Motorola UC3845BVD1, UC3845BVD, UC3845BN, UC3845BD1R2, UC3845BD1 Datasheet

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High Performance

Current Mode Controllers

The UC3844B, UC3845B series are high performance fixed frequency current mode controllers. They are specifically designed for Off±Line and dc±to±dc converter applications offering the designer a cost±effective solution with minimal external components. These integrated circuits feature an oscillator, a temperature compensated reference, high gain error amplifier, current sensing comparator, and a high current totem pole output ideally suited for driving a power MOSFET.

Also included are protective features consisting of input and reference undervoltage lockouts each with hysteresis, cycle±by±cycle current limiting, a latch for single pulse metering, and a flip±flop which blanks the output off every other oscillator cycle, allowing output deadtimes to be programmed from 50% to 70%.

These devices are available in an 8±pin dual±in±line and surface mount (SO±8) plastic package as well as the 14±pin plastic surface mount (SO±14). The SO±14 package has separate power and ground pins for the totem pole output stage.

The UCX844B has UVLO thresholds of 16 V (on) and 10 V (off), ideally suited for off±line converters. The UCX845B is tailored for lower voltage applications having UVLO thresholds of 8.5 V (on) and 7.6 V (off).

Trimmed Oscillator for Precise Frequency Control

Oscillator Frequency Guaranteed at 250 kHz

Current Mode Operation to 500 kHz Output Switching Frequency

Output Deadtime Adjustable from 50% to 70%

Automatic Feed Forward Compensation

Latching PWM for Cycle±By±Cycle Current Limiting

Internally Trimmed Reference with Undervoltage Lockout

High Current Totem Pole Output

Undervoltage Lockout with Hysteresis

Low Startup and Operating Current

 

 

Simplified Block Diagram

 

 

 

 

 

VCC

7(12)

Vref

 

5.0V

VCC

 

 

Undervoltage

 

Reference

8(14)

 

Lockout

R

 

 

 

 

 

 

 

 

 

 

Vref

 

VC

 

R

Undervoltage

 

 

 

Lockout

 

7(11)

 

 

 

 

RT/CT

 

Oscillator

 

Output

 

 

6(10)

4(7)

 

Latching

 

 

 

 

Voltage

 

PWM

 

Power

 

 

 

 

 

 

Ground

Feedback

 

 

 

 

 

 

5(8)

Input

Error

 

 

2(3)

 

 

 

Output/

Amplifier

 

 

Current

Compensation

 

 

 

Sense Input

1(1)

 

 

 

3(5)

Gnd 5(9)

Pin numbers in parenthesis are for the D suffix SO±14 package.

UC3844B, 45B UC2844B, 45B

HIGH PERFORMANCE

CURRENT MODE

CONTROLLERS

N SUFFIX

PLASTIC PACKAGE

CASE 626

 

8

 

1

D1 SUFFIX

 

PLASTIC PACKAGE

 

CASE 751

8

(SO±8)

1

D SUFFIX

 

PLASTIC PACKAGE

14

CASE 751A

1

(SO±14)

PIN CONNECTIONS

Compensation

 

 

 

 

 

 

Vref

 

1

 

 

 

 

8

 

Voltage Feedback

 

 

 

 

 

 

VCC

 

2

 

 

 

 

7

 

Current Sense

 

 

 

 

 

 

Output

 

3

 

 

 

 

6

 

 

RT/CT

4

 

 

 

 

 

Gnd

 

 

 

 

 

 

5

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(Top View)

 

 

Compensation

1

 

 

V

 

 

 

 

14

 

 

 

 

 

 

 

 

 

ref

 

 

NC

2

 

 

 

13

NC

 

Voltage Feedback

3

 

 

 

12

VCC

 

 

NC

4

 

 

 

11

V

 

Current Sense

 

 

 

 

 

 

C

 

5

 

 

 

10

Output

 

 

NC

6

 

 

 

9

Gnd

 

 

RT/CT

7

 

 

 

8

Power Ground

 

 

 

(Top View)

 

 

 

 

 

 

 

 

 

 

ORDERING INFORMATION

 

 

 

 

 

 

Device

 

Operating

 

Package

Temperature Range

 

 

 

 

 

 

 

 

 

 

 

 

UC384XBD

 

 

 

 

 

 

 

 

SO±14

UC384XBD1

TA = 0° to + 70°C

SO±8

UC384XBN

 

 

 

 

 

 

 

 

Plastic

 

 

 

 

 

 

 

 

 

 

UC284XBD

 

 

 

 

 

 

 

 

SO±14

 

TA = ± 25° to + 85°C

 

UC284XBD1

SO±8

UC284XBN

 

 

 

 

 

 

 

 

Plastic

 

 

 

 

 

 

 

 

 

 

UC384XBVD

TA = ± 40° to +105°C

SO±14

 

 

UC384XBVD1

SO±8

 

 

 

 

 

 

 

 

 

 

UC384XBVN

 

 

 

 

 

 

 

 

Plastic

 

 

 

 

 

 

 

 

 

 

X indicates either a 4 or 5 to define specific device part numbers.

Motorola, Inc. 1996 Rev 1

UC3844B, 45B UC2844B, 45B

MAXIMUM RATINGS

Rating

Symbol

Value

Unit

 

 

 

 

Total Power Supply and Zener Current

(ICC + IZ)

30

mA

Output Current, Source or Sink (Note 1)

IO

1.0

A

Output Energy (Capacitive Load per Cycle)

W

5.0

μJ

 

 

 

 

Current Sense and Voltage Feedback Inputs

Vin

± 0.3 to + 5.5

V

Error Amp Output Sink Current

IO

10

mA

Power Dissipation and Thermal Characteristics

 

 

 

D Suffix, Plastic Package, SO±14 Case 751A

 

 

 

Maximum Power Dissipation @ TA = 25°C

PD

862

mW

Thermal Resistance, Junction±to±Air

RθJA

145

°C/W

D1 Suffix, Plastic Package, SO±8 Case 751

 

 

 

Maximum Power Dissipation @ TA = 25°C

PD

702

mW

Thermal Resistance, Junction±to±Air

RθJA

178

°C/W

N Suffix, Plastic Package, Case 626

 

 

 

Maximum Power Dissipation @ TA = 25°C

PD

1.25

W

Thermal Resistance, Junction±to±Air

RθJA

100

°C/W

Operating Junction Temperature

TJ

+150

°C

Operating Ambient Temperature

TA

 

°C

UC3844B, UC3845B

 

0 to + 70

 

UC2844B, UC2845B

 

± 25 to + 85

 

 

 

 

 

Storage Temperature Range

Tstg

± 65 to +150

°C

ELECTRICAL CHARACTERISTICS (VCC = 15 V [Note 2], RT = 10 k, CT = 3.3 nF. For typical values TA = 25°C, for min/max values TA is the operating ambient temperature range that applies [Note 3], unless otherwise noted.)

 

 

 

 

UC284XB

 

UC384XB, XBV

 

 

 

 

 

 

 

 

 

 

 

 

Characteristic

Symbol

Min

 

Typ

 

Max

Min

Typ

Max

Unit

 

 

 

 

 

 

 

 

 

 

 

 

REFERENCE SECTION

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reference Output Voltage (IO = 1.0 mA, TJ = 25°C)

Vref

 

4.95

 

5.0

 

5.05

4.9

5.0

5.1

V

Line Regulation (VCC = 12 V to 25 V)

Regline

±

 

2.0

 

20

±

2.0

20

mV

Load Regulation (IO = 1.0 mA to 20 mA)

Regload

±

 

3.0

 

25

±

3.0

25

mV

Temperature Stability

TS

 

±

 

0.2

 

±

±

0.2

±

mV/°C

Total Output Variation over Line, Load, and Temperature

Vref

 

4.9

 

±

 

5.1

4.82

±

5.18

V

Output Noise Voltage (f = 10 Hz to 10 kHz, TJ = 25°C)

Vn

 

±

 

50

 

±

±

50

±

μV

Long Term Stability (TA = 125°C for 1000 Hours)

S

 

±

 

5.0

 

±

±

5.0

±

mV

Output Short Circuit Current

ISC

 

± 30

 

± 85

 

±180

± 30

± 85

±180

mA

OSCILLATOR SECTION

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Frequency

fOSC

 

 

 

 

 

 

 

 

 

kHz

TJ = 25°C

 

 

49

 

52

 

55

49

52

55

 

TA = Tlow to Thigh

 

 

48

 

±

 

56

48

±

56

 

TJ = 25°C (RT = 6.2 k, CT = 1.0 nF)

 

 

225

 

250

 

275

225

250

275

 

Frequency Change with Voltage (VCC = 12 V to 25 V)

fOSC/

V

±

 

0.2

 

1.0

±

0.2

1.0

%

Frequency Change with Temperature

fOSC/

T

±

 

1.0

 

±

±

0.5

±

%

TA = Tlow to Thigh

 

 

 

 

 

 

 

 

 

 

 

Oscillator Voltage Swing (Peak±to±Peak)

VOSC

 

±

 

1.6

 

±

±

1.6

±

V

Discharge Current (VOSC = 2.0 V)

Idischg

 

 

 

 

 

 

 

 

 

mA

TJ = 25°C

 

 

7.8

 

8.3

 

8.8

7.8

8.3

8.8

 

TA = Tlow to Thigh (UC284XB, UC384XB)

 

 

7.5

 

±

 

8.8

7.6

±

8.8

 

(UC384XBV)

 

 

±

 

±

 

±

7.2

±

8.8

 

 

 

 

 

 

 

 

 

 

 

 

 

NOTES: 1. Maximum package power dissipation limits must be observed.

2.Adjust VCC above the Startup threshold before setting to 15 V.

3.Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible.

Tlow =

0°C for UC3844B, UC3845B

Thigh =

+ 70°C for UC3844B, UC3845B

=

± 25°C for UC2844B, UC2845B

=

+ 85°C for UC2844B, UC2845B

=

± 40°C for UC3844BV, UC3845BV

=

+105°C for UC3844BV, UC3845BV

2

MOTOROLA ANALOG IC DEVICE DATA

UC3844B, 45B UC2844B, 45B

ELECTRICAL CHARACTERISTICS (VCC = 15 V [Note 2], RT = 10 k, CT = 3.3 nF. For typical values TA = 25°C, for min/max values TA is the operating ambient temperature range that applies [Note 3], unless otherwise noted.)

 

 

 

 

 

 

UC284XB

 

UC384XB, XBV

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Characteristic

 

 

Symbol

Min

 

Typ

 

Max

Min

Typ

Max

Unit

 

 

 

 

 

 

 

 

 

 

 

 

 

ERROR AMPLIFIER SECTION

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Voltage Feedback Input (VO = 2.5 V)

 

 

VFB

2.45

 

2.5

 

2.55

2.42

2.5

2.58

V

Input Bias Current (VFB = 5.0 V)

 

 

IIB

±

 

± 0.1

 

±1.0

±

± 0.1

± 2.0

μA

Open Loop Voltage Gain (VO = 2.0 V to 4.0 V)

 

 

AVOL

65

 

90

 

±

65

90

±

dB

Unity Gain Bandwidth (TJ = 25°C)

 

 

BW

0.7

 

1.0

 

±

0.7

1.0

±

MHz

Power Supply Rejection Ratio (VCC = 12 V to 25 V)

 

PSRR

60

 

70

 

±

60

70

±

dB

Output Current

 

 

 

 

 

 

 

 

 

 

 

mA

Sink (VO = 1.1 V, VFB = 2.7 V)

 

 

ISink

2.0

 

12

 

±

2.0

12

±

 

Source (VO = 5.0 V, VFB = 2.3 V)

 

 

ISource

± 0.5

 

±1.0

 

±

± 0.5

±1.0

±

 

Output Voltage Swing

 

 

 

 

 

 

 

 

 

 

 

V

High State (RL = 15 k to ground, VFB = 2.3 V)

 

 

VOH

5.0

 

6.2

 

±

5.0

6.2

±

 

Low State (RL = 15 k to Vref, VFB = 2.7 V)

 

 

VOL

 

 

 

 

 

 

 

 

 

(UC284XB, UC384XB)

 

 

 

±

 

0.8

 

1.1

±

0.8

1.1

 

(UC384XBV)

 

 

 

±

 

±

 

±

±

0.8

1.2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CURRENT SENSE SECTION

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Current Sense Input Voltage Gain (Notes 4 & 5)

 

 

AV

 

 

 

 

 

 

 

 

V/V

(UC284XB, UC384XB)

 

 

 

2.85

 

3.0

 

3.15

2.85

3.0

3.15

 

(UC384XBV)

 

 

 

±

 

±

 

±

2.85

3.0

3.25

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Maximum Current Sense Input Threshold (Note 4)

 

 

Vth

 

 

 

 

 

 

 

 

V

(UC284XB, UC384XB)

 

 

 

0.9

 

1.0

 

1.1

0.9

1.0

1.1

 

(UC384XBV)

 

 

 

±

 

±

 

±

0.85

1.0

1.1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Power Supply Rejection Ratio

 

 

PSRR

±

 

70

 

±

±

70

±

dB

(VCC = 12 V to 25 V) (Note 4)

 

 

 

 

 

 

 

 

 

 

 

 

Input Bias Current

 

 

IIB

±

 

± 2.0

 

±10

±

± 2.0

±10

μA

Propagation Delay (Current Sense Input to Output)

 

 

tPLH(In/Out)

±

 

150

 

300

±

150

300

ns

OUTPUT SECTION

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Output Voltage

 

 

 

 

 

 

 

 

 

 

 

V

Low State

(ISink = 20 mA)

 

 

VOL

±

 

0.1

 

0.4

±

0.1

0.4

 

 

(ISink = 200 mA, UC284XB, UC384XB)

 

 

±

 

1.6

 

2.2

±

1.6

2.2

 

 

(ISink = 200 mA, UC384XBV)

 

 

 

±

 

±

 

±

±

1.6

2.3

 

High State

(ISource = 20 mA, UC284XB, UC384XB)

 

VOH

13

 

13.5

 

±

13

13.5

±

 

 

(ISource = 20 mA, UC384XBV)

 

 

 

±

 

±

 

±

12.9

±

±

 

 

(ISource = 200 mA)

 

 

 

12

 

13.4

 

±

12

13.4

±

 

Output Voltage with UVLO Activated

 

 

VOL(UVLO)

±

 

0.1

 

1.1

±

0.1

1.1

V

VCC = 6.0 V, ISink = 1.0 mA

 

 

 

 

 

 

 

 

 

 

 

 

Output Voltage Rise Time (CL = 1.0 nF, TJ = 25°C)

 

 

tr

±

 

50

 

150

±

50

150

ns

Output Voltage Fall Time (CL = 1.0 nF, TJ = 25°C)

 

 

tf

±

 

50

 

150

±

50

150

ns

UNDERVOLTAGE LOCKOUT SECTION

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Startup Threshold

 

 

Vth

 

 

 

 

 

 

 

 

V

UCX844B, BV

 

 

 

15

 

16

 

17

14.5

16

17.5

 

UCX845B, BV

 

 

 

7.8

 

8.4

 

9.0

7.8

8.4

9.0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Minimum Operating Voltage After Turn±On

 

 

VCC(min)

 

 

 

 

 

 

 

 

V

UCX844B, BV

 

 

 

9.0

 

10

 

11

8.5

10

11.5

 

UCX845B, BV

 

 

 

7.0

 

7.6

 

8.2

7.0

7.6

8.2

 

 

 

 

 

 

 

 

 

 

 

 

NOTES: 2. Adjust VCC above the Startup threshold before setting to 15 V.

 

 

 

 

 

 

 

 

 

3. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible.

 

 

 

Tlow = 0°C for UC3844B, UC3845B

Thigh = + 70°C for UC3844B, UC3845B

 

 

 

 

 

 

 

 

 

= ± 25°C for UC2844B, UC2845B

 

= + 85°C for UC2844B, UC2845B

 

 

 

 

 

 

 

 

 

= ± 40°C for UC3844BV, UC3845BV

 

= +105°C for UC3844BV, UC3845BV

 

 

 

 

 

4. This parameter is measured at the latch trip point with VFB = 0 V.

5. Comparator gain is defined as: AV =

DV Output Compensation

DV Current Sense Input

 

MOTOROLA ANALOG IC DEVICE DATA

3

 

UC3844B, 45B UC2844B, 45B

ELECTRICAL CHARACTERISTICS (VCC = 15 V [Note 2], RT = 10 k, CT = 3.3 nF. For typical values TA = 25°C, for min/max values TA is the operating ambient temperature range that applies [Note 3], unless otherwise noted.)

 

 

 

UC284XB

 

UC384XB, XBV

 

 

 

 

 

 

 

 

 

 

 

 

 

Characteristic

 

Symbol

Min

 

Typ

 

Max

Min

Typ

Max

Unit

 

 

 

 

 

 

 

 

 

 

 

 

PWM SECTION

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Duty Cycle

 

 

 

 

 

 

 

 

 

 

%

Maximum (UC284XB, UC384XB)

 

DC(max)

47

 

48

 

50

47

48

50

 

(UC384XBV)

 

 

±

 

±

 

±

46

48

50

 

Minimum

 

DC(min)

±

 

±

 

0

±

±

0

 

TOTAL DEVICE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Power Supply Current

 

ICC

 

 

 

 

 

 

 

 

mA

Startup (VCC = 6.5 V for UCX845B,

 

 

±

 

0.3

 

0.5

±

0.3

0.5

 

14 V for UCX844B, BV)

 

 

 

 

 

 

 

 

 

 

 

Operating (Note 2)

 

 

±

 

12

 

17

±

12

17

 

 

 

 

 

 

 

 

 

 

 

 

 

Power Supply Zener Voltage (ICC = 25 mA)

 

VZ

30

 

36

 

±

30

36

±

V

NOTES: 2. Adjust VCC above the Startup threshold before setting to 15 V.

 

 

 

 

 

 

 

 

 

3. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible.

 

 

 

Tlow = 0°C for UC3844B, UC3845B

Thigh = + 70°C for UC3844B, UC3845B

 

 

 

 

 

 

 

= ± 25°C for UC2844B, UC2845B

= + 85°C for UC2844B, UC2845B

 

 

 

 

 

 

 

= ± 40°C for UC3844BV, UC3845BV

= +105°C for UC3844BV, UC3845BV

 

 

 

 

 

Figure 1. Timing Resistor versus Oscillator Frequency

 

80

 

 

 

 

VCC

= 15 V

 

50

 

 

 

 

 

 

 

 

 

 

°

Ω)

 

 

 

 

 

TA = 25 C

(k

 

 

 

 

 

 

 

RESISTOR

20

 

 

 

 

 

 

8.0

 

 

 

 

 

 

, TIMING

5.0

 

 

 

 

 

 

 

 

 

 

 

 

 

T

 

 

 

 

 

 

 

R

2.0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NOTE: Output switches at

 

 

 

 

 

1/2 the oscillator frequency

 

 

 

 

 

0.8

 

 

 

 

 

 

 

10 k

20 k

50 k

100 k

200 k

500 k

1.0 M

fOSC, OSCILLATOR FREQUENCY (kHz)

Figure 2. Output Deadtime versus Oscillator Frequency

 

75

1.

CT = 10 nF

 

 

 

 

3

DEADTIME

 

 

 

 

 

70

2.

CT = 5.0 nF

 

 

 

 

 

3.

CT = 2.0 nF

 

 

 

2

 

 

4.

CT = 1.0 nF

 

 

 

4

OUTPUT

65

5.

CT = 500 pF

 

 

 

 

 

6.

CT = 200 pF

 

 

 

1

 

 

7.

CT = 100 pF

 

 

 

 

 

PERCENT

60

 

 

 

 

 

 

 

 

 

 

 

 

 

 

7

55

 

 

 

 

 

 

5

% DT,

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

6

 

50

 

 

 

 

 

 

 

 

 

 

 

 

 

 

10 k

20 k

50 k

100 k

200 k

500 k

1.0 M

fOSC, OSCILLATOR FREQUENCY (kHz)

Figure 3. Error Amp Small Signal

Transient Response

VCC = 15 V

2.55 V AV = ±1.0

TA = 25°C

2.5V

2.45V

0.5 μs/DIV

20 mV/DIV

3.0 V

2.5 V

2.0 V

Figure 4. Error Amp Large Signal

Transient Response

VCC = 15 V

AV = ±1.0

TA = 25°C

200 mV/DIV

1.0 μs/DIV

4

MOTOROLA ANALOG IC DEVICE DATA

Motorola UC3845BVD1, UC3845BVD, UC3845BN, UC3845BD1R2, UC3845BD1 Datasheet

 

 

 

 

 

UC3844B, 45B UC2844B, 45B

 

 

 

 

 

Figure 5. Error Amp Open Loop Gain and

 

 

 

 

Figure 6. Current Sense Input Threshold

 

 

 

 

Phase versus Frequency

 

 

0

(V)

1.2

versus Error Amp Output Voltage

 

(dB)

100

 

 

 

 

 

 

 

 

 

 

 

 

 

 

VCC = 15 V

 

 

 

VCC = 15 V

 

 

 

GAIN

80

 

 

 

VO = 2.0 V to 4.0 V

30

CURRENTSENSE INPUTTHRESHOLD

1.0

 

 

 

 

 

 

 

Gain

RL = 100 k

 

 

 

 

 

 

 

VOLTAGE

 

 

 

 

°

 

 

 

 

 

 

 

60

 

 

 

TA = 25 C

 

60

0.8

 

 

 

 

 

 

 

 

 

 

TA = 25°C

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

40

 

 

 

 

 

 

90

0.6

 

 

 

 

LOOP

 

 

 

 

Phase

TA = 125°C

 

 

 

 

 

 

 

 

 

 

 

 

 

20

 

 

 

 

 

 

120

0.4

 

 

 

 

OPEN

 

 

 

 

 

 

 

TA = ± 55°C

 

 

 

 

 

 

 

 

 

150

0.2

 

 

 

,

0

 

 

 

 

 

 

 

 

 

 

VOL

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(DEGREES)PHASEEXCESSφ,

 

 

 

 

 

A

± 20

 

 

 

 

 

 

180

,

0

 

 

 

 

 

 

 

 

 

 

th

 

 

 

 

 

10

100

1.0 k

10 k

100 k

1.0 M

10 M

V

0

2.0

4.0

6.0

8.0

 

 

 

 

 

f, FREQUENCY (Hz)

 

 

 

 

 

VO, ERROR AMP OUTPUT VOLTAGE (VO)

 

 

 

Figure 7. Reference Voltage Change

 

(mV)

0

 

versus Source Current

 

 

 

 

 

 

 

 

 

 

 

 

VCC = 15 V

 

CHANGE

 

 

 

 

 

 

± 4.0

 

 

 

 

 

 

 

 

 

 

 

 

 

VOLTAGE

± 8.0

 

 

 

 

 

 

± 12

 

 

 

 

TA = ± 55°C

 

, REFERENCE

 

TA = 125°C

 

 

 

± 16

 

 

 

 

 

 

 

 

 

 

 

± 20

 

 

 

 

 

 

ref

 

 

 

TA = 25°C

 

 

 

V

± 24

 

 

 

 

 

 

 

 

 

 

 

 

 

0

20

40

60

80

100

120

 

 

 

Iref, REFERENCE SOURCE CURRENT (mA)

 

(mA)

 

Figure 8. Reference Short Circuit Current

 

110

 

versus Temperature

 

 

 

 

 

 

 

 

 

CURRENT

 

 

 

 

 

VCC = 15 V

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RL 0.1 Ω

 

 

 

 

 

 

 

 

 

SHORT CIRCUIT

90

 

 

 

 

 

 

 

70

 

 

 

 

 

 

 

, REFERENCE

 

 

 

 

 

 

 

50

 

 

 

 

 

 

 

SC

± 25

0

25

50

75

100

125

± 55

I

 

 

 

TA, AMBIENT TEMPERATURE (°C)

 

OUTPUT, CHANGEVOLTAGE mV/DIV)(2.0

O V

Figure 9. Reference Load Regulation

VCC = 15 V

IO = 1.0 mA to 20 mA

TA = 25°C

2.0 ms/DIV

OUTPUT, CHANGEVOLTAGE mV/DIV)(2.0

O V

Figure 10. Reference Line Regulation

VCC = 12 V to 25 V

TA = 25°C

2.0 ms/DIV

MOTOROLA ANALOG IC DEVICE DATA

5

 

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