ONET8541T_16 Datasheet, PDF (3/17 Pages) Texas Instruments – 11.3 Gbps Limiting Transimpedance Amplifier

ONET8541T
www.ti.com
SLLSE85A – JULY 2011 – REVISED AUGUST 2011
BOND PAD ASSIGNMENT
The ONET8541T is available in die form. The locations of the bondpads are shown in Figure 2.
GND 1
OUT+ ₂
GND 3
18
17
8541T
M
16
15
14
GND
OUT–
GND
VCC_OUT
VCC_IN
4
13
5
12
6 7 8 9 10 11
RSSI_EB
RSSI_IB
Figure 2. Bond Pad Assignment of ONET8541T
PIN FUNCTIONS
NAME
PIN
NO.
TYPE
DESCRIPTION
GND
1, 3, 6, 10
14, 16 – 18
Supply
Circuit ground. All GND pads are connected on die. Bonding all pads is optional; however, for
optimum performance a good ground connection is mandatory.
OUT+
2
Analog Non-inverted CML data output. On-chip 50Ω back-terminated to V_CC.
output
VCC_OUT
4
Supply 2.97V–3.63V supply voltage for the voltage and CML amplifiers.
VCC_IN
5
Supply 2.97V–3.63V supply voltage for input TIA stage.
FILTER
IN
7, 9
Analog
Bias voltage for photodiode cathode. These pads are internally connected to an 220Ω resistor to
V_CC and a filter capacitor to ground (GND).
8
Analog input Data input to TIA (photodiode anode).
NC
11
No Connect Do not connect
RSSI_IB
12
RSSI_EB
13
OUT–
15
Analog
output
Analog
output
Analog
output
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 – 0.65V. If the RSSI feature is not used this pad should be left open.
Optional use when operated with external PD bias (e.g. 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 – 0.65V. If the RSSI feature is not used this pad should be left open.
Inverted CML data output. On-chip 50Ω back-terminated to V_CC.
Copyright © 2011, Texas Instruments Incorporated
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