MAX2065 MAXIM [Maxim Integrated Products], MAX2065 Datasheet - Page 23

• Manufacturer Part Number: MAX2065
• Description: 50MHz to 1000MHz High-Linearity, Serial/ Parallel-Controlled Analog/Digital VGA
• Manufacturer: MAXIM [Maxim Integrated Products]

The MAX2065 features an optional +3.3V supply voltage
operation with slightly reduced linearity performance.
The pin configuration of the MAX2065 has been opti-
mized to facilitate a very compact physical layout of the
device and its associated discrete components.
The exposed paddle (EP) of the MAX2065’s 40-pin thin
QFN-EP package provides a low thermal-resistance
path to the die. It is important that the PCB on which the
MAX2065 is mounted be designed to conduct heat
from the EP. In addition, provide the EP with a low-
inductance path to electrical ground. The EP must be
soldered to a ground plane on the PCB, either directly
or through an array of plated via holes.
To reduce amplitude overshoot during digital attenua-
tor state change, connect a bandpass filter (parallel
LC type) from ATTEN2_OUT (pin 23) to ground. L =
18nH and C = 47pF are recommended for 169MHz
operation (Figure 2). Contact the factory for recom-
mended components for other operating frequencies.
Table 6. Typical Application Circuit Component Values (LC Mode)
R2 (+3.3V applications only)
R3 (+3.3V applications only)
R4 (+5V applications and
C3, C4, C6, C8, C9, C10
using internal DAC only)
C1, C2, C7, C11
DESIGNATION
C12, C13
R1A
U1
L1
R1
Amplitude Overshoot Reduction
50MHz to 1000MHz High-Linearity, Serial/
+5V and +3.3V Supply Voltage
______________________________________________________________________________________
Parallel-Controlled Analog/Digital VGA
Layout Considerations
VALUE
1000pF
470nH
0.01µF
150pF
47kΩ
10nF
24Ω
1kΩ
2kΩ
—
40-pin thin QFN-EP
(6mm x 6mm)
SIZE
0402
0402
0402
1008
0402
0402
0402
0402
0402
Figure 2. Bandpass Filter to Reduce Amplitude Overshoot
Murata Mfg. Co., Ltd.
Murata Mfg. Co., Ltd.
Murata Mfg. Co., Ltd.
Murata Mfg. Co., Ltd.
26
25
24
23
22
21
Maxim Integrated
Panasonic Corp.
Panasonic Corp.
Panasonic Corp.
Products, Inc.
Coilcraft, Inc.
GND
GND
GND
ATTEN2_OUT
GND
VCC_AMP
VENDOR
Vishay
C6
C7
C8
V
CC
C0G ceramic capacitor
C0G ceramic capacitor
1008CS-471XJLC
DESCRIPTION
MAX2065ETL+
L
X7R
X7R
1%
1%
1%
1%
C
23