Data Sheet

LT4322

analog.com

Rev. 0

7 of 29

always between 9V and 14V with respect to VSSA and connect a 1µF or larger ceramic

bypass capacitor from VDDA to VSSA.

Pin 5

VDDC

Input Supply to LDO. This is the input supply voltage to the LDO. It replenishes the

external VDDA hold-up capacitor when the VDDC voltage is higher than the VDDA voltage.

Connect to the drain of the external MOSFET for VDDCto VSSA voltages less than or equal

to 60V. For higher VDDC voltages, an external high-voltage depletion MOSFET is

required. See the Operation at Voltages Above 60V section for details. If VDDA is powered

directly with a DC power supply, connect VDDC to VSSA.

Pin 8

CATHODE

External MOSFET Drain Voltage Kelvin Sense Input. CATHODE is the sense pin

connection to the CATHODE end of the ideal diode circuit. The voltage sensed at this

pin with respect to ANODE is used to control the MOSFET gate for forward voltage

regulation and reverse current turn-off. Connect to the drain of the N-Channel power

MOSFET for CATHODE to VSSA voltages less than or equal to 60V. For higher CATHODE

voltages, an external high-voltage MOSFET is required. See the Operation at Voltages

Above 60V section for details.

TYPICAL PERFORMANCE CHARACTERISTICS

TA = 25°C, unless otherwise noted.

Figure 5. VDDA Input Supply Current vs. Temperature

Figure 6. VDDA LDO Start-Up and Gulp Current vs.

Temperature

VCATHODE – m

VCATHODE = 24V

VDDA = 12V, VDDC = 0V

TEMPERATURE (°C)

– 0

–

0

25

50

75

100

125

150

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

ISTART

IGULP

TEMPERATURE (°C)

– 0

–

0

25

50

75

100

125

150

0

10

20

30

40

50