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PIN DESCRIPTION |
| Mnemonic |
Function |
| VSENSE |
Battery Voltage Sense Input. |
| VCS |
Current Sense Input. |
| VREF |
Reference Output. Nominally 2.0 V. |
| COMP |
External Compensation Pin. |
| OUT |
Optocoupler Current Output Drive. |
| VCTRL |
DC Control Input to Set Current Limit, 0 V to 1.2 V. |
| VCC |
Positive Supply. |
| GND |
Ground Pin. |
The ADP3810 and ADP3811 combine a programmable current limit with a battery voltage limit to provide a constant current, constant voltage battery charger controller. In secondary side, off-line applications, the output directly drives the diode side of an optocoupler to give isolated feedback control of a primary side PWM. The circuitry includes two gain (gm) stages, a precision 2.0 V reference, a control input buffer, an Undervoltage Lock Out (UVLO) comparator, an output buffer and an overvoltage comparator.
The current limit amplifier senses the voltage drop across an external sense resistor to control the average current for charging a battery. The voltage drop can be adjusted from 25 mV
to 300 mV, giving a charging current limit from 100 mA to 1.2 amps with a 0.25 sense resistor. An external dc voltage on the VCTRL input sets the voltage drop. Because this input
is high impedance, a filtered PWM output can be used to set the voltage.
As the battery voltage approaches its voltage limit, the voltage sense amplifier takes over to maintain a constant battery voltage. The two amplifiers essentially operate in an "OR" fashion. Either the current is limited, or the voltage is limited.
The ADP3810 has internal thin-film resistors that are trimmed to provide a precise final voltage for LiIon batteries. Four voltage options are available, corresponding to 1-4 LiIon cells as
follows: 4.2 V, 8.4 V, 12.6 V and 16.8 V.
The ADP3811 omits these resistors allowing any battery voltage to be programmed with external resistors.
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Battery Charger Controller for: LiIon Batteries (ADP3810) NiCad, NiMH Batteries (ADP3811)
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Programmable Charge CurrentHigh Precision Battery Voltage LimitPrecision 2.000 V ReferenceLow Voltage Drop Current Sense: 300 mV Full ScaleFull Operation in Shorted and Open Battery ConditionsDrives Diode-Side of OptocouplerWide Operating Supply Range: 2.7 V to 16 VUndervoltage LockoutSO-8 PackageADP3810 Internal Precision Voltage Divider for Battery Sense Four Final Battery Voltage Options Available: 4.2 V, 8.4 V, 12.6 V, 16.8 VADP3811 Adjustable Final Battery Voltage
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Supply Voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.4 V to 18 V
VCTRL, VCS Input Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.4 V to VCC
VSENSE Input Range (ADP3811) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.4 V to VCC
VSENSE Input Range (ADP3810) . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.4 V to 20 V
Maximum Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500 mW
Operating Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . 40°C to +85°C
Storage Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65°C to 150°C
Lead Temperature (Soldering, 10 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . . +300°C
Post a Buying Lead
Required Field 
