Datasheet LT3010, LT3010-5 (Analog Devices) - 8

LT3010/LT3010-5
PIN FUNCTIONS OUT (Pin 1):
Output. The output supplies power to the load. in the Typical Performance Characteristics). The ADJ pin A minimum output capacitor of 1µF is required to prevent voltage is 1.275V referenced to ground, and the output oscillations. Larger output capacitors will be required for voltage range is 1.275V to 60V. applications with large transient loads to limit peak volt-
NC (Pins 3, 6, 7):
No Connection. May be floated, tied to age transients. See the Applications Information section IN or tied to GND. for more information on output capacitance and reverse output characteristics.
GND (Pin 4, Pin 9):
Ground. The exposed backside (pin 9) of the package is an electrical connection for GND. As
SENSE (Pin 2):
Sense. For the LT3010-5, the SENSE pin such, to ensure optimum device operation, pin 9 must be is the input to the error amplifier. Optimum regulation will connected directly to pin 4 on the PC board. be obtained at the point where the SENSE pin is connected to the OUT pin of the regulator. In critical applications,
SHDN (Pin 5):
Shutdown. The SHDN pin is used to put small voltage drops are caused by the resistance (RP) of the LT3010 into a low power shutdown state. The output PC traces between the regulator and the load. These may will be off when the SHDN pin is pulled low. The SHDN be eliminated by connecting the SENSE pin to the output pin can be driven either by 5V logic or open-collector logic at the load as shown in Figure 1 (Kelvin Sense Connec- with a pull-up resistor. The pull-up resistor is only required tion). Note that the voltage drop across the external PC to supply the pull-up current of the open-collector gate, traces will add to the dropout voltage of the regulator. normally several microamperes. If unused, the SHDN pin The SENSE pin bias current is 10µA at the nominal rated must be tied to a logic high or VIN. output voltage.
IN (Pin 8):
Input. Power is supplied to the device through
ADJ (Pin 2):
Adjust. For the adjustable LT3010, this is the the IN pin. A bypass capacitor is required on this pin if input to the error amplifier. This pin is internally clamped the device is more than six inches away from the main to ±7V. It has a bias current of 50nA which flows into the input filter capacitor. In general, the output impedance of pin (see curve of ADJ Pin Bias Current vs Temperature a battery rises with frequency, so it is advisable to include a bypass capacitor in battery-powered circuits. A bypass 8 1 RP capacitor in the range of 1µF to 10µF is sufficient. The IN OUT LT3010 is designed to withstand reverse voltages on the IN LT3010 + 5 2 + SHDN SENSE pin with respect to ground and the OUT pin. In the case of VIN LOAD GND a reversed input, which can happen if a battery is plugged 4, 9 in backwards, the LT3010 will act as if there is a diode in 30105 F01 series with its input. There will be no reverse current flow
Figure 1. Kelvin Sense Connection
into the LT3010 and no reverse voltage will appear at the load. The device will protect both itself and the load. 30105fe 8 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Applications Information Typical Applications Package Description Revision History Typical Application Related Parts