ONET8531T_17 Datasheet, PDF (3/17 Pages) Texas Instruments – 11.3 Gbps Limiting Transimpedance Amplifier With RSSI

ONET8531T
www.ti.com
SLLS891B – FEBRUARY 2008 – REVISED AUGUST 2011
BOND PAD ASSIGNMENT
The ONET8531T is available in die form. The locations of the bond pads are shown in Figure 2.
19 18 17 16 15 14
13
GND
OUT+
VCC_OUT
VCC_IN
1
12 _OUT-
2
11 NC
10 RSSI_EB
3
9 RSSI_IB
4 5 6 78
Figure 2. ONET8531T Bond Pad Assignment
PIN
NAME
NO.
FILTER
5, 7
GND
4, 8,
13–19
IN
6
OUT+
1
OUT–
12
RSSI_EB
10
RSSI_IB
9
VCC_IN
3
VCC_OUT
2
PIN FUNCTIONS
TYPE
DESCRIPTION
Analog
Supply
Analog
input
Analog output
Analog output
Analog output
Analog output
Supply
Supply
Bias voltage for photodiode cathode. These pads are internally connected to an 220 Ω resistor to
V_CC and a filter capacitor to ground (GND).
Circuit ground. All GND pads are connected on die. Bonding all pads is optional; however for
optimum performance a good ground connection is mandatory.
Data input to TIA (photodiode anode).
Non-inverted CML data output. On-chip 50 Ω back-terminated to V_CC.
Inverted CML data output. On-chip 50 Ω back-terminated to V_CC.
Optional use when operated with external PD bias (for example, APD). Analog output current
proportional to the input data amplitude. Indicates the strength of the received signal (RSSI).
Connected to an external resistor to ground (GND). For proper operation, ensure that the voltage
at the RSSI pad does not exceed V_CC–0.65 V. If the RSSI feature is not used, this pad should be
left open.
Analog output current proportional to the input data amplitude. Indicates the strength of the
received signal (RSSI) if the photo diode is biased from the TIA. Connected to an external
resistor to ground (GND). For proper operation, ensure that the voltage at the RSSI pad does not
exceed V_CC–0.65 V. If the RSSI feature is not used, this pad should be left open.
2.97 V to 3.63 V supply voltage for input TIA stage.
2.97 V to 3.63 V supply voltage for the voltage and CML amplifiers.
Copyright © 2008–2011, Texas Instruments Incorporated
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