SA614AHRX_技术文档

SA614A

Low power FM IF system

Rev. 4 — 14 February 2014

Product data sheet

1. General description

The SA614A is an improved monolithic low-power FM IF system. It incorporates two

limiting intermediate frequency amplifiers, quadrature detector, muting, logarithmic

received signal strength indicator, and voltage regulator. The SA614A features higher IF

bandwidth (25 MHz) and temperature compensated RSSI and limiters permitting higher

performance application compared with the SA604. The SA614A is available in a SO

(surface-mounted miniature) package.

2. Features and benefits

 Low power consumption: 3.3 mA typical

 Temperature compensated logarithmic RSSI with a 90 dB dynamic range

 Two audio outputs - muted and unmuted

 Low external component count; suitable for crystal/ceramic filters

 Excellent sensitivity: 1.5 V across inputs pins (0.22 V into 50  matching network)

for 12 dB SINAD (SIgnal-to-Noise-And-Distortion ratio) for 1 kHz tone with RF at

45 MHz and IF at 455 kHz

 SA614A meets cellular radio specifications

3. Applications

 Cellular radio FM IF

 High performance communication receiver

 Intermediate frequency amplification and detection up to 25 MHz

 RF level meter

 Spectrum analyzer

 Instrumentation

 FSK and ASK data receivers

4. Ordering information

Table 1.

Ordering information

T_amb= 40 C to +85 C

Type number

Package

Name

Description

Version

SA614AD

SO16

plastic small outline package; 16 leads; body width 3.9 mm

SOT109-1

SOT1039-2

SA614AHR

HXQFN16

plastic thermal enhanced extremely thin quad flat package; no leads;

16 terminals; body 3  3  0.5 mm

SA614A

NXP Semiconductors

Low power FM IF system

5. Block diagram

GND

16 (13) 15 (12) 14 (11) 13 (10) 12 (9)

11 (8)

10 (7)

9 (6)

LIMITER

IF

AMP

QUAD

DET

SIGNAL

STRENGTH

VOLTAGE

MUTE

6 (3)

REGULATOR

1 (14)

2 (15)

GND

3 (16)

4 (1)

5 (2)

7 (4)

8 (5)

V

CC

aaa-009746

Pin numbers for SO16; HXQFN16 pins shown in parentheses.

Fig 1. Block diagram of SA614A

SA614A

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Product data sheet

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SA614A

NXP Semiconductors

Low power FM IF system

6. Pinning information

6.1 Pinning

1

2

3

4

5

6

7

8

16

15

14

13

12

11

10

9

IF_AMP_DECOUPL

GND

IF_AMP_INPUT

IF_AMP_DECOUPL

IF_AMP_OUTPUT

GND

MUTE_INPUT

V

CC

SA614A

RSSI_OUTPUT

MUTE_AUD_OUTP

LIMITER_INPUT

LIMITER_DECOUPL

LIMITER_OUTPUT

UNMUTE_AUD_OUTP

QUADRATURE_INPUT

aaa-009743

Fig 2. Pin configuration for SO16

terminal 1

index area

1

2

3

4

12

11

10

9

V

IF_AMP_DECOUPL

IF_AMP_OUTPUT

GND

CC

RRSI_OUTP

MUTE_AUD_OUTP

SA614A

(1)

UNMUTE_AUD_OUTP

LIMITER_INPUT

aaa-009745

Transparent top view

(1) Die Attach Paddle (DAP).

Fig 3. Pin configuration for HXQFN16

SA614A

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Product data sheet

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SA614A

NXP Semiconductors

Low power FM IF system

6.2 Pin description

Table 2.

Symbol

Pin description

SO16

1

Description

HXQFN16

IF_AMP_DECOUPL

GND

14

15

16

1

IF amplifier decoupling

ground

2

MUTE_INPUT

V_CC

3

mute input

4

supply voltage

RSSI_OUTPUT

MUTE_AUD_OUTP

UNMUTE_AUD_OUTP

QUADRATURE_INPUT

LIMITER_OUTPUT

LIMITER_DECOUPL

LIMITER_INPUT

GND

5

2

RSSI output

6

3

mute audio output

unmute audio output

quadrature input

limiter output

7

4

8

5

9

6

10

11

12

13

14

15

16

-

7

limiter decoupling

limiter input

8

9

10^[1]

11

12

13

DAP

ground

IF_AMP_OUTPUT

IF_AMP_DECOUPL

IF_AMP_INPUT

-

IF amplifier output

IF amplifier decoupling

IF amplifier input

exposed Die Attach Paddle

[1] HXQFN16 package supply ground is connected to both GND pin and exposed center pad. GND pin must

be connected to supply ground for proper device operation. For enhanced thermal, electrical, and board

level performance, the exposed pad must be soldered to the board using a corresponding thermal pad on

the board. For proper heat conduction through the board, thermal vias must be incorporated in the PCB in

the thermal pad region.

SA614A

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Product data sheet

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SA614A

NXP Semiconductors

Low power FM IF system

8. Limiting values

Table 3.

Limiting values

In accordance with the Absolute Maximum Rating System (IEC 60134).

Symbol

V_CC

Parameter

Conditions

Min

-

Max

9

Unit

V

supply voltage

T_stg

storage temperature

ambient temperature

65

40

+150

+85

C

T_amb

operating

9. Thermal characteristics

Table 4.

Symbol

Z_th(j-a)

Thermal characteristics

Parameter

Conditions

SA614AD (SO16)

SA614AHR (HXQFN16)

Max

Unit

K/W

transient thermal impedance

from junction to ambient

90

75

10. Static characteristics

Table 5.

Static characteristics

V_CC= 3 V; T_amb= 25 C; unless specified otherwise.

Symbol

I_CC

Parameter

Conditions

Min

2.5

4.5

1.7

-

Typ

Max

4.0

8.0

-

Unit

mA

V

supply current

supply voltage

threshold voltage

3.3

V_CC

-

V_th

mute switch-on

mute switch-off

V

1.0

V

SA614A

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Product data sheet

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SA614A

NXP Semiconductors

Low power FM IF system

11. Dynamic characteristics

Table 6.

Dynamic characteristics

T_amb= 25 C; V_CC= 6 V; unless specified otherwise. IF frequency = 455 kHz; IF level = 47 dBm; FM modulation = 1 kHz

with 8 kHz peak deviation. Audio output with de-emphasis filter and C-message weighted filter. Test circuit Figure 14. The

parameters listed below are tested using automatic test equipment to assure consistent electrical characteristics. The limits

do not represent the ultimate performance limits of the device. Use of an optimized RF layout will improves many of the listed

parameters.

Symbol

Parameter

Conditions

Min

-

Typ

92

33

Max Unit

input limiting 3 dB

AM rejection

test at pin IF_AMP_INPUT: per 50 

80 % AM 1 kHz

-

dBm

dB

25

60

-

recovered audio level

15 nF de-emphasis

150 pF de-emphasis

175

530

42

68

260

mV_RMS

dB

-

THD

S/N

total harmonic distortion

signal-to-noise ratio

RSSI output

30

-

no modulation for noise

RF level = 118 dBm

RF level = 68 dBm

RF level = 18 dBm

R₄= 100 k (pin RSSI_OUTPUT)

IF

-

dB

[1]

0

160

800

mV

V

1.7

3.6

-

2.50 3.3

4.80 5.8

V

RSSI range

80

-

dB

RSSI accuracy

-

2.0

1.6

dB

Z_i

input impedance

output impedance

limiter input impedance

output resistance

1.4

k

Z_o

Z

IF

0.85 1.0

k

1.4

-

1.6

58

k

R_o

unmuted audio

muted audio

k

[1] SA614A data sheets refer to power at 50  input termination; about 21 dB less power actually enters the internal 1.5 k input.

SA614A (50 ) - SA614A (1.5 k)/SA615 (1.5 k)

97 dBm - 118 dBm

47 dBm - 68 dBm

+3 dBm - 18 dBm

The SA615 and SA614A are both derived from the same basic die. The SA615 performance plots are directly applicable to the SA614A.

SA614A

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Product data sheet

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SA614A

NXP Semiconductors

Low power FM IF system

12. Performance curves

aaa-009768

200

Φ

(1)

(2)

(3)

(4)

(5)

(6)

150

100

50

0

0.95

0.975

1.0

1.025

1.05

(1) Q =10

(2) Q =20

(3) Q =40

(4) Q =60

(5) Q =80

(6) Q =100

Fig 5. Phase as a function of normalized IF frequency



₁



₁

------

-------

Normalized IF frequency:

= 1 +

SA614A

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Product data sheet

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SA614A

NXP Semiconductors

Low power FM IF system

13. Application information

455 kHz

0.1 μF

ceramic filter

LO input

44.545 MHz

0.1 μF

51 Ω

0.1 μF

455 kHz

ceramic

filter

5.5 μH

+6 V

1 pF

180

pF

680

μH

10 μF

0.1 μF

10 nF

0.1 μF

0.1

μF

SA614A

SA602A

47 pF

150 pF

0.1 μF

0.28

μH

RF input

45 MHz

15 nF

220 pF

1

nF

91

kΩ

0.1 μF

aaa-009761

MUTE

RSSI AUDIO

DATA

+6 V

Fig 6. Typical application cellular radio (45 MHz RF input and 455 kHz IF)

SA614A

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SA614A

NXP Semiconductors

Low power FM IF system

SA614A IF INPUT (μV) (1500 ꢀ)

10

100

1 k

10 k

100 k

AUDIO

0

RSSI

(V)

THD + NOISE

AM (80 % MOD)

NOISE

4

3

2

1

RSSI (VOLTS)

(dB)

-20

THD + NOISE

-40

-60

-80

AM (80 % MOD)

NOISE

-40

-120

-100

-80

-60

-20

SA602A RF INPUT (dBm) (50 ꢀ)

aaa-009988

Fig 7. Performance of the typical cellular radio application

Audio out:

• C message weighted

• 0 dB reference = recovered audio for 8 kHz peak deviation (dB)

13.1 Circuit description

The SA614A is a very high gain, high frequency device. Correct operation is not possible

if good RF layout and gain stage practices are not used. The SA614A cannot be

evaluated independent of circuit, components, and board layout. A physical layout which

correlates to the electrical limits is shown in Figure 17. This configuration can be used as

the basis for production layout.

The SA614A is an IF signal processing system suitable for IF frequencies as high as

21.4 MHz. The device consists of two limiting amplifiers, quadrature detector, direct audio

output, muted audio output, and signal strength indicator (with log output characteristic).

The equivalent circuit is shown in Figure 4.

Figure 7 is the performance of the typical cellular radio application shown in Figure 6 with

45 MHz RF input and 455 kHz IF.

SA614A

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Product data sheet

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SA614A

NXP Semiconductors

Low power FM IF system

13.2 IF amplifiers

The IF amplifier section consists of two log-limiting stages. The first consists of two

differential amplifiers with 39 dB of gain and a small signal bandwidth of 41 MHz (when

driven from a 50  source). The output of the first limiter is a low impedance emitter

follower with 1 k of equivalent series resistance. The second limiting stage consists of

three differential amplifiers with a gain of 62 dB and a small signal AC bandwidth of

28 MHz. The outputs of the final differential stage are buffered to the internal quadrature

detector. One of the outputs is available at pin LIMITER_OUTPUT to drive an external

quadrature capacitor and L/C quadrature tank.

Both of the limiting amplifier stages are DC biased using feedback. The buffered output of

the final differential amplifier is fed back to the input through 42 kresistors. As shown in

Figure 4, the input impedance is established for each stage by tapping one of the

feedback resistors 1.6 k from the input. It requires one additional decoupling capacitor

from the tap point to ground.

9

V+

42 kꢀ

42 kΩ

V+

40 kꢀ

11

12

15

16

700 Ω

8

14

1.6 kΩ

40 kΩ

40 kꢀ

10

7 kΩ

1

80 kꢀ

aaa-009978

aaa-009762

Fig 8. First limiter bias

Fig 9. Second limiter and quadrature detector

BPF

aaa-009763

Fig 10. Feedback paths

SA614A

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Product data sheet

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SA614A

NXP Semiconductors

Low power FM IF system

BPF

high impedance

BPF

high impedance

low impedance

aaa-009764

a. Terminating HIGH impedance filters with transformation to LOW impedance

BPF

A

resistive loss into BPF

aaa-009765

b. LOW impedance termination and gain reduction

Fig 11. Practical termination

430 Ω

16

15

14

13

12

11

10

9

8

430 Ω

SA614A

1

2

3

4

5

6

7

aaa-009766

Fig 12. Crystal input filter with ceramic interstage filter

Because of the very high gain, bandwidth and input impedance of the limiters, there is a

very real potential for instability at IF frequencies above 455 kHz. The basic phenomenon

is shown in Figure 10. Distributed feedback (capacitance, inductance and radiated fields)

forms a divider from the output of the limiters back to the inputs (including RF input). If this

feedback divider does not cause attenuation greater than the gain of the forward path,

then oscillation or low-level regeneration is likely. If regeneration occurs, two symptoms

may be present:

1. The RSSI output is high with no signal input (should nominally be 250 mV or lower)

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SA614A

NXP Semiconductors

Low power FM IF system

2. The demodulated output demonstrates a threshold. Above a certain input level, the

limited signal begins to dominate the regeneration, and the demodulator begins to

operate in a normal manner.

There are three primary ways to deal with regeneration:

1. Minimize the feedback by gain stage isolation.

2. Lower the stage input impedances, thus increasing the feedback attenuation factor.

3. Reduce the gain. Gain reduction can effectively be accomplished by adding

attenuation between stages which can also lower the input impedance. Examples of

impedance/gain adjustment are shown in Figure 11. Reduced gain results in reduced

limiting sensitivity.

A feature of the SA614A IF amplifiers, which is not specified, is low phase shift. The

SA614A is fabricated with a 10 GHz process with very small collector capacitance. It is

advantageous in some applications that the phase shift changes only a few degrees over

a wide range of signal input amplitudes.

13.3 Stability considerations

The high gain and bandwidth of the SA614A in combination with its very low currents

permit circuit implementation with superior performance. However, stability must be

maintained and, to do that, every possible feedback mechanism must be addressed.

These mechanisms are:

1. supply lines and ground

2. stray layout inductances and capacitances,

3. radiated fields, and

4. phase shift

As the system IF increases, so must the attention to fields and strays. However, ground

and supply loops cannot be overlooked, especially at lower frequencies. Even at 455 kHz,

if the supply line is not decoupled, using the test layout in Figure 17, instability occurs. To

decouple, use two high-quality RF capacitors, a 0.1 F monolithic on the VCC pin, and a

6.8 F tantalum on the supply line. An electrolytic is not an adequate substitute. At

10.7 MHz, a 1 F tantalum has proven acceptable with this layout. Every layout must be

evaluated on its own merit, but do not underestimate the importance of good supply

bypass.

At 455 kHz, if the layout of Figure 17 or one substantially similar is used, ceramic filters

can be connected directly to the input and between limiter stages with no special

consideration. At frequencies above 2 MHz, some input impedance reduction is usually

necessary. Figure 11 demonstrates a practical means.

As illustrated in Figure 12, 430  external resistors are applied in parallel to the internal

1.6 k load resistors, thus presenting approximately 330  to the filters. The input filter is

a crystal type for narrowband selectivity. The filter is terminated with a tank which

transforms to 330 W. The interstage filter is a ceramic type which does not contribute to

system selectivity, but does suppress wideband noise and stray signal pickup. In

wideband 10.7 MHz IFs the input filter can also be ceramic, directly connected to pin

IF_AMP_INPUT.

SA614A

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Product data sheet

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SA614A

NXP Semiconductors

Low power FM IF system

In some products, it may be impractical to utilize shielding, but this mechanism may be

appropriate to 10.7 MHz and 21.4 MHz IF. One of the benefits of low current is lower

radiated field strength, but lower does not mean non-existent. A spectrum analyzer with

an active probe clearly shows IF energy with the probe held in the proximity of the second

limiter output or quadrature coil. No specific recommendations are provided, but

mechanical shielding should be considered if layout, bypass, and input impedance

reduction do not solve a stubborn instability.

The final stability consideration is phase shift. The phase shift of the limiters is very low,

but there is phase shift contribution from the quadrature tank and the filters. Most filters

demonstrate a large phase shift across their passband (especially at the edges). If the

quadrature detector is tuned to the edge of the filter passband, the combined filter and

quadrature phase shift can aggravate stability. It is not usually a problem, but should be

kept in mind.

13.4 Quadrature detector

Figure 9 shows an equivalent circuit of the SA614A quadrature detector. It is a multiplier

cell similar to a mixer stage. Instead of mixing two different frequencies, it mixes two

signals of common frequency but different phase. Internal to the device, a constant

amplitude (limited) signal is differentially applied to the lower port of the multiplier. The

same signal is applied single-ended to an external capacitor at pin LIMITER_OUTPUT.

There is a 90° phase shift across the plates of this capacitor. The phase shifted signal

applied to the upper port of the multiplier is at pin QUADRATURE_INPUT. A quadrature tank

(parallel L/C network) permits frequency selective phase shifting at the IF frequency. This

quadrature tank must be returned to ground through a DC blocking capacitor.

The loaded Q of the quadrature tank impacts three fundamental aspects of the detector:

Distortion, maximum modulated peak deviation, and audio output amplitude. Typical

quadrature curves are illustrated in Figure 5. The phase angle translates to a shift in the

multiplier output voltage.

Thus a small deviation gives a large output with a high Q tank. However, as the deviation

from resonance increases, the non-linearity of the curve increases (distortion). With too

much deviation, the signal is outside the quadrature region (limiting the peak deviation

which can be demodulated). If the same peak deviation is applied to a lower Q tank, the

deviation remains in a region of the curve which is more linear (less distortion). However,

it creates a smaller phase angle (smaller output amplitude). Thus the Q of the quadrature

tank must be tailored to the design. Basic equations and an example for determining Q

are shown below. This explanation includes first-order effects only.

SA614A

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Product data sheet

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SA614A

NXP Semiconductors

Low power FM IF system

13.5 Frequency discriminator design equations

V

out

aaa-009767

Fig 13. Frequency discriminator

C_S

1

------------------- ----------------------------------------

V_O

=



₂ V_IN

(1)

C_P+ C_S

₁

-----

S

₁





1 +

+

---------

Q₁S





1

where: ₁=

and Q₁= RC_P+ C_S₁

--------------------------------

LC_P+ C_S

From Equation 1, the phase shift between nodes 1 and 2, or the phase across C_Swill be:

₁

----------

Q₁

 = <V_O– <V_IN= t_g^–1



(2)

-----------------------

2

₁

------







1 –





₁

------











Figure 5 is the plot of  as a function of

. It is notable that at  = ₁, the phase shift

2Q₁



2





--

is and the response is close to a straight line with a slope of

=

.

---------

-------

₁

2Q₁



2

---------

 with respect to the V_IN.

The signal V_Owould have a phase shift of

–

--

₁

If V_IN= A sin(t) =>

2Q₁



2

---------

V_O= Asin t +

–

 

(3)

(4)

(5)

--

₁

Multiplying the two signals in the mixer, and low pass filtering yields:

2Q₁

2



2

---------

V_IN V_O= A sint  sin t +

–

 

--

₁

After low pass filtering =>

2Q₁

---------

₁

2Q₁

---------

₁

1

2

1

2



2

--

V_O

=

A cos

–

 

=

A sin

 

--

2

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SA614A

NXP Semiconductors

Low power FM IF system

₁+ 

--------------------

₁









------

V_O 2Q

= 2Q

(6)

¹

¹₁





2

------

--

For 2Q

<< which is discriminated FM output. Note that  is the deviation

¹₁

frequency from the carrier ₁¹. Example: at 455 kHz IF, with 5 kHz FM deviation. The

maximum normalized frequency is (455  5)/455 kHz = 1.010 or 0.990.

Go to the frequency as a function of normalized frequency curves (Figure 12) and draw a



₁

------

vertical straight line at

= 1.01.

The curves with Q = 100, Q = 40 are not linear, but Q = 20 and less shows better linearity

for this application. Too small Q decreases the amplitude of the discriminated FM signal.

Equation 6 => Choose a Q = 20.

The internal resistance of the SA614A is 40 k From Q₁= RC_P+ C_S₁, and then

1

₁=

, it results that C + C = 174 pF and L = 0.7 mH.

P S

--------------------------------

LC_P+ C_S

A more exact analysis including the source resistance of the previous stage shows a

series and a parallel resonance in the phase detector tank. To make the parallel and

series resonances close, and to get maximum attenuation of higher harmonics at

455 kHz IF, a C_S= 10 pF and C_P= 164 pF provided the best results. For commercial

purposes, values of 150 pF or 180 pF may be practical. A variable inductor which can be

adjusted around 0.7 mH should be chosen and optimized for minimum distortion. (For

10.7 MHz, a value of C_S= 1 pF is recommended.)

13.6 Audio outputs

Two audio outputs are provided. Both are PNP current-to-voltage converters with 55 k

nominal internal loads. The unmuted output is always active to permit the use of signaling

tones in systems such as cellular radio. The other output can be muted with 70 dB typical

attenuation. The two outputs have an internal 180° phase difference.

The nominal frequency response of the audio outputs is 300 kHz. This response can be

increased with the addition of external resistors between the output pins and ground. The

resistors are placed in parallel with the internal 55 k resistors and they lower the output

time constant. The output structure is a current-to-voltage converter where current is

driven into the resistance, creating a voltage drop. By adding external parallel resistance,

it also lowers the output audio amplitude and DC level.

This technique of audio bandwidth expansion can be effective in many applications such

as SCA receivers and data transceivers. Because the two outputs have a 180° phase

relationship, FSK demodulation can be accomplished by applying the two output

differentially across the inputs of an op amp or comparator. Once the threshold of the

reference frequency (or no-signal condition) has been established, the two outputs shift in

opposite directions (higher or lower output voltage) as the input frequency shifts. The

1. Ref. Krauss, Raab, Bastian: Solid-State radio Eng.; Wiley, 1980, p.311.

SA614A

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Product data sheet

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SA614A

NXP Semiconductors

Low power FM IF system

output of the comparator is logic output. The choice of op amp or comparator depends on

the data rate. With high IF frequency (10 MHz and above), and wide IF bandwidth (L/C

filters) data rates in excess of 4 Mbaud are possible.

13.7 RSSI

The Received Signal Strength Indicator (RSSI), of the SA614A demonstrates monotonic

logarithmic output over a range of 90 dB. The signal strength output is derived from the

summed stage currents in the limiting amplifiers. It is independent of the IF frequency.

Thus, unfiltered signals at the limiter inputs, spurious products, or regenerated signals

manifest themselves as RSSI outputs. An RSSI output of greater than 250 mV with no

signal (or a very small signal) applied, is an indication of possible regeneration or

oscillation.

In order to achieve optimum RSSI linearity, there must be a 12 dB insertion loss between

the first and second limiting amplifiers. With a typical 455 kHz ceramic filter, there is a

nominal 4 dB insertion loss in the filter. An additional 6 dB is lost in the interface between

the filter and the input of the second limiter. A small amount of additional loss must be

introduced with a typical ceramic filter. In the test circuit used for cellular radio applications

(Figure 5), the optimum linearity was achieved with a 5.1 k resistor. The resistor was

placed between the output of the first limiter (pin IF_AMP_OUTPUT) and the input of the

interstage filter. With this resistor from pin IF_AMP_OUTPUT to the filter, sensitivity of

0.25 V for 12 dB SINAD was achieved. With the 3.6 k resistor, sensitivity was

optimized at 0.22 V for 12 dB SINAD with minor change in the RSSI linearity.

Any application requiring optimized RSSI linearity, such as spectrum analyzers, cellular

radio, and certain types of telemetry, requires careful attention to limiter interstage

component selection. This is especially true with high IF frequencies which require

insertion loss or impedance reduction for stability.

At low frequencies, the RSSI makes an excellent logarithmic AC voltmeter.

For data applications, the RSSI is effective as an Amplitude Shift Keyed (ASK) data slicer.

If a comparator is applied to the RSSI and the threshold set slightly above the no signal

level, when an in-band signal is received the comparator is sliced. Unlike FSK

demodulation, the maximum data rate is limited. An internal capacitor limits the RSSI

frequency response to approximately 100 kHz. At high data rates, the rise and fall times

are not symmetrical.

The RSSI output is a current-to-voltage converter similar to the audio outputs. However,

an external resistor is required. With a 91 k resistor, the output characteristic is 0.5 V for

a 10 dB change in the input amplitude.

13.8 Additional circuitry

Internal to the SA614A are voltage and current regulators which have been temperature

compensated to maintain the performance of the device over a wide temperature range.

These regulators are not accessible to the user.

SA614A

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Product data sheet

Rev. 4 — 14 February 2014

17 of 28

SA614A

NXP Semiconductors

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14. Test information

F

1

C

4

Q = 20 loaded

C

input

1

R

2

C

2

C

6

R

5

3

F

2

R

1

C

7

C

3

SA614A

C

8

S

1

R

4

C

9

C

10

C

12

C

11

DATA

AUDIO

output

RSSI

output

MUTE

input

aaa-009812

Fig 14. SA614A test circuit

Table 7.

SA616DK demo board component list

Component Value

Description

C1

C2

C3

C4

C5

C6

C7

C8

C9

C10

C11

C12

F1

100 nF, +80 %, 20 %,63 V

K10000-25V ceramic

100 nF, +10 %, 50 V

100 nF, 10 %, 50 V

100 nF, +10 %, 50 V

100 nF, 10 %, 50 V

10 pF, 2 %, 100 V

100 nF, 10 %, 50 V

15 nF, 10 %, 50 V

150 pF 2 %, 100 V

1 nF, 10 %, 100 V

6.8 F 20 %, 25 V

455 kHz

-

NPO ceramic

-

N1500 ceramic

K2000-Y5P ceramic

tantalum

ceramic filter Murata SFG455A3

Toko RMC 2A6597H

metal film

F2

455 kHz, Ce = 180 pF

51 , 1 %, 1/4 W

1500 , 1 %, 1/4 W

1500 , 5 %, 1/8 W

100 k, 1 %, 1/4 W

R1

R2

R3

R4

metal film

carbon composition

metal film

SA614A

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Product data sheet

Rev. 4 — 14 February 2014

18 of 28

SA614A

NXP Semiconductors

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SIGNETICS

NE614 TEST CKT

MUTE

aaa-009813

aaa-009814

Fig 15. Components layout (viewed from the top)

Fig 16. Bottom layout (viewed from the top)

SIGNETICS

NE614 TEST CKT

MUTE

aaa-009813

Fig 17. Print layout (viewed from the top)

SA614A

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Product data sheet

Rev. 4 — 14 February 2014

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SA614A

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15. Package outline

SO16: plastic small outline package; 16 leads; body width 3.9 mm

SOT109-1

D

E

A

X

c

y

H

v

M

A

E

Z

16

9

Q

A

2

A

(A )

3

A

1

pin 1 index

θ

L

p

L

1

8

e

w

M

detail X

b

p

0

2.5

scale

5 mm

DIMENSIONS (inch dimensions are derived from the original mm dimensions)

A

(1)

UNIT

A

b

c

D

E

e

H

L

p

Q

v

w

y

Z

θ

1

2

3

p

E

max.

0.25

0.10

1.45

1.25

0.49

0.36

0.25

0.19

10.0

9.8

4.0

3.8

6.2

5.8

1.0

0.4

0.7

0.6

0.7

0.3

mm

1.27

0.05

1.05

0.041

1.75

0.25

0.01

0.25

0.01

0.25

0.1

8^o

0^o

0.010 0.057

0.004 0.049

0.019 0.0100 0.39

0.014 0.0075 0.38

0.16

0.15

0.244

0.228

0.039 0.028

0.016 0.020

0.028

0.012

inches

0.069

0.01 0.004

Note

1. Plastic or metal protrusions of 0.15 mm (0.006 inch) maximum per side are not included.

REFERENCES

OUTLINE

EUROPEAN

PROJECTION

ISSUE DATE

VERSION

IEC

JEDEC

JEITA

99-12-27

03-02-19

SOT109-1

076E07

MS-012

Fig 18. Package outline SOT109-1 (SO16)

SA614A

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Product data sheet

Rev. 4 — 14 February 2014

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SA614A

NXP Semiconductors

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HXQFN16: plastic thermal enhanced extremely thin quad flat package; no leads;

16 terminals; body 3 x 3 x 0.5 mm

SOT1039-2

D

B

A

terminal 1

index area

E

A

1

c

detail X

e

1

1/2 e

b

C

y

e

v

w

C A

B

C

y

C

1

5

8

L

4

1

9

e

E

e

2

h

1/2 e

12

X

terminal 1

index area

16

13

D

h

0

1

scale

2 mm

v

Dimensions

Unit

A

1

b

c

D

h

E

h

e

L

0.40

w

y

1

2

max 0.5 0.05 0.35

3.1 1.95 3.1 1.95

mm nom

min

0.30 0.127 3.0 1.85 3.0 1.85 0.5 1.5 1.5 0.35 0.1 0.05 0.05 0.1

0.00 0.25 2.9 1.75 2.9 1.75 0.30

sot1039-2_po

References

Outline

version

European

projection

Issue date

IEC

- - -

JEDEC

JEITA

- - -

10-07-29

11-03-30

SOT1039-2

Fig 19. Package outline SOT1039-2 (HXQFN16)

SA614A

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Product data sheet

Rev. 4 — 14 February 2014

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SA614A

NXP Semiconductors

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16. Soldering of SMD packages

This text provides a very brief insight into a complex technology. A more in-depth account

of soldering ICs can be found in Application Note AN10365 “Surface mount reflow

soldering description”.

16.1 Introduction to soldering

Soldering is one of the most common methods through which packages are attached to

Printed Circuit Boards (PCBs), to form electrical circuits. The soldered joint provides both

the mechanical and the electrical connection. There is no single soldering method that is

ideal for all IC packages. Wave soldering is often preferred when through-hole and

Surface Mount Devices (SMDs) are mixed on one printed wiring board; however, it is not

suitable for fine pitch SMDs. Reflow soldering is ideal for the small pitches and high

densities that come with increased miniaturization.

16.2 Wave and reflow soldering

Wave soldering is a joining technology in which the joints are made by solder coming from

a standing wave of liquid solder. The wave soldering process is suitable for the following:

• Through-hole components

• Leaded or leadless SMDs, which are glued to the surface of the printed circuit board

Not all SMDs can be wave soldered. Packages with solder balls, and some leadless

packages which have solder lands underneath the body, cannot be wave soldered. Also,

leaded SMDs with leads having a pitch smaller than ~0.6 mm cannot be wave soldered,

due to an increased probability of bridging.

The reflow soldering process involves applying solder paste to a board, followed by

component placement and exposure to a temperature profile. Leaded packages,

packages with solder balls, and leadless packages are all reflow solderable.

Key characteristics in both wave and reflow soldering are:

• Board specifications, including the board finish, solder masks and vias

• Package footprints, including solder thieves and orientation

• The moisture sensitivity level of the packages

• Package placement

• Inspection and repair

• Lead-free soldering versus SnPb soldering

16.3 Wave soldering

Key characteristics in wave soldering are:

• Process issues, such as application of adhesive and flux, clinching of leads, board

transport, the solder wave parameters, and the time during which components are

exposed to the wave

• Solder bath specifications, including temperature and impurities

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Product data sheet

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SA614A

NXP Semiconductors

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16.4 Reflow soldering

Key characteristics in reflow soldering are:

• Lead-free versus SnPb soldering; note that a lead-free reflow process usually leads to

higher minimum peak temperatures (see Figure 20) than a SnPb process, thus

reducing the process window

• Solder paste printing issues including smearing, release, and adjusting the process

window for a mix of large and small components on one board

• Reflow temperature profile; this profile includes preheat, reflow (in which the board is

heated to the peak temperature) and cooling down. It is imperative that the peak

temperature is high enough for the solder to make reliable solder joints (a solder paste

characteristic). In addition, the peak temperature must be low enough that the

packages and/or boards are not damaged. The peak temperature of the package

depends on package thickness and volume and is classified in accordance with

Table 8 and 9

Table 8.

SnPb eutectic process (from J-STD-020D)

Package thickness (mm) Package reflow temperature (C)

Volume (mm³)

< 350

 350

220

< 2.5

235

220

 2.5

220

Table 9.

Lead-free process (from J-STD-020D)

Package thickness (mm) Package reflow temperature (C)

Volume (mm³)

< 350

260

350 to 2000

> 2000

260

< 1.6

260

250

245

1.6 to 2.5

> 2.5

260

245

250

245

Moisture sensitivity precautions, as indicated on the packing, must be respected at all

times.

Studies have shown that small packages reach higher temperatures during reflow

soldering, see Figure 20.

SA614A

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Product data sheet

Rev. 4 — 14 February 2014

23 of 28

SA614A

NXP Semiconductors

Low power FM IF system

maximum peak temperature

= MSL limit, damage level

temperature

minimum peak temperature

= minimum soldering temperature

peak

temperature

time

001aac844

MSL: Moisture Sensitivity Level

Fig 20. Temperature profiles for large and small components

For further information on temperature profiles, refer to Application Note AN10365

“Surface mount reflow soldering description”.

17. Abbreviations

Table 10. Abbreviations

Acronym

AM

Description

Amplitude Modulation

ASK

FM

Amplitude Shift Keying

Frequency Modulation

FSK

IF

Frequency Shift Keying

Intermediate Frequency

Printed-Circuit Board

PCB

RF

Radio Frequency

RSSI

SINAD

Received Signal Strength Indicator

Signal-to-Noise And Distortion ratio

SA614A

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Product data sheet

Rev. 4 — 14 February 2014

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SA614A

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18. Revision history

Table 11. Revision history

Document ID

SA614A v.4

Release date

Data sheet status

Change notice

Supersedes

20140214

Product data sheet

-

SA614A v.3

Modifications:

• The format of this document has been redesigned to comply with the new identity guidelines of

NXP Semiconductors.

• Legal texts have been adapted to the new company name where appropriate.

• Added type number SA614AHR.

SA614A v.3

SA614A v.2

SA614A v.1

19971107

19941215

Product specification

-

SA614A v.2

SA614A v.1

-

SA614A

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Product data sheet

Rev. 4 — 14 February 2014

25 of 28

SA614A

NXP Semiconductors

Low power FM IF system

19. Legal information

19.1 Data sheet status

Document status^[1][2]

Product status^[3]

Development

Definition

Objective [short] data sheet

This document contains data from the objective specification for product development.

This document contains data from the preliminary specification.

This document contains the product specification.

Preliminary [short] data sheet Qualification

Product [short] data sheet Production

[1]

[2]

[3]

Please consult the most recently issued document before initiating or completing a design.

The term ‘short data sheet’ is explained in section “Definitions”.

The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices. The latest product status

information is available on the Internet at URL http://www.nxp.com.

Suitability for use — NXP Semiconductors products are not designed,

19.2 Definitions

authorized or warranted to be suitable for use in life support, life-critical or

safety-critical systems or equipment, nor in applications where failure or

malfunction of an NXP Semiconductors product can reasonably be expected

to result in personal injury, death or severe property or environmental

damage. NXP Semiconductors and its suppliers accept no liability for

inclusion and/or use of NXP Semiconductors products in such equipment or

applications and therefore such inclusion and/or use is at the customer’s own

risk.

Draft — The document is a draft version only. The content is still under

internal review and subject to formal approval, which may result in

modifications or additions. NXP Semiconductors does not give any

representations or warranties as to the accuracy or completeness of

information included herein and shall have no liability for the consequences of

use of such information.

Short data sheet — A short data sheet is an extract from a full data sheet

with the same product type number(s) and title. A short data sheet is intended

for quick reference only and should not be relied upon to contain detailed and

full information. For detailed and full information see the relevant full data

sheet, which is available on request via the local NXP Semiconductors sales

office. In case of any inconsistency or conflict with the short data sheet, the

full data sheet shall prevail.

Applications — Applications that are described herein for any of these

products are for illustrative purposes only. NXP Semiconductors makes no

representation or warranty that such applications will be suitable for the

specified use without further testing or modification.

Customers are responsible for the design and operation of their applications

and products using NXP Semiconductors products, and NXP Semiconductors

accepts no liability for any assistance with applications or customer product

design. It is customer’s sole responsibility to determine whether the NXP

Semiconductors product is suitable and fit for the customer’s applications and

products planned, as well as for the planned application and use of

customer’s third party customer(s). Customers should provide appropriate

design and operating safeguards to minimize the risks associated with their

applications and products.

Product specification — The information and data provided in a Product

data sheet shall define the specification of the product as agreed between

NXP Semiconductors and its customer, unless NXP Semiconductors and

customer have explicitly agreed otherwise in writing. In no event however,

shall an agreement be valid in which the NXP Semiconductors product is

deemed to offer functions and qualities beyond those described in the

Product data sheet.

NXP Semiconductors does not accept any liability related to any default,

damage, costs or problem which is based on any weakness or default in the

customer’s applications or products, or the application or use by customer’s

third party customer(s). Customer is responsible for doing all necessary

testing for the customer’s applications and products using NXP

Semiconductors products in order to avoid a default of the applications and

the products or of the application or use by customer’s third party

customer(s). NXP does not accept any liability in this respect.

19.3 Disclaimers

Limited warranty and liability — Information in this document is believed to

be accurate and reliable. However, NXP Semiconductors does not give any

representations or warranties, expressed or implied, as to the accuracy or

completeness of such information and shall have no liability for the

consequences of use of such information. NXP Semiconductors takes no

responsibility for the content in this document if provided by an information

source outside of NXP Semiconductors.

Limiting values — Stress above one or more limiting values (as defined in

the Absolute Maximum Ratings System of IEC 60134) will cause permanent

damage to the device. Limiting values are stress ratings only and (proper)

operation of the device at these or any other conditions above those given in

the Recommended operating conditions section (if present) or the

Characteristics sections of this document is not warranted. Constant or

repeated exposure to limiting values will permanently and irreversibly affect

the quality and reliability of the device.

In no event shall NXP Semiconductors be liable for any indirect, incidental,

punitive, special or consequential damages (including - without limitation - lost

profits, lost savings, business interruption, costs related to the removal or

replacement of any products or rework charges) whether or not such

damages are based on tort (including negligence), warranty, breach of

contract or any other legal theory.

Terms and conditions of commercial sale — NXP Semiconductors

products are sold subject to the general terms and conditions of commercial

sale, as published at http://www.nxp.com/profile/terms, unless otherwise

agreed in a valid written individual agreement. In case an individual

agreement is concluded only the terms and conditions of the respective

agreement shall apply. NXP Semiconductors hereby expressly objects to

applying the customer’s general terms and conditions with regard to the

purchase of NXP Semiconductors products by customer.

Notwithstanding any damages that customer might incur for any reason

whatsoever, NXP Semiconductors’ aggregate and cumulative liability towards

customer for the products described herein shall be limited in accordance

with the Terms and conditions of commercial sale of NXP Semiconductors.

Right to make changes — NXP Semiconductors reserves the right to make

changes to information published in this document, including without

limitation specifications and product descriptions, at any time and without

notice. This document supersedes and replaces all information supplied prior

to the publication hereof.

No offer to sell or license — Nothing in this document may be interpreted or

construed as an offer to sell products that is open for acceptance or the grant,

conveyance or implication of any license under any copyrights, patents or

other industrial or intellectual property rights.

SA614A

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Product data sheet

Rev. 4 — 14 February 2014

26 of 28

SA614A

NXP Semiconductors

Low power FM IF system

Export control — This document as well as the item(s) described herein

may be subject to export control regulations. Export might require a prior

authorization from competent authorities.

NXP Semiconductors’ specifications such use shall be solely at customer’s

own risk, and (c) customer fully indemnifies NXP Semiconductors for any

liability, damages or failed product claims resulting from customer design and

use of the product for automotive applications beyond NXP Semiconductors’

standard warranty and NXP Semiconductors’ product specifications.

Non-automotive qualified products — Unless this data sheet expressly

states that this specific NXP Semiconductors product is automotive qualified,

the product is not suitable for automotive use. It is neither qualified nor tested

in accordance with automotive testing or application requirements. NXP

Semiconductors accepts no liability for inclusion and/or use of

Translations — A non-English (translated) version of a document is for

reference only. The English version shall prevail in case of any discrepancy

between the translated and English versions.

non-automotive qualified products in automotive equipment or applications.

In the event that customer uses the product for design-in and use in

automotive applications to automotive specifications and standards, customer

(a) shall use the product without NXP Semiconductors’ warranty of the

product for such automotive applications, use and specifications, and (b)

whenever customer uses the product for automotive applications beyond

19.4 Trademarks

Notice: All referenced brands, product names, service names and trademarks

are the property of their respective owners.

20. Contact information

For more information, please visit: http://www.nxp.com

For sales office addresses, please send an email to: salesaddresses@nxp.com

SA614A

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Product data sheet

Rev. 4 — 14 February 2014

27 of 28

SA614A

NXP Semiconductors

Low power FM IF system

21. Contents

1

2

3

4

5

General description. . . . . . . . . . . . . . . . . . . . . . 1

Features and benefits . . . . . . . . . . . . . . . . . . . . 1

Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Ordering information. . . . . . . . . . . . . . . . . . . . . 1

Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 2

6

6.1

6.2

Pinning information. . . . . . . . . . . . . . . . . . . . . . 3

Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 4

7

Functional description . . . . . . . . . . . . . . . . . . . 5

Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . . 6

Thermal characteristics . . . . . . . . . . . . . . . . . . 6

Static characteristics. . . . . . . . . . . . . . . . . . . . . 6

Dynamic characteristics . . . . . . . . . . . . . . . . . . 7

Performance curves . . . . . . . . . . . . . . . . . . . . . 8

8

9

10

11

12

13

Application information. . . . . . . . . . . . . . . . . . . 9

Circuit description. . . . . . . . . . . . . . . . . . . . . . 10

IF amplifiers . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Stability considerations . . . . . . . . . . . . . . . . . 13

Quadrature detector . . . . . . . . . . . . . . . . . . . . 14

Frequency discriminator design equations. . . 15

Audio outputs . . . . . . . . . . . . . . . . . . . . . . . . . 16

RSSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Additional circuitry . . . . . . . . . . . . . . . . . . . . . 17

13.1

13.2

13.3

13.4

13.5

13.6

13.7

13.8

14

15

Test information. . . . . . . . . . . . . . . . . . . . . . . . 18

Package outline . . . . . . . . . . . . . . . . . . . . . . . . 20

16

Soldering of SMD packages . . . . . . . . . . . . . . 22

Introduction to soldering . . . . . . . . . . . . . . . . . 22

Wave and reflow soldering . . . . . . . . . . . . . . . 22

Wave soldering. . . . . . . . . . . . . . . . . . . . . . . . 22

Reflow soldering. . . . . . . . . . . . . . . . . . . . . . . 23

16.1

16.2

16.3

16.4

17

18

Abbreviations. . . . . . . . . . . . . . . . . . . . . . . . . . 24

Revision history. . . . . . . . . . . . . . . . . . . . . . . . 25

19

Legal information. . . . . . . . . . . . . . . . . . . . . . . 26

Data sheet status . . . . . . . . . . . . . . . . . . . . . . 26

Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Disclaimers. . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Trademarks. . . . . . . . . . . . . . . . . . . . . . . . . . . 27

19.1

19.2

19.3

19.4

20

21

Contact information. . . . . . . . . . . . . . . . . . . . . 27

Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Please be aware that important notices concerning this document and the product(s)

described herein, have been included in section ‘Legal information’.

For more information, please visit: http://www.nxp.com

For sales office addresses, please send an email to: salesaddresses@nxp.com

Date of release: 14 February 2014

Document identifier: SA614A


型号：	SA614AHRX
厂家：	NXP
描述：	SA614A - Low power FM IF system QFN 16-Pin 商用集成电路
文件：	总28页 (文件大小：1376K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

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