ADL5519ACPZ-R2 AD [Analog Devices], ADL5519ACPZ-R2 Datasheet - Page 14

• Manufacturer Part Number: ADL5519ACPZ-R2
• Description: 1 MHz to 10 GHz, 50 dB Dual Log Detector/Controller
• Manufacturer: AD [Analog Devices]

ADL5519
USING THE ADL5519
BASIC CONNECTIONS
The ADL5519 is specified for operation up to 10 GHz; as a
result, low impedance supply pins with adequate isolation
between functions are essential. A power supply voltage of
between 3.0 V and 5.5 V should be applied to VPSA, VPSB,
and VPSR. Power supply decoupling capacitors of 100 pF
and 0.1 μF should be connected close to these power
supply pins.
INHB
The paddle of the LFCSP_VD package is internally
connected to COMR. For optimum thermal and electrical
performance, the paddle should be soldered to a low
impedance ground plane.
INPUT SIGNAL COUPLING
The RF inputs (INHA and INHB) are single-ended and
must be ac-coupled. INLA and INLB (input common)
should be ac-coupled to ground. Suggested coupling
capacitors are 47 nF ceramic 0402-style capacitors for input
frequencies of 1 MHz to 10 GHz. The coupling capacitors
should be mounted close to the INHA[INHB] and
INLA[INLB} pins. The coupling capacitor values can be
increased to lower the input stage’s high-pass cutoff
frequency. The high-pass corner is set by the input coupling
capacitors and the internal 10 pF high-pass capacitor. The
dc voltage on INHA[INHB] and INLA[INLB] is about one
diode voltage drop below the supply voltage.
INHA
52.3Ω
52.3Ω
R5
R6
47nF
47nF
47nF
47nF
C2
VPSA
C1
C3
C4
0.1μF
C12
25
26
27
28
29
30
31
32
INHA
INLA
COMR
PWDN
COMR
COMR
INLB
INHB
COMR
COMR COMR
100pF
24
1
R3
0Ω
C7
Figure 11. Basic Connections
C11
100pF
C16
0.1μF
COMR
23
2
VPSB
VPSB
VPSA
22
3
R11
ADL5519ACPZ
0Ω
EXPOSED PADDLE
ADJA
ADJB
21
4
TEXT
SEE
TEXT
SEE
R4
0Ω
VPSR
VPSR
VREF
20
5
R7
0Ω
TEMP
VLVL
C15
0.1μF
C8
100pF
19
6
TEXT
SEE
CLPA
CLPB
18
7
TEXT
TEXT
SEE
SEE
VSTA
VSTB
17
OUTN
OUTB
8
OUTA
FBKA
OUTP
FBKB
NC
NC
16
15
14
13
12
11
10
9
0Ω
R12
R8
0Ω
R10
R21
R9
0Ω
0Ω
R20
0Ω
0Ω
1kΩ
1kΩ
R1
R2
OUTPUT
VOLTAGE B
SETPOINT
VOLTAGE B
DIFF OUT +
DIFF OUT –
OUTPUT
VOLTAGE B
SETPOINT
VOLTAGE B
Rev. PrB | Page 14 of 27
While the input can be reactively matched, in general this is not
necessary. An external 52.3 Ω shunt resistor (connected on the
signal side of the input coupling capacitors, as shown in
Figure 11) combines with the relatively high input impedance
to give an adequate broadband 50 Ω match.
The coupling time constant, 50 × C
corner with a 3 dB attenuation at f
C1 = C2 = C
corner will be ~68 kHz. In high frequency applications, f
should be as large as possible to minimize the coupling of
unwanted low frequency signals. In low frequency applications,
a simple RC network forming a low-pass filter should be added
at the input for similar reasons. This should generally be placed
at the generator side of the coupling capacitors, thereby
lowering the required capacitance value for a given high-pass
corner frequency.
TEMPERATURE SENSOR INTERFACE
The ADL5519 provides a temperature sensor output capable of
driving about 1.6 mA. The temperature scaling factor of the
output voltage is approximately 2 mV/°C. The typical absolute
voltage at 25°C is ~620 mV.
INTERNAL
VPSA
INHA
C
Figure 13. TEMP Interface Simplified Schematic
INLA
. Using the typical value of 47 nF, this high pass
18.7kΩ
V PTAT
Figure 12. Single Channel Input Interface
5pF
18.7kΩ
Preliminary Technical Data
5pF
CURRENT
STAGE
Gm
COMR
VPSR
HP
C
/2, forms a high-pass
2kΩ
= 1/(2π × 50 × C
12kΩ
4kΩ
A = 9dB
STAGE
FIRST
OFFSET
COMP
GAIN
TEMP
C
), where
HP