MC145027DWR2_技术文档

SEMICONDUCTOR TECHNICAL DATA

CMOS

These devices are designed to be used as encoder/decoder pairs in remote

control applications.

The MC145026 encodes nine lines of information and serially sends this

information upon receipt of a transmit enable (TE) signal. The nine lines may be

encoded with trinary data (low, high, or open) or binary data (low or high). The

words are transmitted twice per encoding sequence to increase security.

The MC145027 decoder receives the serial stream and interprets five of the

trinary digits as an address code. Thus, 243 addresses are possible. If binary

data is used at the encoder, 32 addresses are possible. The remaining serial

information is interpreted as four bits of binary data. The valid transmission (VT)

output goes high on the MC145027 when two conditions are met. First, two

addresses must be consecutively received (in one encoding sequence) which

both match the local address. Second, the 4 bits of data must match the last

valid data received. The active VT indicates that the information at the Data

output pins has been updated.

P SUFFIX

PLASTIC DIP

CASE 648

16

1

D SUFFIX

SOG PACKAGE

CASE 751B

16

The MC145028 decoder treats all nine trinary digits as an address which

allows 19,683 codes. If binary data is encoded, 512 codes are possible. The VT

output goes high on the MC145028 when two addresses are consecutively

received (in one encoding sequence) which both match the local address.

1

DW SUFFIX

SOG PACKAGE

CASE 751G

16

•

Operating Temperature Range: – 40 to + 85°C

Very–Low Standby Current for the Encoder: 300 nA Maximum @ 25°C

Interfaces with RF, Ultrasonic, or Infrared Modulators and Demodulators

RC Oscillator, No Crystal Required

High External Component Tolerance; Can Use ± 5% Components

Internal Power–On Reset Forces All Decoder Outputs Low

1

ORDERING INFORMATION

MC145026P

MC145026D

Plastic DIP

SOG Package

•

Operating Voltage Range: MC145026 = 2.5 to 18 V*

MC145027, MC145028 = 4.5 to 18 V

MC145027P

MC145027DW

Plastic DIP

SOG Package

•

For Infrared Applications, See Application Note AN1016/D

MC145028P

Plastic DIP

MC145028DW

SOG Package

PIN ASSIGNMENTS

MC145026

ENCODER

MC145027

DECODERS

MC145028

DECODERS

A1

A2

1

2

16

15

V

A1

A2

1

2

16

V

A1

A2

1

2

16

V

DD

D

out

15 D6

15 A6

A3

A4

3

4

14 TE

A3

A4

3

4

14 D7

13 D8

A3

A4

3

4

14 A7

13 A8

13

12

11

R

TC

A5

A6/D6

A7/D7

5

6

7

8

C

TC

A5

5

6

7

8

12 D9

11 VT

A5

5

6

7

8

12 A9

11 VT

R

S

R

1

R

1

10 A9/D9

C

1

10 R /C

C

1

10 R /C

2 2

2

V

SS

9

V

SS

9

V

SS

9

A8/D8

D

in

D

in

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

MC145026 MC145027 MC145028

3.2–263

R

S

R

TC

C

TC

11

14

12

3–PIN

OSCILLATOR

AND

13

TE

DATA SELECT

AND

BUFFER

÷ 4

DIVIDER

15

D

out

ENABLE

RING COUNTER AND 1–OF–9 DECODER

9

8

7

6

5

4

3

2

1

2

A1

A2

A3

A4

A5

3

4

5

TRINARY

DETECTOR

6

A6/D6

A7/D7

A8/D8

A9/D9

7

9

V

SS

= PIN 16

= PIN 8

DD

10

Figure 1. MC145026 Encoder Block Diagram

11

15

VT

D6

D7

CONTROL

LOGIC

14

13

D8

D9

12

SEQUENCER CIRCUIT

5

4

3

2

1

2

3

4

5

A1

A2

A3

A4

A5

DATA

EXTRACTOR

9

D

in

C

1

C

2

V

= PIN 16

= PIN 8

DD

7

6

10

V

SS

R

1

R

2

Figure 2. MC145027 Decoder Block Diagram

MC145026 MC145027 MC145028

3.2–264

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

11

CONTROL

LOGIC

VT

SEQUENCER CIRCUIT

9

8

7

6

5

4

3

2

1

2

A1

A2

A3

A4

A5

A6

A7

A8

A9

9–BIT

SHIFT

REGISTER

3

4

DATA

EXTRACTOR

5

9

D

in

15

14

13

12

C

1

C

2

7

6

V

= PIN 16

= PIN 8

10

DD

V

R

1

SS

R

2

Figure 3. MC145028 Decoder Block Diagram

MAXIMUM RATINGS* (Voltages Referenced to V

)

SS

This device contains protection circuitry to

guard against damage due to high static

voltages or electric fields. However, precau-

tionsmustbetakentoavoidapplicationsofany

voltage higher than maximum rated voltages

to this high–impedance circuit. For proper

Rating

Symbol

Value

Unit

V

DD

DC Supply Voltage (except SC41343,

SC41344)

– 0.5 to + 18

V

DD

DC Supply Voltage (SC41343, SC41344

only)

– 0.5 to + 10

V

operation, V and V

should be constrained

in out

to the range V

≤ (V or V ) ≤ V

.

V

in

DC Input Voltage

– 0.5 to V

+ 0.5

V

SS in out DD

DD

V

out

DC Output Voltage

– 0.5 to V

+ 0.5

DD

I

DC Input Current, per Pin

DC Output Current, per Pin

Power Dissipation, per Package

Storage Temperature

± 10

mA

mW

°C

in

I

± 10

out

P

500

D

T

stg

– 65 to + 150

260

T

Lead Temperature, 1 mm from Case for

10 Seconds

°C

L

* MaximumRatingsarethosevaluesbeyondwhichdamagetothedevicemayoccur. Func-

tional operation should be restricted to the limits in the Electrical Characteristics tables or

Pin Descriptions section.

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

MC145026 MC145027 MC145028

3.2–265

ELECTRICAL CHARACTERISTICS — MC145026*, MC145027, and MC145028 (Voltage Referenced to V

)

SS

Guaranteed Limit

– 40°C

25°C

85°C

V

DD

V

Symbol

Characteristic

Low–Level Output Voltage

Unit

Min

Max

Min

Max

Min

Max

V

OL

(V = V

in

or 0)

DD

5.0

10

15

—

0.05

—

0.05

—

0.05

V

High–Level Output Voltage

Low–Level Input Voltage

(V = 0 or V

in

)

DD

5.0

10

15

4.95

9.95

14.95

—

4.95

9.95

14.95

—

4.95

9.95

14.95

—

V

OH

V

IL

(V

= 4.5 or 0.5 V)

= 9.0 or 1.0 V)

= 13.5 or 1.5 V)

5.0

10

15

—

1.5

3.0

4.0

—

1.5

3.0

4.0

—

1.5

3.0

4.0

out

(V

out

V

High–Level Input Voltage

High–Level Output Current

V

IH

(V

= 0.5 or 4.5 V)

= 1.0 or 9.0 V)

= 1.5 or 13.5 V)

5.0

10

15

3.5

7.0

11

—

3.5

7.0

11

—

3.5

7.0

11

—

out

(V

out

(V

out

I

mA

OH

(V

out

= 2.5 V)

= 4.6 V)

= 9.5 V)

5.0

10

– 2.5

– 0.52

– 1.3

– 3.6

—

– 2.1

– 0.44

– 1.1

– 3.0

—

– 1.7

– 0.36

– 0.9

– 2.4

—

(V

out

= 13.5 V)

15

I

Low–Level Output Current

mA

OL

(V

out

(V

out

= 0.4 V)

= 0.5 V)

= 1.5 V)

5.0

10

15

0.52

1.3

3.6

—

0.44

1.1

3.0

—

0.36

0.9

2.4

—

(V

I

in

Input Current — TE

(MC145026, Pull–Up Device)

5.0

10

15

—

3.0

16

35

11

60

120

—

µA

I

Input Current

15

—

± 0.3

—

± 0.3

—

± 1.0

µA

in

R

(MC145026), D (MC145027, MC145028)

in

S

Input Current

in

A1 – A5, A6/D6 – A9/D9 (MC145026),

A1 – A5 (MC145027),

A1 – A9 (MC145028)

5.0

10

15

—

± 110

± 500

± 1000

—

C

Input Capacitance (V = 0)

in

—

7.5

—

pF

in

I

Quiescent Current — MC145026

5.0

10

15

—

0.1

0.2

0.3

—

µA

DD

I

Quiescent Current — MC145027, MC145028

Dynamic Supply Current — MC145026

5.0

10

15

—

50

100

150

—

µA

DD

I

5.0

10

15

—

200

400

600

—

dd

(f = 20 kHz)

c

I

Dynamic Supply Current — MC145027, MC145028

(f = 20 kHz)

c

5.0

10

15

—

400

800

1200

—

dd

* Also see next Electrical Characteristics table for 2.5 V specifications.

MC145026 MC145027 MC145028

3.2–266

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

ELECTRICAL CHARACTERISTICS — MC145026 (Voltage Referenced to V

)

SS

Guaranteed Limit

– 40°C

Min

25°C

85°C

V

DD

V

Symbol

Characteristic

Low–Level Output Voltage (V = 0 V or V

Unit

V

Max

0.05

—

Min

—

Max

0.05

—

Min

—

Max

0.05

—

V

OL

)

2.5

—

2.45

—

in

(V = 0 V or V

DD

V

OH

High–Level Output Voltage

Low–Level Input Voltage

High–Level Input Voltage

High–Level Output Current

Low–Level Output Current

2.45

—

2.45

—

V

in

V

(V

out

= 0.5 V or 2.0 V)

0.3

—

0.3

—

0.3

—

V

IL

IH

V

(V

out

2.2

0.28

0.22

—

2.2

0.25

0.2

0.09

—

2.2

0.2

0.16

—

V

I

(V

out

= 1.25 V)

= 0.4 V)

—

mA

µA

OH

I

(V

out

—

OL

I

Input Current (TE — Pull–Up Device)

Input Current (A1–A5, A6/D6–A9/D9)

Quiescent Current

—

1.8

± 25

0.05

40

—

in

I

—

I

—

DD

I

dd

Dynamic Supply Current (f = 20 kHz)

—

c

SWITCHING CHARACTERISTICS — MC145026*, MC145027, and MC145028 (C = 50 pF, T = 25°C)

L

A

Guaranteed Limit

Figure

No.

Symbol

, t

Characteristic

Output Transition Time

V

DD

Unit

Min

Max

t

4,8

5.0

10

15

—

200

100

80

ns

TLH THL

t

D

Rise Time — Decoders

5

5.0

10

15

—

15

µs

r

in

t

Fall Time — Decoders

5

5.0

10

15

—

15

5.0

4.0

f

Encoder Clock Frequency

6

5.0

10

15

0.001

2.0

5.0

10

MHz

kHz

ns

osc

f

Decoder Frequency — Referenced to Encoder Clock

TE Pulse Width — Encoders

12

7

5.0

10

15

1.0

240

410

450

t

w

5.0

10

15

65

30

20

—

* Also see next Switching Characteristics table for 2.5 V specifications.

SWITCHING CHARACTERISTICS — MC145026 (C = 50 pF, T = 25°C)

L

A

Guaranteed Limit

Figure

No.

Symbol

, t

Characteristic

Output Transition Time

V

Unit

ns

Min

—

Max

450

250

—

DD

t

4, 8

6

2.5

TLH THL

f

Encoder Clock Frequency

TE Pulse Width

2.5

1.0

1.5

kHz

µs

osc

t

w

7

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

MC145026 MC145027 MC145028

3.2–267

90%

10%

t

f

t

r

ANY OUTPUT

V

DD

90%

D

in

t

TLH

THL

10%

V

SS

Figure 4.

Figure 5.

1/f

osc

V

DD

TE

50%

R

TC

V

SS

t

w

Figure 6.

Figure 7.

TEST POINT

OUTPUT

DEVICE

UNDER

TEST

C *

L

* Includes all probe and fixture capacitance.

Figure 8. Test Circuit

MC145026 MC145027 MC145028

3.2–268

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

MC145028

OPERATING CHARACTERISTICS

This decoder operates in the same manner as the

MC145027 except that nine address lines are used and no

data output is available. The VT output is used to indicate

that a valid address has been received. For transmission

security, two identical transmitted words must be con-

secutively received before a VT output signal is issued.

The MC145028 allows 19,683 addresses when trinary lev-

els are used. 512 addresses are possible when binary levels

are used.

MC145026

The encoder serially transmits trinary data as defined by

the state of the A1 – A5 and A6/D6 – A9/D9 input pins. These

pins may be in either of three states (low, high, or open)

allowing 19,683 possible codes. The transmit sequence is

initiated by a low level on the TE input pin. Upon power–up,

the MC145026 can continuously transmit as long as TE

remains low (also, the device can transmit two–word

sequences by pulsing TE low). However, no MC145026

application should be designed to rely upon the first data

word transmitted immediately after power–up because this

word may be invalid. Between the two data words, no signal

is sent for three data periods (see Figure 10).

PIN DESCRIPTIONS

MC145026 ENCODER

A1 – A5, A6/D6 – A9/D9

Address, Address/Data Inputs (Pins 1 – 7, 9, and 10)

These address/data inputs are encoded and the data is

Each transmitted trinary digit is encoded into pulses (see

Figure 11). A logic 0 (low) is encoded as two consecutive

short pulses, a logic 1 (high) as two consecutive long pulses,

and an open (high impedance) as a long pulse followed by a

short pulse. The input state is determined by using a weak

“output” device to try to force each input high then low. If only

a high state results from the two tests, the input is assumed

sent serially from the encoder via the D

pin.

out

R , C , R

S

TC TC

(Pins 11, 12, and 13)

These pins are part of the oscillator section of the encoder

(see Figure 9).

to be hardwired to V . If only a low state is obtained, the

If an external signal source is used instead of the internal

DD

input is assumed to be hardwired to V . If both a high and a

oscillator, it should be connected to the R input and the R

SS

S TC

low can be forced at an input, an open is assumed and is

encoded as such. The “high” and “low” levels are 70% and

30% of the supply voltage as shown in the Electrical Charac-

teristics table. The weak “output” device sinks/sources up to

110 µA at a 5 V supply level, 500 µA at 10 V, and 1 mA at

15 V.

and C

pins should be left open.

TC

TE

Transmit Enable (Pin 14)

This active–low transmit enable input initiates transmis-

sion when forced low. An internal pull–up device keeps this

input normally high. The pull–up current is specified in the

Electrical Characteristics table.

The TE input has an internal pull–up device so that a sim-

ple switch may be used to force the input low. While TE is

high and the second–word transmission has timed out, the

encoder is completely disabled, the oscillator is inhibited,

and the current drain is reduced to quiescent current. When

TE is brought low, the oscillator is started and the transmit

sequence begins. The inputs are then sequentially selected,

and determinations are made as to the input logic states.

D

out

Data Out (Pin 15)

This is the output of the encoder that serially presents the

encoded data word.

This information is serially transmitted via the D

pin.

V

SS

out

Negative Power Supply (Pin 8)

The most–negative supply potential. This pin is usually

ground.

MC145027

This decoder receives the serial data from the encoder

and outputs the data, if it is valid. The transmitted data, con-

sisting of two identical words, is examined bit by bit during

reception. The first five trinary digits are assumed to be the

address. If the received address matches the local address,

the next four (data) bits are internally stored, but are not

transferred to the output data latch. As the second encoded

word is received, the address must again match. If a match

occurs, the new data bits are checked against the previously

stored data bits. If the two nibbles of data (four bits each)

match, the data is transferred to the output data latch by VT

and remains until new data replaces it. At the same time, the

VT output pin is brought high and remains high until an error

is received or until no input signal is received for four data

periods (see Figure 10).

V

DD

Positive Power Supply (Pin 16)

The most–positive power supply pin.

MC145027 AND MC145028 DECODERS

A1 – A5, A1 – A9

Address Inputs (Pins 1 – 5) — MC145027,

Address Inputs (Pins 1 – 5, 15, 14, 13, 12) — MC145028

These are the local address inputs. The states of these

pins must match the appropriate encoder inputs for the VT

pin to go high. The local address may be encoded with tri-

nary or binary data.

D6 – D9

Data Outputs (Pins 15, 14, 13, 12) — MC145027 Only

Although the address information may be encoded in tri-

nary, the data information must be either a 1 or 0. A trinary

(open) data line is decoded as a logic 1.

These outputs present the binary information that is on

encoder inputs A6/D6 through A9/D9. Only binary data is

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

MC145026 MC145027 MC145028

3.2–269

acknowledged; a trinary open at the MC145026 encoder is

decoded as a high level (logic 1).

constant is used to determine whether the D pin has

in

remained low for four data periods (end of transmission). A

separate on–chip comparator looks at the voltage–equiva-

lent two data periods (0.4 R C ) to detect the dead time be-

D

in

2

Data In (Pin 9)

tween received words within a transmission.

This pin is the serial data input to the decoder. The input

voltage must be at CMOS logic levels. The signal source

driving this pin must be dc coupled.

VT

Valid Transmission Output (Pin 11)

This valid transmission output goes high after the second

word of an encoding sequence when the following conditions

are satisfied:

R , C

1

Resistor 1, Capacitor 1 (Pins 6, 7)

1. thereceivedaddressesofbothwordsmatchthelocalde-

coder address, and

2. the received data bits of both words match.

As shown in Figures 2 and 3, these pins accept a resistor

and capacitor that are used to determine whether a narrow

pulse or wide pulse has been received. The time constant

VT remains high until either a mismatch is received or no

input signal is received for four data periods.

R x C should be set to 1.72 encoder clock periods:

1

R C = 3.95 R

C

1

TC TC

V

SS

Negative Power Supply (Pin 8)

R /C

2

Resistor 2/Capacitor 2 (Pin 10)

The most–negative supply potential. This pin is usually

ground.

As shown in Figures 2 and 3, this pin accepts a resistor

and capacitor that are used to detect both the end of a

received word and the end of a transmission. The time

V

DD

Positive Power Supply (Pin 16)

constant R x C should be 33.5 encoder clock periods (four

2

data periods per Figure 11): R C = 77 R

C

. This time

The most–positive power supply pin.

2

TC TC

MC145026 MC145027 MC145028

3.2–270

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

R

S

C

TC

R

TC

11

12

13

INTERNAL

ENABLE

This oscillator operates at a frequency determined by the

external RC network; i.e.,

1

f ≈

(Hz)

ThevalueforR shouldbechosentobe≥ 2timesR .Thisrangeensures

S TC

2.3 R ′

C

TC TC

thatcurrentthroughR isinsignificantcomparedtocurrentthroughR . The

S

TC

upperlimitforR mustensurethatR x5pF(inputcapacitance)issmallcom-

S

for 1 kHz ≤ f ≤ 400 kHz

where: C ′ = C + C + 12 pF

pared to R

TC

x C

.

TC

layout

For frequencies outside the indicated range, the formula is less accurate.

Theminimumrecommendedoscillationfrequencyofthiscircuitis1kHz. Sus-

ceptibilitytoexternallyinducednoisesignalsmayoccurforfrequenciesbelow

1 kHz and/or when resistors utilized are greater than 1 MΩ.

R

≈ 2 R

S

TC

≥ 20 k

≥ 10 k

TC

400 pF < C

< 15 µF

TC

Figure 9. Encoder Oscillator Information

ENCODER

PW

min

2 WORD TRANSMISSION

TE

CONTINUOUS TRANSMISSION

ENCODER

OSCILLATOR

(PIN 12)

1ST

DIGIT

9TH

DIGIT

1ST

DIGIT

9TH

DIGIT

D

out

(PIN 15)

OPEN

LOW

HIGH

1ST WORD

2ND WORD

ENCODING SEQUENCE

1.1 (R C )

2 2

DECODER

VT

(PIN 11)

DATA OUTPUTS

Figure 10. Timing Diagram

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

MC145026 MC145027 MC145028

3.2–271

ENCODER

OSCILLATOR

(PIN 12)

ENCODED

“ONE”

D

ENCODED

“ZERO”

out

(PIN 15)

ENCODED

“OPEN”

DATA PERIOD

Figure 11. Encoder Data Waveforms

500

400

300

V

= 15 V

DD

V

= 10 V

DD

200

100

V

DD

= 5 V

10

20

30

40

50

C

layout

(pF) ON PINS 1 – 5 (MC145027); PINS 1 – 5 AND 12 – 15 (MC145028)

Figure 12. f

max

vs C — Decoders Only

layout

MC145026 MC145027 MC145028

3.2–272

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

HAS

NO

THE TRANSMISSION

BEGUN?

YES

DOES

THE 5–BIT

ADDRESS MATCH

THE ADDRESS

PINS?

DISABLE VT

ON THE 1ST

ADDRESS MISMATCH

NO

YES

STORE

THE

4–BIT

DATA

DOES

THIS DATA

MATCH THE PREVIOUSLY

STORED

DISABLE VT

ON THE 1ST

DATA MISMATCH

NO

DATA?

YES

IS THIS

AT LEAST THE

2ND CONSECUTIVE

MATCH SINCE VT

DISABLE?

YES

LATCH DATA

ONTO OUTPUT

PINS AND

ACTIVATE VT

HAVE

4–BIT TIMES

PASSED?

YES

DISABLE

VT

NO

HAS

A NEW

NO

TRANSMISSION

BEGUN?

YES

Figure 13. MC145027 Flowchart

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

MC145026 MC145027 MC145028

3.2–273

HAS

NO

THE TRANSMISSION

BEGUN?

YES

DOES

THE ADDRESS

MATCH THE

ADDRESS

PINS?

DISABLE VT ON THE 1ST

ADDRESS MISMATCH

AND IGNORE THE REST

OF THIS WORD

NO

YES

IS

THIS AT LEAST

THE 2ND CONSECUTIVE

MATCH SINCE VT

DISABLE?

NO

YES

ACTIVATE VT

HAVE

4–BIT TIMES

PASSED?

YES

DISABLE VT

NO

HAS A

NEW TRANSMISSION

BEGUN?

NO

YES

Figure 14. MC145028 Flowchart

MC145026 MC145027 MC145028

3.2–274

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

V

DD

MC145027 AND MC145028 TIMING

D

in

To verify the MC145027 or MC145028 timing, check the

waveforms on C1 (Pin 7) and R2/C2 (Pin 10) as compared to

0 V

the incoming data waveform on D (Pin 9).

The R–C decay seen on C1 discharges down to 1/3 V

in

DD

V

DD

2/3

1/3

0 V

before being reset to V . This point of reset (labelled “DOS”

DD

in Figure 15) is the point in time where the decision is made

C1

whether the data seen on D is a 1 or 0. DOS should not be

in

too close to the D data edges or intermittent operation may

in

DOS

occur.

The other timing to be checked on the MC145027 and

MC145028 is on R2/C2 (see Figure 16). The R–C decay is

Figure 15. R–C Decay on Pin 7 (C1)

continually reset to V

as data is being transmitted. Only

between words and after the end–of–transmission (EOT)

DD

does R2/C2 decay significantly from V . R2/C2 can be

DD

used to identify the internal end–of–word (EOW) timing edge

which is generated when R2/C2 decays to 2/3 V . The in-

ternal EOT timing edge occurs when R2/C2 decays to 1/3

DD

EOW

V

DD

V

. When the waveform is being observed, the R–C decay

DD

should go down between the 2/3 and 1/3 V

2/3

1/3

0 V

levels, but not

DD

R2/C2

too close to either level before data transmission on D re-

sumes.

in

Verification of the timing described above should ensure a

good match between the MC145026 transmitter and the

MC145027 and MC145028 receivers.

EOT

Figure 16. R–C Decay on Pin 10 (R2/C2)

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

MC145026 MC145027 MC145028

3.2–275

V

DD

V

DD

V

DD

TE

V

DD

0.1 µF

A1

14

16

A2

A3

A4

A5

D6

D7

D8

D9

5

A2

A3

15

D

in

9

6

1

2

3

out

1

2

TRINARY

ADDRESSES

5

TRINARY

ADDRESSES

3

4

A4

A5

4

R1

7

5

6

7

9

5

15

14

MC145026

MC145027

R

TC

13

12

C

1

D6

D7

D8

D9

C

TC

4–BIT

BINARY

DATA

13

12

11

10

11

10

R

S

VT

C

2

8

R2

8

C

′ = C

+ C

+ 12 pF

layout

TC

100 pF ≤ C

1

≤ 15 µF

TC

≥ 10 kΩ; R ≈ 2 R

TC

REPEAT OF ABOVE

f

=

osc

R

C

R

C

2.3 R ′

C

TC

S

TC TC

≥ 10 kΩ

1

2

≥ 400 pF

≥ 100 kΩ

≥ 700 pF

R C = 3.95 R

1 1

C

TC TC

C

TC TC

R C = 77 R

2 2

Example R/C Values (All Resistors and Capacitors are ± 5%)

(C ′ = C

TC

+ 20 pF)

TC

(kHz)

f

R

C

R

C

R

C

2

osc

362

TC

TC′

S

1

2

10 k

50 k

120 pF

240 pF

490 pF

1020 pF

2020 pF

5100 pF

20 k

100 k

10 k

50 k

470 pF

910 pF

100 k

200 k

910 pF

1800 pF

3900 pF

7500 pF

0.015 µF

0.02 µF

0.1 µF

181

88.7

42.6

21.5

8.53

1.71

2000 pF

3900 pF

8200 pF

0.02 µF

Figure 17. Typical Application

MC145026 MC145027 MC145028

3.2–276

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

detected and filtered by a diode/RC network to extract the

data envelope from the burst. Comparator A5 boosts the sig-

nal to logic levels compatible with the MC145027/28 data

APPLICATIONS INFORMATION

INFRARED TRANSMITTER

input. The D pin of these decoders is a standard CMOS

in

In Figure 18, the MC145026 encoder is set to run at an os-

cillator frequency of about 4 to 9 kHz. Thus, the time required

for a complete two–word encoding sequence is about 20 to

40 ms. The data output from the encoder gates an RC oscil-

lator running at 50 kHz; the oscillator shown starts rapidly

enough to be used in this application. When the “send” but-

ton is not depressed, both the MC145026 and oscillator are

in a low–power standby state. The RC oscillator has to be

trimmed for 50 kHz and has some drawbacks for frequency

stability. A superior system uses a ceramic resonator oscilla-

tor running at 400 kHz. This oscillator feeds a divider as

shown in Figure 19. The unused inputs of the MC14011UB

must be grounded.

The MLED81 IRED is driven with the 50 kHz square wave

at about 200 to 300 mA to generate the carrier. If desired, two

IREDs wired in series can be used (see Application Note

AN1016 for more information). The bipolar IRED switch,

shown in Figure 18, offers two advantages over a FET. First,

a logic FET has too much gate capacitance for the

MC14011UB to drive without waveform distortion. Second,

the bipolar drive permits lower supply voltages, which are an

advantage in portable battery–powered applications.

The configuration shown in Figure 18 operates over a

supply range of 4.5 to 18 V. A low–voltage system which

operates down to 2.5 V could be realized if the oscillator sec-

tion of a MC74HC4060 is used in place of the MC14011UB.

The data output of the MC145026 is inverted and fed to the

RESET pin of the MC74HC4060. Alternately, the

MC74HCU04 could be used for the oscillator.

high–impedance input which must not be allowed to float.

Therefore, direct coupling from A5 to the decoder input is

utilized.

Shielding should be used on at least A1 and A2, with good

ground and high–sensitivity circuit layout techniques applied.

For operation with supplies higher than + 5 V, limiter A4’s

positive output swing needs to be limited to 3 to 5 V. This is

accomplished via adding a zener diode in the negative feed-

back path, thus avoiding excessive system noise. The bias-

ing resistor stack should be adjusted such that V3 is 1.25 to

1.5 V.

This system works up to a range of about 10 meters. The

gains of the system may be adjusted to suit the individual

design needs. The 100 Ω resistor in the emitter of the first

2N5088 and the 1 kΩ resistor feeding A2 may be altered if

different gain is required. In general, more gain does not nec-

essarily result in increased range. This is due to noise floor

limitations. The designer should increase transmitter power

and/or increase receiver aperature with Fresnal lensing to

greatly improve range. See Application Note AN1016 for

additional information.

Information on the MC34074 is in data book DL128/D.

TRINARY SWITCH MANUFACTURERS

Midland Ross–Electronic Connector Div.

Greyhill

Augat/Alcoswitch

Aries Electronics

Information on the MC14011UB is in book number

DL131/D. The MC74HCU04 and MC74HC4060 are found in

book number DL129/D.

The above companies may not have the switches in a DIP.

For more information, call them or consult eem Electronic

Engineers Master Catalog or the Gold Book. Ask for SPDT

with center OFF.

INFRARED RECEIVER

The receiver in Figure 20 couples an IR–sensitive diode to

input preamp A1, followed by band–pass amplifier A2 with a

gain of about 10. Limiting stage A3 follows, with an output of

about 800 mV p–p. The limited 50 kHz burst is detected by

comparator A4 that passes only positive pulses, and peak–

Alternative: An SPST can be placed in series between a

SPDT and the Encoder or Decoder to achieve trinary action.

Motorola cannot recommend one supplier over another

and in no way suggests that this is a complete listing of tri-

nary switch manufacturers.

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

MC145026 MC145027 MC145028

3.2–277

V+

SELECT FOR

200 mA TO 300 mA

USE OF 2 MLED81s

IS OPTIONAL

MLED81

MC14011UB

10 kΩ

MPSA13

OR

SEND

MPSW13

MC14011UB

TE

D

out

MC145026

R

S

C

TC

R

TC

0.01 µF

220 kΩ

1000 pF

9

ADJUST/SELECT FOR

f = 50 kHz (APPROX. 100 kΩ)

SWITCHES

220 kΩ

100 kΩ FOR APPROX. 4 kHz

47 kΩ FOR APPROX. 9 kHz

Figure 18. IRED Transmitter Using RC Oscillator to Generate Carrier Frequency

V+

MC14011UB

MC14024

50 kHZ TO

CLK

Q3

DRIVER

TRANSISTOR

RESET

1MΩ

X1 = 400 kHz CERAMIC RESONATOR

PANASONIC EFD–A400K04B

OR EQUIVALENT

V+

MC14011UB

X1

D

out

FROM MC145026

470 pF

Figure 19. Using a Ceramic Resonator to Generate Carrier Frequency

MC145026 MC145027 MC145028

3.2–278

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

+5 V

10 kΩ

A1

1 mH — TOKO TYPE 7PA OR 10PA

OR EQUIVALENT

10 µF

10 kΩ

10 µF

22 kΩ

0.01 µF

2N5088

2N5086

2N5088

10 kΩ

0.01 µF

1 kΩ

–

A2

+

V1

100 Ω

1 µF

6.8 kΩ

2.2 kΩ

OPTICAL

FILTER

1/4 MC34074

1N914

4.7 kΩ

0.01 µF

1 MΩ

100 kΩ

1 MΩ

–

10 kΩ

1N914

A3

+

1 kΩ

22 kΩ

V1

+

A4

–

V2

A5

1/4 MC34074

V3

–

1/4 MC34074

1000 pF

47 kΩ

1/4 MC34074

+5 V

390 kΩ FOR APPROX. 4 kHz

180 kΩ FOR APPROX. 9 kHz

1000 pF

750 kΩ FOR APPROX. 4 kHz

360 kΩ FOR APPROX. 9 kHz

0.01 µF

4.7 kΩ

390 Ω

V2 ≈ 2.7 V

V1 ≈ 2.5 V

R1

R2/C2

VT

C1

MC145027/28

D

in

2.2 kΩ

2.7 kΩ

DATA OUT

MC145027 ONLY

V

DD

V

SS

4

10 µF

V3 ≈ 1.3 V

10 µF

9 FOR MC145027

5 FOR MC145028

10 µF

+5 V

ADDRESS

SWITCHES

Figure 20. Infrared Receiver

MOTOROLA WIRELESS RF, IF AND TRANSMITTER DEVICE DATA

MC145026 MC145027 MC145028

3.2–279


型号：	MC145027DWR2
厂家：	MOTOROLA
描述：	SPECIALTY CONSUMER CIRCUIT, PDSO16, SOG-16 光电二极管商用集成电路
文件：	总17页 (文件大小：124K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

MC145027DWR2 [MOTOROLA]

相关型号：

MC145027P

MC145027P

MC145027P

MC145027P

MC145028

MC145028

MC145028D

MC145028DW

MC145028DW

MC145028DW

MC145028DW

MC145028DWR2