Datasheet GL494 Datasheet (HEI)

1

Q

+ + −

−

Description

The GL494 incorporates on a single monolithic chip all the
functions required in the construction of a pulse-width­modulation control circuit. Designed primarily for power
supply control, the GL494 contains an on-chip 5-volt
regulator, two error amplifiers, adjustable oscillator, dead­time control comparator, pulse-steering flip-flop, and
output-control circuitry. The uncommitted output
transistors pro-vide either common-emitter or emitter­follower output capability. Push-pull or single-ended
output operation may be selected through the output­control function. The ar-chitecture of the GL494 prohibits
the possibility of either output being pulsed twice during
push-pull operation.

Features

— Complete PWM Power Control Circuitry
— Uncommitted Outputs for 200mA Sink or Source
— Output Control Selects Single-Ended or Push-Pull

Operation

— Internal Circuitry Prohibits Double Pulse at Either

Output

— Internal Regulator Provides a Stable 5V Reference

Supply

— Variable Dead-Time Provides Control Over Total

Range

GL494

GL494

PWM CONTROL CIRCUIT

Pin Configuration

NONINV INPUT

INV. INPUT

FEEDBACK

DEAD TIME CONTROL

Cr

Rr

GND

C1

1
2
3
4
5
6
7
8

Function Table

Output Control Output Function
Grounded Single-ended or Parallel Output
At

V Normal Push-Pull Operation

ref

16

NON INV INPUT

15

INV. INPUT

14

REF. OUT

13

OUTPUT CONTROL

12

Vcc

11

C2

10

E2

9

E1

Block Diagram

DEAD

TIME

CONTROL

NONINVERTING(1)

INPUT

INVERTING (2)

INPUT

NONINVERTING(16)

INPUT

INVERTING (15)

INPUT

FEEDBACK

RT

CT

OSCILLATOR

0.1V

(4)

ERROR AMPLIFIERS

ERROR AMP1

ERROR AMP2

(3)

PWM

COMPARATOR

REFERENCE
REGULATOR

PULSE STEERING

(See Function Table)

FLIP FLOP

T

OUTPUT

CONTROL

(13)

Q

VCC
(12)

REF OUT
(14)

GND

(7)

E1(9) C1(8)

E1(10) C2(11)

2

Absolute Maximum Ratings

°

°

K

°

°

−

=

=

°

=

=

°

=

°−=

°

=

µ

=,Ω

=

=

°

=

µ

=,Ω

=

°−=

Supply Voltage,
Amplifier Input Voltage ………………………………………………………………..
Collector Output Voltage ……………………………………………………………………… 41 V
Continuous Total dissipation at (or below) 25C° ………………………………………. 1000 mW
Operating Free-Air Temperature Range ……………………………………………… -20 to 85
Storage Temperature Range ……………………………………………………….….. -65 to 150
Collector Output Current ………………………………………………………………….. 250 mA

V ……………………………………………………………………….. 41 V

CC

V +0.3 V

CC

Recommended Operation Conditions

PARAMETER MIN MAX UNIT

Supply Voltage,
Amplifier Input Voltage,

V 7 40 V

CC

V -0.3

1

V -2 V

CC

Collector Output Voltage, Vo 40 V
Collector Output Current

200 mA

(Each Transistor)
Current Into Feed back Terminal 0.3 mA
Timing Capacitor,
Timing Resistor,

C 0.47 10,000 nF

T

R 1.8 500 Ω

T

Oscillator Frequency 1 300 KHz
Operating Free-Air Temperature -20 85

Electrical Characteristics (Temperature

,

V =15V, f=10KHz)

C85~20

CC

Reference Section

PARAMETER TEST CONDITIONS MIN TYP(1) MAX UNIT

Output voltage (
Input regulation V7V
Output regulation 1I
Output Voltage change

with temperature
Short-circuit

Output current(2)

V ) mA1I

ref

O

CC

O

A

ref

4.75 5 5.25 V
to 40V, C25T

to 10mA, C25T

C20T

to

0V

35 mA

A

A

0.2 1 %

C85

2 25 mV

1 15 mV

GL494

C

C
C

Oscillator Section

PARAMETER TEST CONDITIONS MIN TYP(1) MAX UNIT

Frequency F01.0C
Standard deviation

of frequency (3)
Frequency change with

Voltage
Frequency change with

temperature

T

All values of

T,R,C Constant

ATT

V7V

CC

T

A

to 40V, C25T

F01.0C

C20T

to

T

V ,

CC

T

C85°

k12R

10 KHz

10 %

A

k12R

0.1 %

2 %

3

Dead Time Control Section

°

=

GL494

PARAMETER TEST CONDITIONS MIN TYP(1) MAX UNIT

Input bias current (pin 4) VI=0 to 5.25V -2 -10 Aµ
Maximum duty cycle,

Each output
Input threshold voltage

(pin 4)

V =0V 45 %

)4pin(I

Zero duty cycle 3 3.3 V
Maximum duty cycle 0 V

Error Amp Sections

Input offset voltage V5.2V
Input offset current V5.2V
Input bias current V5.2V
Common-mode input

voltage range
Open-loop voltage

Amplification
Unity-gain bandwidth 800 KHz
Common-mode rejection ratio

Output sink current (pin 3)

Output source current (pin 3)

PARAMETER TEST CONDITIONS MIN TYP(1) MAX UNIT

= 2 10 mV

)3PIN(O

= 25 250 nA

)3PIN(O

= 0.2 1 Aµ

)3PIN(O

5V

−= to –5V,

ID

V7VCC=

to 40V

==∆ to3.

OO

V40VCC= , C25T

A

mV15V

V7.0V

=

)3pin(O

mV15VID= to 5V,

V5.3V

=

)3pin(O

LOW

HIGH

5.0V,V3V

-0.3

2VCC−

70 95 dB

65 80 dB

0.3 0.7 mA

-2 mA

V

PWM Comparaor Section

Input threshold voltage (pin 3) Zero duty cycle 4 4.5 V
Input sink current (pin 3) V7.0V

PARAMETER TEST CONDITIONS MIN TYP(1) MAX UNIT

= 0.3 0.7 mA

)3pin(O

Switching Characteristics

PARAMETER TEST CONDITIONS MIN TYP(1) MAX UNIT

Output Voltage rise time 100 200 ns
Output Voltage fall time
Output Voltage rise time 100 200 ns
Output Voltage fall time

Common-emitter configuration,
See Test Circuit 3

Emitter-follower configuration,
See Test Circuit 4

25 100 ns

40 100 ns

4

Output Section

GL494

PARAMETER TEST CONDITIONS MIN TYP(1) MAX UNIT

Collector off-state current V40V,V40V
Emitter off-state current 0V,V40VV
Collector-emitter

Saturation voltage

Common-emitter

Emitter-follower

Output control input current

Total Device

PARAMETER TEST CONDITIONS MIN TYP(1) MAX UNIT

Standby supply current

Average supply current

Notes:

(1) All typical values except for temperature coefficients are at C25T
(2) Duration of the short circuit should not exceed one second.
(3) Standard deviation is a measure of the statistical distribution about the mean as derived from the formula

N

∑

1n

=

=σ

2

)XX(

−

n

1N

−

VV = 3.5 mA

refI

All other inputs &
Outputs open

V2V

=

)4pin(

See Test circuit 1

== 2 100 mA

CCCE

===

ECCC

mA200I,0V

== 1.1 1.3

CE

mA200I,V15V

−==

EC

V15VCC=

V40VCC=

-100 mA

1.5 2.5

6 10 mA
9 15 mA

7.5 mA

°=

A

V

5

Parameter Measurement Information

Vcc=15V

50kΩ

150Ω

150Ω
12kΩ

Vcc

Vcc

0

0

0%

0%

0V

0.7V

+

+

TEST CIRCUIT

VOLTAGE WAVEFORMS

1.Dead time and Feedback Control

TEST
INPUTS

DEAD TIME (4) (8) C1
FEEDBACK (3) (9) E1
Re (6)
Cr (5) (11) C2

0.01µF

(+) (16) ERROR (12) E2
(-) (15) AMP
(+) (1) ERROR
(-) (2) AMP

OUTPUT
CONTROL

(13)

(14) REF

GND (7)

OUT

2. Error Amplifier Characteristics

V1

ERROR AMPLIFIER
UNDER TEST

–

VREF

–

OTHER
ERROR
AMPLIFIER

3. Common-Emitter Configuration

(EACH OUTPUT

CIRCUIT)

15V

68Ω

2W

CL=15pF
(INCLUDES PROBE AND
JIG CAPACITANCE)

TEST CIRCUIT OUTPUT VOLTAGE WAVEFORM

2W

2W

OUTPUT

OUTPUT 1

OUTPUT 2

FEEDBACK
TERMINAL

VOLTAGE
AT C1

VOLTAGE
AT C2

VOLTAGE
AT CT

DEAD-TIME
CONTROL

INTPUT

FEEDBACK

DUTY
CYCLE

10%

THRESHOLD VOLTAGE

MAX

90%

90%

GL494

THRESHOLD VOLTAGE

MAX

10%

tf tr

6

4. Emitter-Follower Configuration

=15pF

(INCLUDES PROBE AND

JIG CAPACITANCE)

300k

1k 2k 5k 10k 20k 50k 100k 200k 500k 1M

1.0 10 100 1k 10k 100k 1M

AVOL, OPEN

LOOP VOATAGE GAIN (db)

100 1k 10k 100k

0 1.0 2.0 3.0 3.5

%DT. PERCENT DEADTIME, EACH OUTPUT

ACH OUTPUT

2 θ

(EACH OUTPUT

EIRCUIT)

15V

CL

TEST CIRCUIT OUTPUT VOLTAGE WAVEFORM

Typical Performance Curves

FIGURE 1 – OSCILLATOR FREQUENCY versus

100k

10k

1k

100

30

FIGURE 3 – PERCENT DEAD TIME
versus OSCILLATOR FREQUENCY

10

9

Vcc=15V

8

Voc=Vref

7

V(PIN4)=0V

6
5
4
3

2
1
0

TIMING RESISTANCE

0.001 µF

CT=0.01 µF

0.1 µF

0.1 µF

RT, TIMING RESISTANCE (Ω)

fo, OSCILLATOR FREQUENCY (Hz) DEAD TIME CONTROL VOLTAGE (V)

Vcc=15V

CT=0.01 µF

0.01 µF

68Ω
2W

OUTPUT

GL494

90%

10%

FIGURE 2 – OPEN LOOP VOLTAGE GAIN AND PHASE

100

90
80
70
60
50
40

30

-

20
10

0

FIGURE 4 – PERCENT DUTY CYCLE versus

50

40

30

20

10

DEAD-TIME CONTROL VOLTAGE

0

versus FREQUENCY

AVOL

f, FREQUENCY (Hz)

1

90%

10%

tf tr

Vcc=15V
Vo=3V
RL=2kΩ

Vcc=15V
Voc=Vref

1) CT=0.01
RT=10k

2) CT=0.001
RT=30K

20

0

-20

-40

-60

-80

-100

-120

-140

-160

-80

7

VCE(SAT), SATURATION VOLTAGE (V)

VCE(SAT), SATURATION VOLTAGE (V)

Icc, SUPPLY CURRENT (mA)

FIGURE 5 – EMITTER-FOLLOWER CONFIGURATION

1.9

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.1
0 50 100 150 200 250

FUGURE 7 – STANDBY-SUPPLY CURRENT

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0
0

0 5.0 10 15 20 25 30 35 40

OUTPUT-SATURATION VOLTAGE
versus EMITTER CURRENT

Vcc=15V

IE, EMITTER CURRENT (mA)

versus SUPPLY VOLTAGE

Vcc, SUPPLY VOLTAGE (V)

FIGURE 6 – COMMON-EMITTER CONFIGURATION

1.3

1.2

1.1

1.0

0.9

0.8

0.7

0.6

0.5
0 50 100 150 200 250

OUTPUT-SATURATION VOLTAGE
versus COLLECTOR CURRENT

Vcc=15V

Ic, COLLECTOR CURRENT (mA)

GL494