MAX3968 Maxim Integrated Products, MAX3968 Datasheet - Page 5

• Manufacturer Part Number: MAX3968
• Description: (MAX3964 - MAX3968) 125Mbps to 266Mbps Limiting Amplifiers
• Manufacturer: Maxim Integrated Products

QSOP
19, 20
Limiting Amplifiers with Loss-of-Signal Detector
9, 10
11
12
13
14
15
16
17
18
—
1
2
3
4
5
6
7
8
PIN
6, 7, 8
17, 18
QFN
EP
19
20
10
11
12
13
14
15
16
—
1
2
3
4
5
9
_______________________________________________________________________________________
SQUELCH
Exposed
FILTER
NAME
GNDO
OUT+
V
LOS+
V
OUT-
GND
LOS-
RSSI
CZN
SUB
CZP
V
V
IN+
Pad
INV
IN-
CCO
CCO
CC
TH
+3.0V to +5.5V, 125Mbps to 266Mbps
Squelch Input. The squelch function disables the data outputs by forcing OUT- low and OUT+
high during a loss-of-signal condition. Connect to GND or leave unconnected to disable.
Connect to V
Output of Internal Op Amp that Sets Loss-of-Signal Threshold Voltage (Figure 1). Connect a
resistor from V
desired threshold voltage.
Inverting Input of Internal Op Amp that Sets Loss-of-Signal Threshold Voltage (Figure 1).
Connect a resistor from V
program the desired threshold voltage.
Filter Output of Full-Wave Logarithmic Detectors (FWDs). The FWD outputs are summed
together at FILTER to generate the received-signal-strength indicator (RSSI). Connect a
capacitor from FILTER to V
Received-Signal-Strength Indicator Output. The analog DC voltage at RSSI indicates the input
signal power. The RSSI output is reduced approximately 120mV when LOS+ is asserted.
Inverting Data Input
Noninverting Data Input
Substrate. Connect to ground.
Ground
Auto-Zero Capacitor Input. Connect a capacitor between CZP and CZN to determine the offset-
correction-loop bandwidth.
Auto-Zero Capacitor Input. Connect a capacitor between CZP and CZN to determine the offset-
correction-loop bandwidth.
Output Buffer Supply Voltage. Connect to the same potential as V
separately.
Noninverting PECL Data Output. Terminate with 50Ω to (V
Inverting PECL Data Output. Terminate with 50Ω to (V
Inverting Loss-of-Signal Output. LOS- is asserted low when input power drops below the LOS
threshold. For the MAX3964/MAX3968, this pin is PECL compatible and should be terminated
with 50Ω to (V
termination.
Noninverting Loss-of-Signal Output. LOS+ is asserted high when input power drops below the
LOS threshold. For the MAX3964/MAX3968, this pin is PECL compatible and should be
terminated with 50Ω to (V
require termination.
MAX3964/MAX3968: This pin can be left open or connected to the positive supply.
MAX3965: This pin must be connected to ground.
+3.0V to +5.5V Supply Voltage
Connect the exposed pad to board ground for optional electrical and thermal performance.
CC
CC
TH
to enable squelching.
- 2V). For the MAX3965, this outpt is TTL compatible and does not require
to INV and from INV to ground (minimum resistance 100kΩ) to program the
TH
CC
CC
to INV and from INV to ground (minimum resistance 100kΩ) to
- 2V). For the MAX3965, this output is TTL compatible and does not
for proper operation.
FUNCTION
CC
- 2V).
CC
- 2V).
CC
, but filter V
Pin Description
CCO
and V
CC
5