LTC1735 datasheet(9/16 Pages) LINER

Part #	LTC1735

Description	UV, OV and Reverse Supply Protection Controller Low Operating Current: 125關A

Download	16 Pages

Scroll/Zoom	100%

Manufacturer	LINER [Linear Technology]

Direct Link	http://www.linear.com

Logo

9 / 16 page

LTC4365

9

4365f

Overvoltage and Undervoltage Protection

The LTC4365 provides two accurate comparators to moni-

tor for overvoltage (OV) and undervoltage (UV) conditions

at VIN. If the input supply rises above the user adjustable

OV threshold, the gate of the external MOSFET is quickly

turned off, thus disconnecting the load from the input.

Similarly, if the input supply falls below the user adjust-

able UV threshold, the gate of the external MOSFET also

is quickly turned off. Figure 3 shows a UV/OV application

for an input supply of 12V.

Figure 2. Gate Drive (GATE – VOUT) vs VOUT

APPLICATIONS INFORMATION

Figure 2 highlights the dependence of the gate drive on VIN

and VOUT. When system power is first turned on (SHDN

low to high, VOUT = 0V), gate drive is at a maximum for all

values of VIN. This helps prevent start-up problems into

heavy loads by ensuring that there is enough gate drive

to support the load.

As VOUT ramps up from 0V, the absolute value of the GATE

voltage remains fixed until VOUT is greater than the lower

of (VIN –1V) or 6V. Once VOUT crosses this threshold,

gate drive begins to increase up to a maximum of 9.8V

(for VIN ≥ 12V). The curves of Figure 2 were taken with

a GATE load of –1μA. If there were no load on GATE, the

gate drive for each VIN would be slightly higher.

Note that when VIN is at the lower end of the operating

range, the external N-channel MOSFET must be selected

with a corresponding lower threshold voltage.

VIN

12V

UVTH = 3.5V

OVTH = 18V

4365 F03

DISCHARGE GATE

WITH 50mA SINK

LTC4365

OV

COMPARATOR

UV

COMPARATOR

R3

1820k

UV

0.5V

OV

R2

243k

R1

59k

–

+

25mV

Figure 3. UV, OV Comparators Monitor 12V Supply

The external resistive divider allows the user to select

an input supply range that is compatible with the load at

VOUT. Furthermore, the UV and OV inputs have very low

leakage currents (typically < 1nA at 100°C), allowing for

large values in the external resistive divider. In the applica-

tion of Figure 3, the load is connected to the supply only if

VIN lies between 3.5V and 18V. In the event that VIN goes

above 18V or below 3.5V, the gate of the external N-channel

MOSFET is immediately discharged with a 50mA current

sink, thus isolating the load from the supply.

Table 1 lists some external MOSFETs compatible with

different VIN supply voltages.

Table 1. Dual MOSFETs for Various Supply Ranges

VIN

MOSFET

VTH(MAX)

VGS(MAX)

VDS(MAX)

2.5V

SiB914

0.8V

5V

8V

3.3V

Si5920

1.0V

5V

8V

5V

Si7940

1.5V

8V

12V

≤30V

Si4230

3.0V

20V

30V

≤60V

Si9945

3.0V

20V

60V

VOUT (V)

0

2

4

6

10

8

12

9

15

4365 F02

36

12

VIN = 30V

VIN = 12V

VIN = 5V

VIN = 3.3V

VIN = 2.5V

T = 25°C

IGATE = –1μA

Similar Part No. - LTC1735

Manufacturer	Part #	Datasheet	Description
Linear Technology	LTC1735	373Kb / 32P	High Efficiency Synchronous Step-Down Switching Regulator
	LTC1735	312Kb / 26P	Dual, 2-Phase Step-Down Switching Controller Programmable Soft-Start
	LTC1735	205Kb / 24P	High Voltage, Current Mode Switching Regulator Controller with Programmable Operating Frequency
	LTC1735	379Kb / 32P	High Efficiency Synchronous Step-Down Switching Regulator
	LTC1735	254Kb / 24P	Wide Operating Range, No RSENSE Step-Down Controller

More results

Similar Description - LTC1735

Manufacturer	Part #	Datasheet	Description
Analog Devices	LTC4368	1Mb / 22P	100V UV/OV and Reverse Protection Controller with Bidirectional Circuit Breaker
Linear Technology	LTC4368	283Kb / 6P	100V UV/OV and Reverse Protection Controller with Bidirectional Circuit Breaker
Maxim Integrated Produc...	MAX17612A	585Kb / 21P	4.5V to 60V, 250mA Current-Limiter with OV, UV, and Reverse Protection 19-100363; Rev 0; 6/18
	MAX17613A	827Kb / 28P	4.5V to 60V, 3A Current-Limiter with OV, UV and Reverse Protection Rev 0; 2/19
	MAX17608	619Kb / 21P	4.5V to 60V, 1A Current Limiter with OV, UV, and Reverse Protection Rev 1; 6/18
	MAX17612AEVKIT	785Kb / 9P	MAX17612A 4.5V to 60V, 250mA, Current-Limiter with OV, UV, and Reverse Protection Rev 1; 8/18
	MAX17613AEVKIT	699Kb / 12P	MAX17613A - 4.5V to 60V, 3A Current-Limiter with OV, UV and Reverse Protection Rev 0; 4/19
	MAX17526A	772Kb / 27P	5.5V to 60V, 6A Current-Limiter with OV, UV, Reverse Protection, and Power Limit Rev 1; 11/18
	MAX17526A	994Kb / 27P	5.5V to 60V, 6A Current-Limiter with OV, UV, Reverse Protection, and Power Limit 2021
	MAX17526AEVKIT	960Kb / 12P	MAX17526A ??5.5V to 60V, 6A Current Limiter with OV, UV, Reverse Protection, and Power Limit Rev 0; 6/18

More results

LTC1735 Datasheet(PDF) 9 Page - Linear Technology

LTC1735 Datasheet(HTML) 9 Page - Linear Technology

Similar Part No. - LTC1735

Similar Description - LTC1735

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Datasheet Download

Link URL