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LTC1154 High-Side Micropower MOSFET Driver
FEATURES
s s s s s s s s s
DESCRIPTIO
Fully Enhances N-Channel Power MOSFETs 8A IQ Standby Current 85A IQ ON Current No External Charge Pump Capacitors 4.5V to 18V Supply Range Short-Circuit Protection Thermal Shutdown via PTC Thermistor Status Output Indicates Shutdown Available in 8-Pin SOIC
The LTC1154 single high-side gate driver allows using low cost N-channel FETs for high-side switching applications. An internal charge pump boosts the gate drive voltage above the positive rail, fully enhancing an N-channel MOS switch with no external components. Micropower operation, with 8A standby current and 85A operating current, allows use in virtually all systems with maximum efficiency. Included on chip is programmable over-current sensing. A time delay can be added to prevent false triggering on high in-rush current loads. An active high shutdown input is also provided and interfaces directly to a standard PTC thermistor for thermal shutdown. An open-drain output is provided to report switch status to the P. An active low enable input is provided to control multiple switches in banks. The LTC1154 is available in both 8-pin DIP and 8-pin SOIC packages.
APPLICATI
s s s s s s
S
Laptop Computer Power Switching SCSI Termination Power Switching Cellular Telephone Power Management Battery Charging and Management High-Side Industrial and Automotive Switching Stepper Motor and DC Motor Control
TYPICAL APPLICATI
Ultra-Low Voltage Drop High-Side Switch with Short-Circuit Protection
5V 51k IN P EN LTC1154 STATUS GND G SD IRLR024 VS 200k** DS
SUPPLY CURRENT (A)
50
0.036* 0.1F**
2.7A MAX
45 40 35 30 25 20 15 10 5
5V LOAD
ALL COMPONENTS SHOWN ARE SURFACE MOUNT. * IMS026 INTERNATIONAL MANUFACTURING SERVICE, INC. (401) 683-9700 ** NOT REQUIRED IF LOAD IS RESISTIVE OR INDUCTIVE.
LTC1154 * TA01
0 0 5 10 15 SUPPLY VOLTAGE (V) 20
LTC1153 * TA02
U
Standby Supply Current
VIN = 0V TJ = 25C
UO
UO
1
LTC1154 ABSOLUTE AXI U RATI GS
Current (Any Pin).................................................. 50mA Operating Temperature LTC1154C .............................................. 0C to 70C Storage Temperature Range ................. - 65c to 150C Lead Temperature (Soldering, 10 sec.)................ 300C
Supply Voltage ........................................................ 22V Input Voltage ..................... (VS + 0.3V) to (GND - 0.3V) Enable Input Voltage .......... (VS + 0.3V) to (GND - 0.3V) Gate Voltage ....................... (VS + 24V) to (GND - 0.3V) Status Output Voltage .............................................. 15V
PACKAGE/ORDER I FOR ATIO
TOP VIEW IN 1 ENABLE 2 STATUS 3 GND 4 8 7 6 5 VS DRAIN SENSE GATE SHUTDOWN
ORDER PART NUMBER LTC1154CN8
N8 PACKAGE 8-LEAD PLASTIC DIP
LTC1154 * PO01
TJMAX = 100C, JA = 130C/W (N8)
ELECTRICAL CHARACTERISTICS VS = 4.5V to 18V, TA = 25C, VEN = 0V, VSD = 0V unless otherwise noted.
SYMBOL VS IQ IQ IQ VINH VINL IIN CIN VENH VENL IEN VSDH VSDL ISD VSEN ISEN PARAMETER Supply Voltage Quiescent Current OFF Quiescent Current ON Quiescent Current ON Input High Voltage Input Low Voltage Input Current Input Capacitance ENABLE Input High Voltage ENABLE Input Low Voltage ENABLE Input Current Shutdown Input High Voltage Shutdown Input Low Voltage Shutdown Input Current Drain Sense Threshold Voltage
q q q
CONDITIONS
q
VS = 5V, VIN = 0V VS = 5V, VIN = 5V VS = 12V, VIN = 5V
q q
0V < VIN < VS
0V < VIN < VS
0V < VIN < VS
Drain Sense Input Current
0V < VSEN < VS
2
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U
W
WW
U
W
TOP VIEW IN 1 ENABLE 2 STATUS 3 GND 4 8 7 6 5 VS DRAIN SENSE GATE SHUTDOWN
ORDER PART NUMBER LTC1154CS8
S8 PACKAGE 8-LEAD PLASTIC SOIC
LTC1154 * PO02
S8 PART MARKING 1154
TJMAX = 100C, JA = 150C/W
MIN 4.5
LTC1154C TYP 8 85 180
MAX 18.0 20 120 400 0.8 1
UNITS V A A A V V A pF V
2
q
5 3.5 2.6 1.0 2 0.8 1 80 75 100 100 120 125 0.1 0.6 1
V A V V A mV mV A
q q q q
q
LTC1154 ELECTRICAL CHARACTERISTICS VS = 4.5V to 18V, TA = 25C, VEN = 0V, VSD = 0V unless otherwise noted.
SYMBOL PARAMETER CONDITIONS VS = 5V VS = 6V VS = 12V ISTAT = 400A VSTAT = 12V VS = 5V, CGATE = 1000pF Time for VGATE > VS + 2V Time for VGATE > VS + 5V VS = 12V, CGATE = 1000pF Time for VGATE > VS + 5V Time for VGATE > VS + 10V tOFF Turn-OFF Time VS = 5V, CGATE = 1000pF Time for VGATE < 1V VS = 12V, CGATE = 1000pF Time for VGATE < 1V tSC Short-Circuit Turn-OFF Time VS = 5V, CGATE = 1000pF Time for VGATE < 1V VS = 12V, CGATE = 1000pF Time for VGATE < 1V tSD Shutdown Turn-OFF Time VS = 5V, CGATE = 1000pF Time for VGATE < 1V VS = 12V, CGATE = 1000pF Time for VGATE < 1V The q denotes specifications which apply over the operating temperature range.
q q q q q
MIN 6.0 7.5 15.0
LTC1154C TYP 7.0 8.3 18.0 0.05
MAX 9.0 15.0 25.0 0.4 1
UNITS V V V V A s s s s s s s s s s
VGATE - VS Gate Voltage Above Supply
VSTAT ISTAT tON
Status Output Low Voltage Status Output Leakage Current Turn-ON Time
30 100 20 50 10 10 5 5
110 450 80 160 36 28 25 23 17 13
300 1000 200 500 60 60 40 40 40 35
TYPICAL PERFOR A CE CHARACTERISTICS
Standby Supply Current
50 45 40
SUPPLY CURRENT (A)
VIN = 0V TA = 25C
SUPPLY CURRENT (A)
35 30 25 20 15 10 5 0 0 5 10 15 SUPPLY VOLTAGE (V) 20
LTC1154 * TPC01
600 500 400 300 200 100 0 0 5 10 15 SUPPLY VOLTAGE (V) 20
LTC1154 * TPC02
VGATE - VS (V)
UW
Supply Current ON
1000 900 800 700 TA = 25C 24 22 20 18 16 14 12 10 8 6 0
High-Side Gate Voltage
0
5
10 15 SUPPLY VOLTAGE (V)
20
LTC1154 * TPC03
3
LTC1154
TYPICAL PERFOR A CE CHARACTERISTICS
Input Threshold Voltage
2.4 2.2
INPUT THRESHOLD VOLTAGE (V)
DRAIN SENSE THRESHOLD VOLTAGE (V)
2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0 5 10 15 SUPPLY VOLTAGE (V) 20
LTC1154 * TPC04
VON VOFF
100 90 80 70 60 50 0 5 10 15 SUPPLY VOLTAGE (V) 20
LTC1154 * TPC05
VGATE (V)
Turn-ON Time
1000 900 800
TURN-OFF TIME (s) TURN-ON TIME (s)
CGATE = 1000pF
700 600 500 400 300 200 100 0 0 5 10 15 SUPPLY VOLTAGE (V) 20 VGS = 5V
35 30 25 20 15 10 5 0 0 5 10 15 SUPPLY VOLTAGE (V) 20
LTC1154 * TPC08
TURN-OFF TIME (s)
VGS = 2V
Standby Supply Current
50 45 40
SUPPLY CURRENT (A)
1000
800
SUPPLY CURRENT (A)
INPUT THRESHOLD VOLTAGE (V)
VIN = 0V VEN = 0V
35 30 25 20 15 10 5 0 -50 -25 VS = 18V VS = 5V 50 25 0 75 TEMPERATURE (C) 100 125
4
UW
LTC1153 * TPC07
Drain Sense Threshold Voltage
150 140 130 120 110
30 27 24 21 18 15 12 9 6 3 0
Low-Side Gate Voltage
0
2
6 8 4 SUPPLY VOLTAGE (V)
10
LTC1154 * TPC06
Turn-OFF Time
50 45 40 CGATE = 1000pF TIME FOR VGATE < 1V
Short-Circuit Turn-OFF Delay Time
50 45 40 35 30 25 20 15 10 5 0 0 5 10 15 SUPPLY VOLTAGE (V) 20
LTC1154 * TPC09
CGATE = 1000pF TIME FOR VGATE < 1V VSEN = VS - 1V NO EXTERNAL DELAY
Supply Current ON
2.4 VIN = 5V VEN = 0V 2.2 2.0 1.8 1.6 1.4 1.2 1.O 0.8 0.6 100 125 900
Input ON Threshold Voltage
700 600 500 400 300 200 100 VS = 5V VS = 12V
VS = 5V VS = 18V
0 -50 -25
50 25 0 75 TEMPERATURE (C)
0.4 -50 -25
50 25 0 75 TEMPERATURE (C)
100
125
LTC1154 * TPC10
LTC1154 * TPC11
LTC1154 * TPC12
LTC1154
TYPICAL PERFOR A CE CHARACTERISTICS
Shutdown Threshold Voltage
2.4
SHUTDOWN THRESHOLD VOLTAGE (V)
ENABLE THRESHOLD VOLTAGE (V)
2.2 2.0 1.8 1.6 1.4 1.2 1.O 0.8 0.6 0.4 -50 -25 50 25 0 75 TEMPERATURE (C) 100 125 VS = 5V VS = 18V
GATE DRIVE CURRENT (A)
PI FU CTIO S
Input and Shutdown Pins The LTC1154 input pin is active high and activates all of the protection and charge pump circuitry when switched ON. The shutdown pin is designed to immediately disable the switch if a secondary fault condition (over temperature, etc.) is detected. The LTC1154 logic and shutdown inputs are high impedance CMOS gates with ESD protection diodes to ground and supply and therefore should not be forced beyond the power supply rails. The shutdown pin should be connected to ground when not in use. ENABLE Input Pin The ENABLE input can be used to enable a number of LTC1154 high-side switches in banks or to provide a secondary means of control. It can also act as an inverting input. The ENABLE input is a high impedance CMOS gate with ESD clamp diodes to ground and supply and therefore should not be forced beyond the power supply rails. This pin should be grounded when not in use. Gate Drive Pin The gate drive pin is either driven to ground when the switch is turned OFF or driven above the supply rail when the switch is turned ON. This pin is a relatively high impedance when driven above the rail (the equivalent of a few hundred k). Care should be taken to minimize any loading of this pin by parasitic resistance to ground or supply. Supply Pin The supply pin of the LTC1154 serves two vital purposes. The first is obvious: it powers the input, gate drive, regulation and protection circuitry. The second purpose is less obvious: it provides a Kelvin connection to the top of the drain sense resistor for the internal 100mV reference. The LTC1154 is designed to be continuously powered so that the gate of the MOSFET is actively driven at all times. If it is necessary to remove power from the supply pin and then re-apply it, the input pin (or enable pin) should be cycled a few milliseconds after the power is re-applied to reset the input latch and protection circuitry. Also, the input and enable pins should be isolated with 10k resistors to limit the current flowing through the ESD protection diodes to the supply pin.
UW
LTC1154 * TPC13
ENABLE Threshold Voltage
5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 -50 -25 ENABLE 50 25 0 75 TEMPERATURE (C) 100 125
0.1
Gate Drive Current
1000 TA = 25C 100 VS = 18V VS = 12V 10
VS = 12V
DISABLE
1
VS = 5V
0
4 8 12 16 GATE VOLTAGE ABOVE SUPPLY (V)
20
LTC1154 * TPC14
LTC1154 * TPC15
U
U
U
The supply pin of the LTC1154 should never be forced below ground as this may result in permanent damage to the device. A 300 resistor should be inserted in series with the ground pin if negative supply voltage transients are anticipated.
5
LTC1154
PI FU CTIO S
Drain Sense Pin The drain sense pin is compared against the supply pin voltage. If the voltage at this pin is more than 100mV below the supply pin, the input latch will be reset and the MOSFET gate will be quickly discharged. Cycle the input, or ENABLE input, to reset the short-circuit latch and turn the MOSFET back on. This pin is also a high impedance CMOS gate with ESD protection and therefore should not be forced beyond the power supply rails. To defeat the over current protection, short the drain sense to supply. Some loads, such as large supply capacitors, lamps, or motors require high in-rush currents. An RC time delay can be added between the sense resistor and the drain sense pin to ensure that the drain sense circuitry does not false-trigger during start-up. This time constant can be set from a few microseconds to many seconds. However, very long delays may put the MOSFET in risk of being destroyed by a short-circuit condition. (see Applications Information Section). Status Pin The status pin is an open-drain output which is driven low whenever a fault condition is detected. A 51k pull-up resistor should be connected between this output and a logic supply. The status pins of multiple LTC1154s can be OR'd together if independent fault sensing is not required. No connection is required to this pin when not in use.
BLOCK DIAGRA
VS LOW STANDBY CURRENT REGULATOR COMP 100mV REFERENCE 10s DELAY SHUTDOWN TTL-TO-CMOS CONVERTER SHUTDOWN
INPUT
TTL-TO-CMOS CONVERTER
ENABLE
GND
STATUS
6
W
U
U
U
ANALOG SECTION
DRAIN SENSE
GATE CHARGE AND DISCHARGE CONTROL LOGIC ANALOG DIGITAL R VOLTAGE REGULATORS INPUT LATCH ONE SHOT S OSCILLATOR AND CHARGE PUMP FAST/SLOW GATE CHARGE LOGIC
GATE
FAULT DETECTION AND STATUS OUTPUT DRIVER
LTC1154 * BD01
LTC1154 TRUTH TABLE
INPUTS IN X L H H H EN H X L L L SD X X L L OUTPUTS GATE STATUS L L H L L H H H L L SWITCH CONDITION SWITCH OFF SWITCH OFF SWITCH ON SWITCH LATCHED OFF (OVER CURRENT) SWITCH LATCHED OFF (SHUTDOWN)
L = LOGIC LOW H = LOGIC HIGH X = IRRELEVANT
= EDGE TRIGGERED
The Truth Table demonstrates how the LTC1154 receives inputs and returns status information to the P. The ENABLE and input signal from the P controls the switch in its normal operating mode, where the rise and fall time of the gate drive are controlled to limit EMI and RFI emissions. The shutdown and over-current detection circuitry however, switch the gate off at a much higher rate to limit the exposure of the MOSFET switch and the load to dangerous conditions. The status pin remains high as long as the switch is operating normally, and is driven low only when a fault condition is detected. Note that the shutdown pin is edge-sensitive and latches the output off even if the shutdown pin returns to a low state.
LTC1154 OPERATIO
The LTC1154 is a single micropower MOSFET driver with built-in protection, status feedback and gate charge pump. The LTC1154 consists of the following functional blocks: TTL and CMOS Compatible Inputs The LTC1154 input and shutdown input have been designed to accommodate a wide range of logic families. Both input thresholds are set at about 1.3V with approximately 100mV of hysteresis. A low standby current voltage regulator provides continuous bias for the TTL-to-CMOS converter. The TTL-toCMOS converter output enables the rest of the circuitry. In this way the power consumption is kept to a minimum in the standby mode. ENABLE Input The ENABLE input is CMOS compatible and inhibits the input signal whenever it is held logic high. This input should be grounded when not in use. Internal Voltage Regulation The output of the TTL-to-CMOS converter drives two regulated supplies which power the low voltage CMOS logic and analog blocks. The regulator outputs are isolated from each other so that the noise generated by the charge
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pump logic is not coupled into the 100mV reference or the analog comparator. Gate Charge Pump Gate drive for the MOSFET switch is produced by an adaptive charge pump circuit which generates a gate voltage substantially higher than the power supply voltage. The charge pump capacitors are included on chip and therefore no external components are required to generate the gate drive. Drain Current Sense The LTC1154 is configured to sense the current flowing into the drain of the power MOSFET in a high-side application. An internal 100mV reference is compared to the drop across a sense resistor (typically 0.002 to 0.10) in series with the drain lead. If the drop across this resistor exceeds the internal 100mV threshold, the input latch is reset and the gate is quickly discharged via a large N-channel transistor. Controlled Gate Rise and Fall Times When the input is switched ON and OFF, the gate is charged by the internal charge pump and discharged in a controlled manner. The charge and discharge rates have
7
LTC1154
LTC1154 OPERATIO
been set to minimize RFI and EMI emissions in normal operation. If a short-circuit or current overload condition is encountered, the gate is discharged very quickly (typically a few microseconds) by a large N-channel transistor. Status Output Driver The status circuitry continuously monitors the fault detection logic. This open-drain output is driven low when the
APPLICATI
S I FOR ATIO
MOSFET and Load Protection The LTC1154 protects the power MOSFET switch by removing drive from the gate as soon as an over-current condition is detected. Resistive and inductive loads can be protected with no external time delay in series with the drain sense pin. Lamp loads, however, require that the over-current protection by delayed long enough to start the lamp but short enough to ensure the safety of the MOSFET. Resistive Loads Loads that are primarily resistive should be protected with as short a delay as possible to minimize the amount of time that the MOSFET is subjected to an overload condition. The drain sense circuitry has a built-in delay of approximately 10s to eliminate false triggering by power supply or load transient conditions. This delay is sufficient to "mask" short load current transients and the starting of a small capacitor (<1F) in parallel with the load. The drain sense pin can therefore be connected directly to the drain current sense resistor as shown in Figure 1. Inductive Loads Loads that are primarily inductive, such as relays, solenoids and stepper motor windings should be protected with as short a delay as possible to minimize the amount of time that the MOSFET is subjected to an overload condition. The built-in 10s delay will ensure that the overcurrent protection is not false-triggered by a supply or load transient. No external delay components are required as shown in Figure 2. Large inductive loads (>0.1mH) may require diodes connected directly across the inductor to safely divert the
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gate of the MOSFET is driven low by the protection circuitry. The status circuitry is reset along with the input latch when the input, or ENABLE input, is cycled. stored energy to ground. Many inductive loads have these diodes included. If not, a diode of the proper current rating should be connected across the load, as shown in Figure 2, to safely divert the stored energy.
12V IN EN LTC1154 STATUS GND G 15V SD IRFZ24 VS DS
U
UO
+
100F 0.036
CLOAD 1F
RLOAD 12
LTC1154 * F01
Figure 1. Protecting Resistive Loads
12V IN EN LTC1154 STATUS GND G 15V SD IRFZ24 VS DS
+
100F 0.036
1N5400
12V, 1A SOLENOID
LTC1154 * F02
Figure 2. Protecting Inductive Loads
LTC1154
APPLICATI S I FOR ATIO U
Lamp Loads The in-rush current created by a lamp during turn-on can be 10 to 20 times greater than the rated operating current. The circuit shown in Figure 4 shifts the current limit threshold up by a factor of 11:1 (to 30A) for 100ms when the bulb is first turned on. The current limit then drops down to 2.7A after the in-rush current has subsided.
12V
Capacitive Loads Large capacitive loads, such as complex electrical systems with large bypass capacitors, should be powered using the circuit shown in Figure 3. The gate drive to the power MOSFET is passed through an RC delay network, R1 and C1, which greatly reduces the turn-on ramp rate of the switch. And since the MOSFET source voltage follows the gate voltage, the load is powered smoothly and slowly from ground. This dramatically reduces the start-up current flowing into the supply capacitor(s) which, in turn, reduces supply transients and allows for slower activation of sensitive electrical loads. (Diode, D1, provides a direct path for the LTC1154 protection circuitry to quickly discharge the gate in the event of an over-current condition).
12V IN EN LTC1154 STATUS GND G SD C1 0.33F 15V R1 100k VS CD 0.01F DS D1 1N4148 R2 100k MTP3055E OUT RD 100k
+
470F 0.036
Figure 3. Powering Large Capacitive Loads
OVER-CURRENT SHUTDOWN TIME (1 = RC)
The RC network, RD and CD, in series with the drain sense input should be set to trip based on the expected characteristics of the load after start-up. With this circuit, it is possible to power a large capacitive load and still react quickly to an over-current condition. The ramp rate at the output of the switch as it lifts off ground is approximately: dV/dt = (VGATE - VTH)/(R1 x C1) And therefore the current flowing into the capacitor during start-up is approximately: ISTART-UP = CLOAD x dV/dt Using the values shown in Figure 3, the start-up current is less than 100mA and does not false-trigger the drain sense circuitry which is set at 2.7A with a 1ms delay.
W
U
UO
+
470F IN EN LTC1154 STATUS GND G 1M SD 9.1V 12V/1A BULB
LTC1154 * F04
VS DS
10k 100k
0.036
VN2222LL 0.1F MTP3055EL
Figure 4. Lamp Driver with Delayed Protection
Selecting RD and CD Figure 5 is a graph of normalized over-current shutdown time versus normalized MOSFET current. This graph is used to select the two delay components, RD and CD, which make up a simple RC delay between the drain sense resistor and the drain sense input.
10
+
CLOAD 100F
LTC1154 * F03
1
0.1
0.01 1 10 100 MOSFET CURRENT (1 = SET CURRENT)
LTC1154 * F05
Figure 5. Over-Current Shutdown Time vs MOSFET Current
9
LTC1154
APPLICATI
S I FOR ATIO
The Y axis of the graph is normalized to one RC time constant. The X axis is normalized to the current. (The set current is defined as the current required to develop 100mV across the drain sense resistor). Note that the shutdown time is shorter for increasing levels of MOSFET current. This ensures that the total energy dissipated by the MOSFET is always within the bounds established by the manufacturer for safe operation. (See MOSFET data sheet for further information). Using a Speed-Up Diode
To reduce the amount of time that the power MOSFET is in a short-circuit condition, "bypass" the delay resistor with a small signal diode as shown in Figure 6. The diode will engage when the drop across the drain sense resistor exceeds about 0.7V, providing a direct path to the sense pin and dramatically reducing the amount of time the
12V IN EN LTC1154 STATUS GND G 15V SD LOAD IRF530 VS 0.01F DS
+
100F 1N4148 100k 0.036
LTC1154 * F06
Figure 6. Using a Speed-Up Diode
MOSFET is in an overload condition. The drain sense resistor value is selected to limit the maximum DC current to 2.8A. The diode conducts when the drain current exceeds 20A and reduces the turn-off time to 15s. Reverse Battery Protection The LTC1154 can be protected against reverse battery conditions by connecting a resistor in series with the ground lead as shown in Figure 7. The resistor limits the supply current to less than 50mA with - 12V applied.
10
U
12V 5V 120k 10k 5V P OR CONTROL LOGIC
W
U
UO
+
10F IN 10k EN 10k LTC1154 STATUS GND 300 G 15V SD 10k LOAD MTP12N06 DS VS 0.05
LTC1154 * F07
Figure 7. Reverse Battery Protection
Since the LTC1154 draws very little current while in normal operation, the drop across the ground resistor is minimal. The 5V P (or control logic) is protected by the 10k resistors in series with the input and status pins. Current Limited Power Supplies The LTC1154 requires at least 3.5V at the supply pin to ensure proper operation. It is therefore necessary that the supply to the LTC1154 be held higher than 3.5V at all times, even when the output of the switch is short circuited to ground. The output voltage of a current limited regulator may drop very quickly during short circuit and pull the supply pin of the LTC1154 below 3.5V before the shutdown circuitry has had time to respond and remove drive from the gate of the power MOSFET. A supply filter should
>7V
+
100F
5V/2A REGULATOR *20
+
10F 0.1
+
IN EN LTC1154 STATUS GND G SD VS 0.1F DS 47F*
1N4148 100k
IRLR024 SHORT CIRCUIT
*SUPPLY FILTER COMPONENTS
LTC1154 * F08
Figure 8. Supply Filter for Current Limited Supplies
LTC1154
APPLICATI S I FOR ATIO
be added as shown in Figure 8 which holds the supply pin of the LTC1154 high long enough for the over-current shutdown circuitry to respond and fully discharge the gate. Five volt linear regulators with small output capacitors are the most difficult to protect as they can "switch" from a voltage mode to a current limited mode very quickly. The
TYPICAL APPLICATI
5V IN P OR CONTROL LOGIC EN LTC1154 STATUS GND G 6V VS DS
S
High-Side Driver with Over-Voltage Shutdown
5V 100F IN P OR CONTROL LOGIC IRLZ24 30k EN LTC1154 STATUS GND G SD 5V LOAD SWITCH IS SHUTDOWN WHEN VS > 5.7V
LTC1154 * TA03 LTC1154 * TA05
High-Side Driver with Thermal Shutdown +
SD PTC THERMISTOR (100C)* 6V LOAD
*RL3006-50-100-25-PT0 KEYSTONE
A
51k pullup resistor should be connected between Status Output and 5V Logic Supply.
High-Side Driver with Under-Voltage Shutdown
5V
+
100F 1N4148* 10k
+
5V IN P OR CONTROL LOGIC EN LTC1154 STATUS GND G SD 6V LOAD IRLZ24 VS DS 2N2907 1F**
*OPTIONAL IF SUPPLY VOLTAGE LESS THAN 6V. **CAPACITOR CHARGED TO SUPPLY VOLTAGE. SHUTDOWN OCCURS WHEN SUPPLY VOLTAGE DROPS BY 0.6V.
10k
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large output capacitors on many switching regulators may be able to hold the supply pin of the LTC1154 above 3.5V sufficiently long that this extra filtering is not required. Because the LTC1154 is micropower in both the standby and ON state, the voltage drop across the supply filter is less than 2mV, and does not significantly alter the accuracy of the 100mV drain sense threshold voltage.
4.75V TO 5.25V VS 100 DS 5.6V IRLD024
W
UO
U
UO
+
10F
24V to 28V High-Side Switch with Thermal Shutdown
24V TO 28V
+
100F 3k
5V IN P OR CONTROL LOGIC EN LTC1154 STATUS GND G VS DS
+
18V 10F
MTP12N06 200k
SD PTC THERMISTOR (100C)* 24V TO 28V LOAD
*KEYSTONE RL2006-100-100-30-PT. MOUNT ON MOSFET OR LOAD HEAT SINK
LTC1154 * TA04
LTC1154 * TA06
11
LTC1154
TYPICAL APPLICATI
24V to 28V Switch with Bootstrapped Supply
24V TO 28V
+
100F 100k
5V IN P OR CONTROL LOGIC EN LTC1154 STATUS GND
VS DS G 200k SD PTC THERMISTOR (100C)* 1N4148
*KEYSTONE RL2006-100-100-30-PT. MOUNT ON MOSFET OR LOAD HEAT SINK. I Q(OFF) = 60A, IQ(ON) = 1mA.
A
51k pullup resistor should be connected between Status Output and 5V Logic Supply.
5V IN P OR CONTROL LOGIC EN LTC1154 STATUS GND G 0.22F SD VS DS 1N4148 200pF 100k 100k 10k 8 7 1 3 LT1431 6 5 4 5V/2A IRLR024
12
UO
18V
S
High-Side Relay Driver with Over-Current Protection and Status Feedback
12V
+
100F 2 0.02
+
10F 6.2k
5V IN P OR CONTROL LOGIC EN LTC1154 STATUS GND
VS 0.01F DS
10k 1N4148 MTD3055E
MTP15N06E
G 15V SD 1N4001
TO 12V LOAD
24V TO 28V LOAD
COIL CURRENT LIMITED TO 350mA. CONTACT CURRENT LIMITED TO 5A.
LTC1154 * TA07
LTC1154 * TA08
"4-Cell-to-5V" Extremely Low Voltage Drop Regulator with Over-Current Shutdown, Status Feedback, Ramped Turn-ON and 8A Standby Current
4-CELL BATTERY PACK
+
100F 0.036
+
470F ESR < 0.5
LTC1154 * TA09
LTC1154
TYPICAL APPLICATI UO S
Bank Controlled High-Side Switches with "Global" Thermal and Over-Voltage Shutdown
12V IN EN LTC1154 STATUS GND G 15V SD OUTPUT 1 IRLR024 VS 100 DS
+
470F
IN 5V EN 51k LTC1154 STATUS GND
VS DS G 15V SD OUTPUT 2
IRLR024
P OR CONTROL LOGIC
IN EN LTC1154 STATUS GND
VS DS G 15V SD OUTPUT 3
IRLR024
IN EN LTC1154 STATUS GND
VS DS G 15V SD PTC THERMISTOR (100C)*
LTC1154 * TA10
120k
IRLR024
OUTPUT 4 15V
*KEYSTONE RL2006-100-100-30-PT. MOUNT ON COMMON HEAT SINK.
13
LTC1154
TYPICAL APPLICATI UO
VS 0.22F 51k EN LTC1154 STATUS STATUS GND G SD 0.1F DS 1N4148 100k 100k 1k 1F
LTC1154 * TA11
S
12V Step-Up Regulator with Ultra-Low Standby Current, Over-Current Protection and Status Feedback
0.02 5V IRLZ24 50H 1N5820
+
470F
20
+
10k 1N4148
12V/1A 330F
+
47F ON/OFF IN
+
150F
5 VIN VSW LT1070 2 FB VC GND 3 1 4 10.72k 1%
1.24k 1%
12V Step-Up Regulator with 1A Over-Current Protection, Switch Status Feedback and Ramped Output
50H 5V
1N5820
+
150F 5 VIN
+
330F 1N4148 4 10.72k 1% ON/OFF 51k IN EN LTC1154 STATUS STATUS GND G 12V SD 0.22F VS 0.1F 1.24k 1% DS 1N4148 100k 100k IRF530 10k 0.1
VSW LT1070 2 FB VC GND 3 1 1k 1F
+
12V/1A 47F
LTC1154 * TA12
14
LTC1154
TYPICAL APPLICATI
12V RT 1M** ON/OFF 1M
+
CT 100F** VN2222LL
*KEYSTONE RL2006-100-100-30-PT. **AUTO-RESET PERIOD 800ms WITH COMPONENTS SHOWN
SCSI Termination Power Switch with 1A Over-Current Shutdown, Auto-Reset and Load Soft-Start
5V
1M
1M
ON/OFF
+
1F VN2222LL GND
Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of circuits as described herein will not infringe on existing patent rights.
UO
IN
S
Auto-Reset High-Side Switch with Over-Current and Over-Current Temperature Shutdown
+
100F 0.036 IN EN LTC1154 STATUS GND G 200k SD PTC THERMISTOR (100C)* 12V LOAD 18V MTP12N06 VS DS
LTC1154 * TA13
0.1
MTD3055EL
1N5817 4.25V/1A
+
100F 20 10k 1N4148
+
10F
VS 0.1F DS LTC1154 G SD
+
47F 1N4148 100k 100k
EN STATUS
0.22F
LTC1154 * TA14
15
LTC1154
PACKAGE DESCRIPTIO U
N8 Package 8-Lead Plastic Lead
0.300 - 0.320 (7.620 - 8.128) 0.045 - 0.065 (1.143 - 1.651) 0.130 0.005 (3.302 0.127) 8 0.065 (1.651) TYP 0.125 (3.175) MIN 0.020 (0.508) MIN 0.400 (10.160) MAX 7 6 5 0.250 0.010 (6.350 0.254) 1 2 3 4 0.018 0.003 (0.457 0.076)
0.009 - 0.015 (0.229 - 0.381)
(
+0.025 0.325 -0.015 8.255 +0.635 -0.381
)
0.045 0.015 (1.143 0.381) 0.100 0.010 (2.540 0.254)
S8 Package 8-Lead Plastic SOIC
0.010 - 0.020 x 45 (0.254 - 0.508) 0.008 - 0.010 (0.203 - 0.254) 0.016 - 0.050 0.406 - 1.270 0.053 - 0.069 (1.346 - 1.752) 0.004 - 0.010 (0.101 - 0.254) 0.189 - 0.197 (4.801 - 5.004) 8 7 6 5
0- 8 TYP
0.014 - 0.019 (0.355 - 0.483)
0.050 (1.270) BSC
0.228 - 0.244 (5.791 - 6.197)
0.150 - 0.157 (3.810 - 3.988)
1
2
3
4
16
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7487
(408) 432-1900 q FAX: (408) 434-0507 q TELEX: 499-3977
LT/GP 1192 10K REV 0
(c) LINEAR TECHNOLOGY CORPORATION 1992

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