MITEL SL25241C, SL2524B, SL2524C, SL2524HP, SL2524LC Datasheet

1.3GHz Dual Wideband Logarithmic Amplifier

The SL2524 is a pin compatible replacement for the
SL2521 and SL2522 series of log amplifiers, and exhibits a
superior stability performance. The amplifier is a successive
detection type which provides linear gain and accurate loga­rithmic signal compression over a wide bandwidth. The two
stages can be operated independently.

When six stages (three SL2524s) are cascaded the strip
can be used for IFs between 30-650MHz whilst achieving
greater than 65dB dynamic range with a log accuracy of
<±1.0dB. The balanced limited output also offers accurate
phase information with input amplitude.

FEATURES

■ 1.3GHz Bandwidth (-3dB)

■ Balanced IF limiting

■ 3ns Rise Times/5ns Fall Times (six stages)

■ 20ns Pulse Handling (six stages)

■ Temperature Stabilised

■ Surface Mountable

SL2524

DS4548 - 2.1 July 1995

APPLICATIONS

■ Ultra Wideband Log Receivers

■ Channelised Receivers

■ Monopulse Applications

ABSOLUTE MAXIMUM RATINGS

Supply Voltage (VCC above VEE) +7.0V
Storage temperature -65°C to +150°C
Operating temperature range
SL2524/B/LC -40°C to +85°C
SL2524/C/HP -30°C to +85°C
Junction temperature - LC20 +175°C

- HP20 +150°C

Applied DC voltage to RF input ±0.4V (between RF I/P
Applied RF power to RF input +15dBm

Value of R
Thermal resistance:-

resistors NOT less than 180Ω

SET

Die to case -LC 20 28°C/W

- HP20 20°C/W

Die to ambient - LC20 73°C/W

- HP20 82°C/W

ORDERING INFORMATION

SL2524/B/LC (Ceramic leadless chip carrier package)
SL2524/C/HP (Plastic J lead chip carrier package)
SL2524/NA/1C (DC probe tested bare die)
5962 - 92315 (SMD)

pins)

OPTIONAL PIN

REFERENCE

PIN DESCRIPTION

1 SUB V
2 IF OUTPUT (A)

EE

3 IF OUTPUT (A)
4VEE (A)
5 OUTPUT VC (A)
6 IF INPUT (A)
7 IF INPUT (A)
8VCC (A)
9 DET. OUTPUT (A)
10 R SET (A)

Fig.1 Pin connections top view

PIN DESCRIPTION

11 N/C
12 R SET (B)
13 DET. OUTPUT (B)
14 V
15 IF OUTPUT (B)

(B)

CC

16 IF OUTPUT (B)
17 OUTPUT VCC (B)
18 VEE (B)
19 IF INPUT (B)
20 IF INPUT (B)

SL2524

Fig.2 Circuit diagram of single stage A - (stage B pin Nos bracketed)

Fig.3 Pad map for SL2524 naked die

2

ELECTRICAL CHARACTERISTICS - SL2524B

Guaranteed at the following test conditions unless otherwise stated

Frequency = 200MHz, T

Load impedance = 50Ω, Test Circuit = Fig. 4, R

amb = +25°C, Input power = -30dBm, VCC = 6V ±0.1V, Source Impedance = 50Ω.

= 300Ω. Tested as a dual stage.

SET

SL2524

Characteristic

Supply current
Small signal gain (dual stage,

single ended)

Detected output current (max)

Detected output current
(no signal)

Min

70

9.6

10.1

9.9

9.5

9.7

9.3

8.2

3.20

3.05

3.15

3.10

2.80

2.90

2.85

0.85

0.80

0.80

Value

Typ

87

11.4

11.6

11.3

11.0

11.2

10.7

9.7

3.45

3.25

3.30

3.30

3.10

3.15

3.10

0.95

0.93

0.90

Max

100

13.0

13.1

12.7

12.5

12.7

12.1

11.2

3.70

3.45

3.45

3.50

3.30

3.45

3.65

1.15

1.10

1.10

Units

mA

dB
dB

dB
dB

dB
dB

dB
mA
mA
mA

mA

mA
mA

mA

mA
mA
mA

Conditions

T

amb = +25°C f = 25MHz See Notes 1, 3

Tamb = -40°C f = 200MHz See Notes 2, 3
T

amb = +25°C f = 200MHz See Note 3

T

amb = +85°C f = 200MHz See Notes 2, 3
amb = -40°C f = 500MHz See Notes 2, 3

T

amb = +25°C f = 500MHz See Note 3

T
T

amb = +85°C f = 500MHz See Notes 2, 3
amb = +25°C, V

T
See Note 1
T

amb = -40°C, V

See Note 2

= 0dBm, f = 25MHz

IN

= 0dBm, f = 200MHz

IN

Tamb = +25°C, VIN = 0dBm, f = 200MHz
T

amb = +85°C, V

See Note 2

= 0dBm, f = 200MHz

IN

Tamb = -40°C, VIN = 0dBm, f = 500MHz
See Note 2
Tamb = +25°C, VIN = 0dBm, f = 500MHz
T

amb = +85°C, V

See Note 2

= 0dBm, f = 500MHz

IN

Tamb = -40°C, See Note 2
T

amb = +25°C, See Note 2
amb = +85°C, See Note 2

T

Upper cut off frequency (RF)

Lower cut off frequency (RF)
Detector cut off frequency
Limited IF O/P voltage
Phase variation with input level

600
900
600

135

1100
1100

800

0.35
700
155

0±2.0

1

175

0±3.0

MHz
MHz
MHz

MHz
MHz

mV

Degree

(normalised to -30dBm)

-4.0±2.0

Limited O/P var with temp.
Noise figure
Max I/P before overload
Input impedance
Output impedance

NOTES

1. Parameter guaranteed but not tested

2. Tested at 25°C only, but guaranteed at temperature

3. Gain will typically increase by 6dB, when RF outputs use 1kΩ loads in place of 50Ω

±12

14
15

1

50

-4.0±3.0

±25

Degree

mV

dB

dBm

kΩ

Ω

-3dB w.r.t 200MHz, T

amb = -40°C

See Note 2

-3dB w.r.t 200MHz, T

amb = +25°C

-3dB w.r.t 200MHz, Tamb = +85°C
See Note 2

-3dB w.r.t 200MHz, Tamb = +25°C
50% O/P current w.r.t. 200MHz
I/P power = 0dBm, T

amb = +25°C

Frequency = 70MHz, -55 to +3dBm
See Note 2
Frequency = 200MHz, -55 to +3dBm
See Note 2

See Note 1

1kΩ in parallel with 2pF

3

SL2524

ELECTRICAL CHARACTERISTICS - SL2524C

Guaranteed at the following test conditions unless otherwise stated

Frequency = 200MHz, T
Load impedance = 50Ω, Test Circuit = Fig. 4, R

amb = +25°C, Input power = -30dBm, VCC = 6V ±0.1V, Source Impedance = 50Ω.

= 300Ω. Tested as a dual stage.

SET

Characteristic

Supply current
Small signal gain (dual stage,

single ended)

Detected output current (max)

Detected output current
(no signal)

Min

70

9.6

9.6

9.4

9.0

9.2

8.8

7.7

3.20

2.95

3.05

3.00

2.70

2.80

2.75

0.75

0.70

0.70

Value

Typ

87

11.4

11.6

11.3

11.0

11.2

10.7

9.7

3.45

3.25

3.30

3.30

3.10

3.15

3.10

0.95

0.93

0.90

Max

100

13.0

13.6

13.2

13.0

13.2

12.6

11.7

3.70

3.55

3.55

3.50

3.30

3.55

3.75

1.25

1.20

1.20

Units

mA

dB
dB

dB
dB

dB
dB
dB

mA
mA

mA
mA

mA
mA
mA

mA
mA
mA

Conditions

T

amb = +25°C f = 25MHz See Note 3
amb = -30°C f = 200MHz See Notes 2, 3

T

amb = +25°C f = 200MHz See Note 3

T
T

amb = +85°C f = 200MHz See Notes 2, 3
amb = -30°C f = 500MHz See Notes 1, 3

T
T

amb = +25°C f = 500MHz See Note 1

T

amb = +85°C f = 500MHz See Notes 1, 3

Tamb = +25°C, VIN = 0dBm, f = 25MHz
T

amb = -30°C, V

See Note 2
T

amb = +25°C, V

T

amb = +85°C, V

See Note 2

= 0dBm, f = 200MHz

IN

= 0dBm, f = 200MHz

IN

= 0dBm, f = 200MHz

IN

Tamb = -30°C, VIN = 0dBm, f = 500MHz
See Note 1
T

amb = +25°C, V

See Note 1
T

amb = +85°C, V

See Note 1

amb = -30°C, See Note 2

T
T

amb = +25°C, See Note 2

T

amb = +85°C, See Note 2

= 0dBm, f = 500MHz

IN

= 0dBm, f = 500MHz

IN

Upper cut off frequency (RF)

Lower cut off frequency (RF)
Detector cut off frequency
Limited IF O/P voltage
Phase variation with input level

105

1000

0.35
600
135

0±2.0

2

175

MHz

MHz
MHz

mV

Degree

(normalised to -30dBm)

-4.0±2.0

Limited O/P var with temp.
Noise figure
Max I/P before overload
Input impedance
Output impedance

NOTES

1. Parameter guaranteed but not tested

2. Tested at 25°C only, but guaranteed at temperature

3. Gain will typically increase by 6dB, when RF outputs use 1kΩ loads in place of 50Ω

±12

14
15

1

50

±25

Degree

mV

dB

dBm

kΩ

Ω

-3dB w.r.t 200MHz, T

amb = +25°C

See Note 1

-3dB w.r.t 200MHz, T

amb = +25°C

50% O/P current w.r.t. 200MHz
I/P power = 0dBm, T

amb = +25°C

Frequency = 70MHz, -55 to +3dBm
See Note 1
Frequency = 200MHz, -55 to +3dBm
See Note 1

See Note 1

1kΩ in parallel with 2pF

4

GENERAL DESCRIPTION

The SL2524 is primarily intended for use in Radar and EW
receivers. Six stages (3 chip carriers) can be cascaded to form
a very wideband logarithmic ampifier offering >65dB of input
dynamic range, with pulse handling of better than 25ns. (See
figs 5 and 6.)

A six stange strip also offers balanced IF limiting, linearity
(log accuracy) of < ±1.0dB, temperature stabilisation and
programmable detector characteristics.

The detector has an external resistor set (R
allows the major characteristics of the detector to be
programmed. With six stage strip it is possible to vary the
value of R
error/linearity.

on each detector and so improve the overall log

SET

) pin which

SET

SL2524

The detector is full wave and good slew rates are achieved
with 2ns rise and 5ns fall times (no video filter). The video
bandwidth of a six stage strip is typically 600MHz (-3dB).

The amplifier also offers balanced IF limiting, low phase
shift versus input amplitude, and at an IF of 120MHz, less than
5° of phase change is achievable over the input level of

-55dBm to +5dBm.

The IF and Video ports can be used simultaneously, so
offering phase, frequency and pulse (video) information. A
slight loss of dynamic range (2dB) will be observed when the
IF ports are used in conjunction with the video.

Fig.4 Test circuit

Fig.5 Schematic diagram showing configuration of SD Log strip

5

SL2524

Fig.6 Circuit diagram for 6-log strip (results shown in figs. 11 to 24 were achieved with this circuit)

Typical characteristics for a dual - stage amplifier (i.e. One SL2524)

Fig.7 IF Gain vs frequency of 2 amplifiers (One SL2524)

6