Philips Semiconductors Product specification
SA647Low-voltage digital IF receiver
2
1998 Aug 10 853–2037 19849
DESCRIPTION
The SA647 is a low-voltage high performance monolithic digital
system with high-speed RSSI incorporating a mixer, oscillator with
buffered output, two limiting intermediate frequency amplifiers, fast
logarithmic received signal strength indicator (RSSI), voltage
regulator, RSSI op amp and power down pin. The SA647 is
available in TSSOP (thin shrink small outline package).
The SA647 was designed for portable digital communication
applications and will function down to 2.7V. The limiter amplifier has
differential outputs with 2MHz small signal bandwidth. The RSSI
output has access to the feedback pin. This enables the designer to
level adjust the outputs or add filtering.
FEATURES
• V
CC
= 2.7 to 5.5V
• Low power receiver (5.3mA @ 3V)
• Power down mode (I
CC
= 110µA)
• Fast RSSI rise and fall times
• Extended RSSI range with temperature compensation
• RSSI op amp
• 2MHz limiter small signal bandwidth
• Filter matching (1.5kΩ)
• Differential limiter output
• Oscillator buffer
• TSSOP-20 package
APPLICATIONS
• NADC (North American Digital Cellular)
• Digital receiver systems
• Cellular radio
PIN CONFIGURATION
SR01456
MIX
OUT
IF AMP
IN
GND
LIM
IN
LIM OUT (+)
RF
IN+
RF
IN–
OSC E
OSC B
OSC
BUF
OUT
RSSI
RSSI FB
P
D
1
2
3
4
5
6
7
8
9
10
11
12
13
14
20
19
18
17
16
15
LIM OUT (-)
V
CC
IF AMP
DECOUP
IF AMP
DECOUP
IF AMP
OUT
LIM
DECOUP
LIM
DECOUP
Figure 1. Pin Configuration
ORDERING INFORMATION
DESCRIPTION TEMPERATURE RANGE ORDER CODE DWG #
20-Pin Plastic Thin Shrink Small Outline Package (Surface-mount) –40 to +85°C SA647DH SOT360–1
SR01727
OSCILLATOR
MIXER
+–
IF
AMP
20 19 18 17 16 15 14 13 12 11
123 45678 910
EB
LIMITER
V
CC
GND
FAST RSSI
+–
POWER
DOWN
Figure 2. Block Diagram
