LT1304_技术文档

UTC LT1304/LT1304-3.3V/LT1304-5.0V

LINEAR INTEGRATED CIRCUIT

MICROPOWER DC/DC

CONVERTERS WITH

LOW-BATTERY DETECTOR

ACTIVE IN SHUTDOWN

DESCRIPTION

The UTC LT1304 is a micropower step-up DC/DC

converter ideal for use in small, low voltage,

battery-operated systems. The devices operate from a

wide input supply range of 1.5V to 8V.

SOP-8

DIP-8

The UTC LT1304-3.3 and LT1304-5.0 generate

regulated outputs of 3.3V and 5V and the adjustable

LT1304 can deliver output voltages up to

25V.Quiescent current,120 μ A

in active mode,

decreases to just 10 μA in shutdown with the

low-battery detector still active. Peak switch current,

internally set at 1A,can be reduced by adding a single

resistor from the I^LIMpin to ground. The high speed

operation of the UTC LT1304 allows the use of small,

surface-mountable inductors and capacitors.

FEATURES

APPLICATIONS

*5V at 200mA from two cells.

*2-,3-,or 4-cell to 5V or 3.3V step-up

*Portable instruments

*10μA quiescent current in shutdown.

*Operates with V^INas low as1.5V

*Low battery detector active in shutdown

*Low switch VCESAT:370mV at 1A typical.

*120μA quiescent current in active mode.

*Bar code scanners

*Palmtop computers

*Diagnostic medical instrumentation.

*Personal data communicators/computers.

*Switching frequency up to 300kHz

*Programmable peak current with one resistor.

.

PIN CONFIGURATION

LBI

LBO

VIN

1

2

3

4

8

7

6

5

FB(SENSE)*

SHDN

ILI M

GND

SW

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UTC LT1304/LT1304-3.3V/LT1304-5.0V

LINEAR INTEGRATED CIRCUIT

ABSOLUTE MAXIMUM RATINGS

PARAMETER

Input Voltage

SYMBOL

RATING

UNIT

V

VIN

8

-0.4 ~ +25

VIN+0.3

5

SW Voltage

FB Voltage(LT1304)

ILIM Voltage(LT1304-3.3/LT1304-5.0)

SHDN Voltage

6

V

LBI Voltage

LBO Voltage

VIN

8

V

Maximum Power Dissipation

Junction Temperature

Operating Temperature Range

Storage Temperature Range

Lead Temperature (soldering,10sec)

PD

Tj

Topr

Tstg

500

125

0 ~ 70

-65 ~ +150

300

mW

°C

ELECTRICAL CHARACTERISTICS (VIN=2V,VSHDN=2V Unless otherwise noted.)

PARAMETER

Minimum Operating Voltage

Operating Voltage Range

Quiescent Current

TEST CONDITIONS

MIN TYP

1.5

MAX

1.65

8

200

15

50

1.26

25

UNIT

V

*

V^SHDN=2V,Not switching

V^SHDN=0V,VIN=2V

V^SHDN=0V,VIN=5V

µA

V

nA

µA

%/V

V

nA

mV

V

µA

V

120

7

Quiescent Current In Shutdown

27

Comparator Trip Point

FB Pin Bias Current

Sense Pin Leakage in Shutdown

Line Regulation

LBI Input Threshold

LBI Bias Current

LBI Input Hysteresis

LBO Output Voltage Low

LBO Output Leakage Current

SHDN Input Voltage High

SHDN Input Voltage Low

1.22

1.10

1.24

10

0.002

0.04

1.17

6

*

V^SHDN=0V,Fixed Output Versions

1

1.8V≤VIN≤8V

Falling Edge

0.15

1.25

20

65

0.4

0.1

35

ISINK=500µA

LBI=1.5V,LBO=5V

0.2

0.01

1.4

V

0.4

8

SHDN Pin Bias Current

V ^SHDN=5V

V ^SHDN=0V

µA

µs

%

A

mA

V

5

-2

-5

1

4

76

0.8

Switching Off Time

Switch On Time

Maximum Duty Cycle

1.5

6

2

8

88

1.2

Current Limit Not Asserted

ILIM Pin Open,VIN=5V

20K from I^LIMto GND

Isw=1A

80

1

Peak Switch Current

500

0.37

0.26

Switch Saturation Voltage

V

*

Isw=700mA

0.35

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LINEAR INTEGRATED CIRCUIT

PARAMETER

Switch Leakage

TEST CONDITIONS

Switch off, Vsw=5V

MIN TYP

0.01

MAX

7

UNIT

µA

The * denotes specifications which apply over the 0°C to 70°C operating temperature range.

PIN FUNCTIONS

PIN No.

1

SYMBOL

LBI

DESCRIPTION

Low Battery Detector Input. When voltage on this pin is less than

1.17V,detector output is low

Low Battery Detector Output. Open collector can sink up to 500µA.Low

battery detector remains active when device is shut down.

Input Supply. Must be bypassed close (<0.2”) to the pin. See required layout

in the Typical Applications

2

3

LBO

VIN

Collector of Power NPN. Keep copper traces on this pin short and direct to

minimize RFI

Device Ground. Must be low impedance; solder directly to ground plane

Current Limit Set Pin. Float for 1A peak switch current; a resistor to ground

will lower peak current

4

5

6

SW

GND

ILIM

Shutdown Input. When low, switching regulator is turned off. The

low-battery detector remains active. The SHDN input should not be left

floating. If SHDN is not used, tie the pin to V^IN

On the LT1304 (adjustable) this pin goes to the comparator input. On the

fixed-output versions, the pin connects to the resistor divider which sets output

voltage. The divider is disconnected from the pin during shutdown.

7

8

SHDN

FB/SENSE

TYPICAL APPLICATION

Efficiency

2-Cell to 5V Step-Up Converter with Low-Battery Detect

90

80

D1

22μH

1N5817

499K

604K

3

4

SW

70

60

V

IN

1

6

5V

200mA

100μF

LBO

LOW WHEN

8

2

LBI

SENSE

LT1304-5.0

+

2 CELLS

100K

100μF

LIM

NC

I

IBO

SHDN

7

SHUTDOWN

GND

V

BAT

＜2.2V

V

=3.3V

=2.5V

=1.8V

5

IN

50

40

0.01

1

10

100 500

LOAD CURRENT(mA)

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LINEAR INTEGRATED CIRCUIT

TYPICAL PERFORMANCE CHARACTERISTICS

Peak Switch Current Limit

Switch Saturation Voltage

500

1.3

1.2

1.1

Ta =25℃

400

300

200

1.0

0.9

0.8

0.7

0.6

100

0

-50

-25

0

25

50

75

100

0

0.2

0.4

0.6

0.8

1.0

1.2

Temperature(℃)

Switch Current (A)

On-and Off-times

Feedback Voltage

8

1.250

1.245

1.240

7

6

Maximum On-Time

1.235

1.230

5

4

3

1.225

1.220

1.215

Off-Time

2

1.210

1.205

1.200

1

0

-50

-25

0

25

50

75

100

-50

-25

0

25

50

75

100

Temperature(℃)

Feedback Pin Bias Current

Supply Current

20

300

250

Ta =25℃

18

16

14

12

VSHDN=VN

NOT SW ITCHING

200

150

10

8

100

6

4

2

0

VSHDN= 0 V

50

0

-50

-25

0

25

50

75

100

0

1

2

3

4

5

6

7

8

Temperature(℃)

Input Voltage (V)

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UTC LT1304/LT1304-3.3V/LT1304-5.0V

LINEAR INTEGRATED CIRCUIT

Load Transient

Response

Burst Mode Operation

VOUT

OVUT

100mV / DIV

100mV/DIV

AC COUPLED

Vsw

5V/DIV

I

500mA/DIV^L

ILOAD

200mA

0

20μs/DIV

100 μs / DIV

VIN=2.5V

VOUT=5V

ILOAD=185mA

L=22 μH

BLOCK DIAGRAMS

VIN

VOUT

+

L1

+

C1

C2

D1

LBO

2

VIN

SW

3

4

1.5V

UNDERVOLTA

GELOCKOUT

36mV

LBI

1

8

+

-

R1

7.2Ω

A2

R2

1K

-

A3

1.17V

BIAS

-1V

OFF

Q3

1K

R3

FB

-

TIMERS

ENABLE

A1

6μs ON

Q1

×200

Q2

1.5μs OFF

+

R4

×1

DRIVER

1.24V

VREF

SHUTDOWN

SHDN

GND

ILIM

7

6

5

Figure 1. LT1304 Block Diagram. Independent Low-Battery Detector A3 Remains Alive When Device Is in Shutdown

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UTC LT1304/LT1304-3.3V/LT1304-5.0V

LINEAR INTEGRATED CIRCUIT

LBO

VIN

SW

1

2

3

4

1.5V

UNDERVOLTA

GELOCKOUT

36mV

LBI

8

+

-

+

-

R1

A2

R2 7.2 Ω

A3

1K

1.17V

BIAS

-1V

OFF

Q3

1K

R3

590K

-

TIMERS

ENABLE

A1

6μs ON

Q1

×200

R4

Q2

×1

+

1.5μsOFF

DRIVER

1.24V

VREF

SHUTDOWN

ILIM

SHDN

GND

7

6

5

R4=355K

R4=195K

(LT1304-3.3V)

(LT1304-5.0V)

Figure 2. LT1304-3.3/LT1304-5.0 Block Diagram

OPERATION

The LT1304 operation can best be understood by examining the block diagram in Figure 1.Comparator A1monitors

the output voltage via resistor divider string R3/R4 at the FB pin. When V^FBis higher than the 1.24V reference,A2

and the timers are turned off. Only the reference, A1 and A3 consume current, typically 120µA.As V^FBdrops below

1.24V plus A1’s hysteresis (about 6mV),A1 enables the rest of the circuit. Power switch Q1 is then cycled on for 6µs,

or until current comparator A2 turns off the ON timer, Whichever comes first. Off-time is fixed at approximately 1.5µs.

Q1’s switching cause current to alternately build up in inductor L1 and discharge into output capacitor C2 via D1,

increasing the output voltage .As V^FBincreases enough to overcome C1’s hysteresis, switching action ceases. C2 is

left to supply current to the load until V^OUTdecreases enough to force A1’s output high, and the entire cycle repeats.

If switch current reaches 1A,causing A2 to trip, switch ON time is reduced. This allows continuous mode operation

during bursts.A2 monitors the voltage across 7.2Ωresistor R1,which is directly related to the switch current.Q2’s

collector current is set by the emitter-area ratio to 0.5% of Q1’s collector current. R1’s voltage drop exceeds

36mV,corresponding to 1A switch current,A2’s output goes high ,truncating the ON time part of the switch cycle. The

1A peak current can be reduced by tying a resistor between the I^LIMpin and ground, causing a voltage drop to

appear across R2.The drop offsets some of the 36mV reference voltage, lowering peak current. A 22K resistor limits

current to approximately 550mA.A capacitor connected between I^LIMand ground provides soft start. Shutdown is

accomplished by grounding the SHDN pin.

The low-battery detector A3 has its own 1.17V reference and is always on. The open collector output device can sink

up to 500µA.Approximately 35mV of hysteresis is built into A3 to reduce ”buzzing” as the battery voltage reaches the

trip level.

INDUCTOR SELECTION

Inductors used with the LT1304 must be capable of handling the worst-case peak switch current of 1.2A

without saturating. Open flux rod or drum core units may be biased into saturation by 20% with only a small

^{reduction in efficiency. For the majority of 2-cell or 3-cell input LT1304 applications, a 22}µH or 20µH inductor such

as the Sumida CD54-220 (drum) or Coiltronics CTX20-1 (toroid) will suffice. If switch current is reduced using the

ILIM pin, smaller inductors such as the Sumida CD43 series or Coilcraft DO1608 series can be used. Minimizing

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LINEAR INTEGRATED CIRCUIT

DCR is important for best efficiency. Ideally, the inductor DCR should be less than 0.05W, although the physical size

of such an inductor makes its use prohibitive in many space conscious applications. If EMI is a concern, such as

when sensitive analog circuitry is present, a toroidal inductor such as the Coiltronics CTX20-1 is suggested.

A special case exists where the VOUT/VIN differential is high, such as a 2V to 12V boost converter. If the required

duty cycle for continuous mode operation is higher than the LT1304 can provide, the converter must be designed

for discontinuous operation. This means that the inductor current decreases to zero during the switch OFF time. For

a simple step-up (boost) converter, duty cycle can be calculated by the following formula:

DC = 1 – [(V^IN– VSAT)/(VOUT + VD)]

where,

V^IN= Minimum input voltage

V^SAT= Switch saturation voltage (0.3V)

V^OUT= Output voltage

V^D= Diode forward voltage (0.4V)

If the calculated duty cycle exceeds the minimum LT1304 duty cycle of 76%, the converter should be designed for

discontinuous mode operation. The inductance must be low enough so that current in the inductor reaches the

peak current in a single cycle. Inductor value can be calculated by:

L = (V^IN– VSAT)(tON/1A)

where,

tON = Minimum on-time of LT1304 (4µs)

One advantage of discontinuous mode operation is that inductor values are usually quite low so very small units

can be used. Ripple current is higher than with continuous mode designs and efficiency will be somewhat less.

Capacitor Selection

Low ESR (Equivalent Series Resistance) capacitors should be used at the output of the LT1304 to minimize output

ripple voltage. High quality input bypassing is also required. For surface mount applications AVX TPS series

tantalum capacitors are recommended. These have been specifically designed for switch mode power supplies and

have low ESR along with high surge current ratings. A 100µF, 10V AVX TPS surface mount capacitor typically

limits output ripple voltage to 70mV when stepping up from 2V to 5V at a 200mA load. For through hole applications

Sanyo OS-CON capacitors offer extremely low ESR in a small package size. Again, if peak switch current is

reduced using the ILIM pin, capacitor requirements can be eased and smaller, higher ESR units can be used.

Diode Selection

Best performance is obtained with a Schottky rectifier such as the 1N5818. Motorola makes the MBRS130L

Schottky which is slightly better than the 1N5818 and comes in a surface mount package. For lower switch

currents, the MBR0530 is recommended. It comes in a very small SOD-123 package. Multiple 1N4148s in parallel

can be used in a pinch, although efficiency will suffer.

ILIM Function

The LT1304’s current limit (I^LIM) pin can be used for soft start. Upon start-up, the LT1304 will draw maximum

current (about 1A) from the supply to charge the output capacitor. Figure 3 shows V^OUTand VIN waveforms as the

device is turned on. The high current flow can create IR drops along supply and ground lines or cause the input

supply to drop out momentarily. By adding R1 and C1 as shown in Figure 4, the switch current is initially limited to

well under 1A as detailed in Figure 5. Current flowing into C1 from R1 and the I^LIMpin will eventually charge C1 and

R1 effectively takes C1 out of the circuit. R1 also provides a discharge path for C1 when SHUTDOWN is brought low

for turn-off.

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LINEAR INTEGRATED CIRCUIT

VOUT

2V/DIV

I IN

500mA/DIV

V ^SHDN

10V/DIV

1ms/DIV

Figure 3. Start-Up Response.Input Current Rises Quickly to

1A. VOUT Reaches 5V in Approximately 1ms.Output Drives

20mA Load

MBRS130L

22μH *

V

LBI

SW

SENSE

+

IN

100μF

5V

200mA

2 CELLS

LT1304-5.0

SHDN

IBO

R1

1M

I

+

GND

LIM

100 μF

+

C1

μF

SHUTDOWN

1

*SUMIDA CD54-220

Figure4.2-Cell to 5V/200mA Boost Converter Takes Four

External Parts.Components with Dashed Lines Are for

Soft Start(Optional)

If the full power capability of the LT1304 is not required,peak switch current can be limited by connecting a resistor

R^LIMfrom the ILIM pin to ground. With RLIM = 22k, peak switch current is reduced to approximately 500mA. Smaller

power components can then be used. The graph in Figure 6 shows switch current vs R^LIMresistor value.

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LINEAR INTEGRATED CIRCUIT

VOUT

2V/DIV

IIN

500mA/DIV

VSHDN

10V/DIV

1304 F05

1ms/DIV

Figure 5. Start-Up Response with 1μF/1MΩComponents

in Figure 2 Added. Input Current Is More Controlled. VOUT

Reaches 5V in6ms.Output Drives 20mA Load.

1000

900

800

700

600

500

400

100

RLIM(kΩ

1000

10

Figure 6.Peak Switch Current vs RLIM Value

LAYOUT/INPUT BYPASSING

The LT1304 high speed switching mandates careful attention to PC board layout. Suggested component place-ment

is shown in Figure 7.The input supply must have low impedance at AC and the input capacitor should be placed as

indicated in the figure. The value of this capacitor depends on how close the input supply is to the IC. In situations

where the input supply is more than a few inches away from the IC, a 47µF to 100µF solid tantalum bypass capacitor

is required. If the input supply is close to the IC, a 1µF ceramic capacitor can be used instead. The LT1304 switches

current in 1A pulses, so a low impedance supply must be available. If the power source (for example, a 2AA cell

battery) is within 1 or 2 inches of the IC, the battery itself provides bulk capacitance and the 1µF ceramic capacitor

acts to smooth voltage spikes at switch turn-on and turn –off. If the power source is far away from the IC, inductance

in the power source leads results in high impedance at high frequency. A local high capacitance bypass is then

required to restore low impedance at the IC.

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LINEAR INTEGRATED CIRCUIT

SHUTDOWN

1

2

8

7

LT1304

+

VIN

3

4

6

5

CIN

VOUT

+

COUT

GND (BATTERY AND LOAD RETURN)

Figure 7. Suggested Layout for Best Performance.Input Capacitor Placement as

Shown Is Highly Recommended.Switch Trace (pin 4) Copper Area Is Minimized

Low-Battery Detector

The LT1304 contains an independent low-battery detector that remains active when the device is shut down. This

detector, actually a hysteretic comparator, has an open collector output that can sink up to 500µA.The comparator

also operates below the switcher’s undervoltage lockout threshold, operating until V^INreaches approximately

1.4V.Figure 8 illustrates the input /output characteristic of the detector. Hysteresis is clearly evident in the figure.

VLBO

2V/DIV

VLBI

200mV/DIV

Figure 8. Low-Battery Detector Transfer Function.

Pull-Up R=22K,VIN=2V,Sweep Frequency=10Hz

Battery Life

How may hours does it work? This is the bottom line question that must be asked of any efficiency study. AA

alkaline cells are not perfect power sources. For efficient power transfer, energy must be taken from AA cells at a

rate that does not induce excessive loss. AA cells internal impedance, about 0.2Ω fresh and 0.5Ω end-of-life, results

in significant efficiency loss at high discharge rates. Figure 10 illustrates battery life vs load current of Figure 9’s

LT1304, 2-cell to 5V DC/DC converter. Note the accelerated decrease in hours at higher power levels. Figure 11

plots total watt hours vs load current. Watt hours are determined by the following formula:

WH = I^LOAD(5V)(H)

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LINEAR INTEGRATED CIRCUIT

L1

D1

22μH

VIN

SHDN

SW

VOUT

5V

SENSE

B1

200mA

2 CELLS

LT1304-5.0

LBI

ILIM

IBO

GND

+

C2

+

C1

100μF

Figure9.2-cell to 5V Converter Used in Battery Life Study

1000

100

10

1

200

100

10

LOAD CURRENT(mA)

Figure 10. Battery Life vs Current.Dots Specify

Actual Measurements

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LINEAR INTEGRATED CIRCUIT

6

5

4

3

2

1

0

1

200

10

100

LOAD CURRENT(mA)

Figure 11. Output Wall Hours vs Load Current.

Note Rapid Fall-Off at Higher Discharge Rates

Figure 11’s graph varies significantly from electrical efficiency plot pictured on the first page of this data sheet.

Why? As more current is drawn from the battery, voltage drop across the cells’ internal impedance increases. This

causes internal power loss (heating), reducing cell terminal voltage. Since the regulator input acts as a negative

resistance, more current is drawn from the battery as the terminal voltage decreases. This positive feedback action

compounds the problem.

Figure 12 shows overall energy conversion efficiency, assuming availability of 6.5WH of battery energy. This

efficiency approximates the electrical efficiency at load current levels from 1mA to 10mA, but drops severely at

load currents above 10mA (load power above 50mW). The moral of the story is this: if your system needs 5V at

more than 40mA to 50mA, consider using a NiCd battery (1/10 the internal impedance) instead of a AA cell alkaline

battery.

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LINEAR INTEGRATED CIRCUIT

100

90

80

70

60

50

40

30

20

10

0

200

1

10

100

LOAD CURRENT(mA)

Figure 12. Overall System Efficiency Including Battery Efficiency

vs Load Current.Internal lmpedance of Alkaline AA Cells

Accounts for Rapid Drop in Efficiency at Higher Load Current

TYPICAL CHARACTERISTICS

Super Burst Efficiency

90

80

Super Burst Low IQ DC/DC Converter

MBR0530

VIN=3V

VIN=2V

〜

IQ〜10 μA

〜

33 μH

0.0

1

μF

200K

47K

70

60

2N3906

V IN

LBO

LT1304

SW

5V

2 CELLS

LBI

+

100mA

3.83M

1%

100μF

FB

ILIM

GND

+

1.21M

220μF

SHDN

50

40

47K

22K

0.1

1.0

10

100

0.01

Load Current (m)

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LINEAR INTEGRATED CIRCUIT

2-Cell to 3.3V ConverterEfficiency

2-Cell to 3.3V Boost Converter

90

L1

MBRS130L

22μH

80

70

+

C1

100μF

V

SW

IN

3.3V

SENSE

300mA

60

50

2 CELLS

LT130-3.3

SHDN

C2

+

GND

I

VIN=3.3V

VIN=2.5V

VIN=1.8V

LIM

μF

100

10V

40

30

NC

SHUTDOWN

0.1

1

10

100

1000

Load Current (mA)

3.3V SEPIC Efficiency

3.3V SEPIC Efficiency(Step-Up/Step-Down Converter)

80

C1

L1A

1μF

75

70

VIN

2

1

2.5V TO 8V

4

3

C2

L1B

*

+

MBRS130L

VIN

SW

μF

47

65

60

16V

LT1304-3.3

3.3V

SENSE

GND

SHDN

I LIM

SHUTDOWN

300mA

VIN=4.5V

VIN=3.5V

VIN=2.5V

C3

+

55

50

100μF

N

C

10V

1

10

100

500

Load Current (mA)

5V SPEC (Step-Up/Step-Down Converter)

5V SEPIC Efficiency

C1

80

L1A

1μF

V

IN

2

1

3V TO 8V

75

70

4

3

+

MBRS130L

L1B

V

SW

IN

47μF

16V

LT1304-5.0

65

60

5V

200mA

SENSE

GND

SHDN

I LIM

SHUTDOWN

VIN=6V

VIN=5V

VIN=4V

VIN=3V

+

100 μF

10V

NC

55

50

1

10

100

500

Load Current (mA)

UTC UNISONIC TECHNOLOGIES CO., LTD.

14

QW-R103-018,A

UTC LT1304/LT1304-3.3V/LT1304-5.0V

LINEAR INTEGRATED CIRCUIT

5V to 12V DC/DC Converter

5V to 12V Converter Efficiency

90

85

L1

D1

22μH

MBRS130L

5V

VIN

SW

+

80

75

47μF

LT1304

1.07M

1%

12V

200mA

FB

SHDN

SHUTDONW

GND

+

47μF

124K

1%

16V

70

65

1

10

100

300

Load Current(mA)

Single Li-lon Cell to 5V Converter with Load Disconnect at Vin＜2.7V

MBRS130L

22μH

5V

1 μF

+

562k

220k

1%

+

100μF

Vout

VIN1

Vout

VIN2

VIN

SW

SENSE

NC

ILIM

SINGLE

LI-ION

CELL

NC

LBI

LT1304-5.0

VINS

EN

VIN3

GND

432k

1%

SHDN

IBO

GND

UTC UNISONIC TECHNOLOGIES CO., LTD.

15

QW-R103-018,A

UTC LT1304/LT1304-3.3V/LT1304-5.0V

LINEAR INTEGRATED CIRCUIT

Negative LCD Bias Generator

L1*

10μH

MBR0530

1.69M

1μ F

CERAMIC

VIN

SW

1%

-VOUT

-14V TO -22V

FB

+

1mA TO 10mA

LT1304

1M

1%

MBR0530

+

90.9K

1%

47μ F

2 CELLS

1000

pF

10μF

110K

1%

ILIM

GND

35V

+

MBR0530

EFFICIENCY =70% TO 75% AT

ILOAD≧2mA

22K

3.3μF

VOLTAGE ADJUST 1kHz PWM INPUT 0V TO 5V

Electroluminescent Panel Driver with 200Hz Oscillator

1μF

MUR160

600V

200V

47μF

1:12

VIN

4

6

2V TO 7V

+

3

1

EL PANEL

CPANEL≦ 20nF

10M

MBR0530

VIN

SHDN

(3.3M*3)

5V=OPERATE

SW

FB

0V=SHUTDOWN

22K

FMMT458

22K

75K

51K

LBO LT1304

22K

2N3906

+

50K

INTENSITY

ADJUST

1nF

22K

LBI

ILIM

NC

GND

3.3K

0.01μF

1/2 BAW56

200Hz

UTC UNISONIC TECHNOLOGIES CO., LTD.

16

QW-R103-018,A

UTC LT1304/LT1304-3.3V/LT1304-5.0V

LINEAR INTEGRATED CIRCUIT

2-to 4-Cell to 1kV Step-Up Converter

0.01μF

0.01μF 0.01μF

0.01μF

T1

4

VIN

+

3

1

2V TO 6V

47μF

0.01μF

0.01μF 0.01μF

6

MBR0530

VIN

VOUT

1kV

SW

FB

0.1μF

R1

500M

250μA

R2

620K

LT1304

SHDN

ILIM

R1

SHUTDOWN

VOUT =1.24V(1+

)

R2

GND

NC

2- TO 4- Cell to 5V Converter with Output Disconnect

2K

L1

MBRS130L

22μH

VIN

2V TO 6V

ZTX788B

SW

VIN

5V

SENSE

100mA

+

47μF

LT1304-5.0

SHDN

ILIM

+

GND

22μF

220μF

NC

SHUTDOWN

UTC UNISONIC TECHNOLOGIES CO., LTD.

17

QW-R103-018,A

UTC LT1304/LT1304-3.3V/LT1304-5.0V

LINEAR INTEGRATED CIRCUIT

2- Cell to 5V Converter with Auxiliary 10V Output

MBR0530

10V

+

20mA

1μF

CERAMIC

10μF

L1

22μH

MBR0530

MBRS130L

V

IN

SW

5V

150mA

+

100μ

SENSE

2CELLS

F

LT1304-5.0

SHDN

+

I

GND

10μF

LIM

SHUTDOWN

NC

2- Cell to 5V Converter with Auxiliary -5V Output

L1

22μH

MBRS130L

SW

SENSE

V

IN

5V

150mA

+

100μF

2 CELLS

1μF

CERAMIC

LT1304-5.0

MBR0530

SHDN

-5V

20mA

I

GND

LIM

10μF

+

NC

SHUTDOWN

MBR0530

UTC UNISONIC TECHNOLOGIES CO., LTD.

18

QW-R103-018,A

UTC LT1304/LT1304-3.3V/LT1304-5.0V

LINEAR INTEGRATED CIRCUIT

UTC assumes no responsibility for equipment failures that result from using products at values that

exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or

other parameters) listed in products specifications of any and all UTC products described or contained

herein. UTC products are not designed for use in life support appliances, devices or systems where

malfunction of these products can be reasonably expected to result in personal injury. Reproduction in

whole or in part is prohibited without the prior written consent of the copyright owner. The information

presented in this document does not form part of any quotation or contract, is believed to be accurate

and reliable and may be changed without notice.

UTC UNISONIC TECHNOLOGIES CO., LTD.

19

QW-R103-018,A


型号：	LT1304
厂家：	Unisonic Technologies
描述：	MICROPOWER DC/DC CONVERTERS WITH LOW-BATTERY DETECTOR ACTIVE IN SHUTDOWN 微功耗DC /对于低电池电压检测器DC转换器活跃在关断转换器电池
文件：	总19页 (文件大小：268K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

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