equivalent to 1.19V. Zero current is ap-
proximately 0.309V. A capacitor from I
required to filter higher frequency components. If V
2.5V/cell, then I
battery.
CSP (Pin 9): Current Amplifier CA1 Input. This pin and the
BAT pin measure the voltage across the sense resistor,
R
quired for both peak and average current mode operation.
TEST CIRCUIT
TH
MON
SENSE
U
(Pin 7): Control Signal of the Inner Loop of the Current
(Pin 8): Current Monitoring Output. The voltage at
, to provide the instantaneous current signals re-
U
MON
= 1.19V when conditioning a depleted
U
TH
voltage corresponds to higher
35mV
MON
+
–
to ground is
10
BAT
11.67 A
3k
BAT
<
BAT (Pin 10): Battery Sense Input and the Negative
Reference for the Current Sense Resistor. A precision
internal resistor divider sets the final float potential on this
pin. The resistor divider is disconnected during shutdown.
CLP (Pin 11): Positive Input to the Supply Current Limiting
Amplifier, CL1. The threshold is set at 100mV above the
voltage at the CLN pin. When used to limit supply current,
a filter is needed to filter out the switching noise. If no
current limit function is desired, connect this pin to CLN.
CLN (Pin 12): Negative Reference for the Input Current
Limit Amplifier, CL1. This pin also serves as the power
supply for the IC. A 10 F to 22 F bypass capacitor should
be connected as close as possible to this pin.
TGATE (Pin 13): Drives the top external P-channel MOSFET
of the battery charger buck converter.
PGND (Pin 14): High Current Ground Return for the BGATE
Driver.
BGATE (Pin 15): Drives the bottom external N-channel
MOSFET of the battery charger buck converter.
INFET (Pin 16): Drives the Gate of the External Input PFET.
V
REF
+
–
EA
LT1055
+
–
LTC4006
7
4006 TC
I
TH
0.6V
LTC4006
sn4006 4006is
5