MAX2208EBS-T Maxim Integrated Products, MAX2208EBS-T Datasheet - Page 5

• Manufacturer Part Number: MAX2208EBS-T
• Description: RF Detector CDMA Power Detector r RF Power Detectors
• Manufacturer: Maxim Integrated Products

Specifications of MAX2208EBS-T

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The MAX2205–MAX2208 have internal termination
resistors for use with directional couplers. The applica-
tion circuit is shown in Figure 1. The output of the
detector goes to an op amp in an analog GSM power-
control scheme, or to an ADC in other systems such as
TDMA or discrete-time GSM power control.
The MAX2205 has high-input impedance for use with
high-value resistive tapping from a CDMA power ampli-
fier. This coupling method is the lowest cost and lowest
loss when used with an isolator. The application circuit
is shown in Figure 2. Connect C
MAX2205 output to GND to reduce residual amplitude
ripple. For IS98A reverse channel signal with peak-to-
avg ratio of 3.9dB, a 1.5nF capacitor gives 43mV
ple at 28dBm PA output and 390µs response time. For
CDMA2000 (pilot + DCCH) with peak-to-avg ratio of
5.4dB, the ripple is about 65mV
The MAX2205 input impedance is listed in Table 1.
As with any RF circuit, the layout of the MAX2205–
MAX2208 circuits affects performance. Use a short
50Ω line at the input with multiple ground vias along the
length of the line. The input capacitor and resistor
should be placed as close to the IC as possible. The
V
the IC with multiple vias connecting the capacitor to
ground. Refer to the MAX2205–MAX2208 EV kit data
sheet for a sample layout and details.
Figure 1. MAX2206/MAX2207/MAX2208 Typical Application
Circuit
CC
PA
input should be bypassed as close as possible to
Applications Information
COUPLER
_______________________________________________________________________________________
50Ω
DETECTOR
MAX2206
MAX2207
MAX2208
PEAK
P-P
at 26dBm PA output.
FILTER
Layout
OR OP AMP
TO ADC
from the
RF Power Detectors in UCSP
TO ANT
P-P
rip-
The UCSP is a unique package that greatly reduces
board space compared to other packages. UCSP relia-
bility is integrally linked to the user’s assembly methods,
circuit board material, and usage environment. The user
should closely review these areas when considering
using a UCSP. This form factor might not perform equally
to a packaged product through traditional mechanical
reliability tests. Performance through operating life test
and moisture resistance remains uncompromised, as it
is determined primarily by the wafer-fabrication process.
Mechanical stress performance is a greater considera-
tion for a UCSP. UCSP solder-joint contact integrity must
be considered because the package is attached through
direct solder contact to the user’s PC board. Testing
done to characterize the UCSP reliability performance
shows that it is capable of performing reliably through
environmental stresses. Results of environmental stress
tests and additional usage data and recommendations
are detailed in the UCSP application note, which can be
found on Maxim’s website, www.maxim-ic.com.
TRANSISTOR COUNT: 344
Figure 2. MAX2205 Typical Application Circuit
PA
680Ω
47pF
DETECTOR
MAX2205
PEAK
UCSP Reliability
Chip Information
CIRCULATOR
ISOLATOR/
C
FILTER
TO ADC
TO ANT
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