Datasheet
INN
INP
RX_ANA_GND
VCM
DNC
(1)
DNC
BG
VSS
TX_REF
DNC
CLKOUT
RESET
ADC_RDY
SPISTE
SPISIMO
SPISOMI
SCLK
PD_ALM/ADC Reset
LED_ALM
DIAG_END
1
2
3
4
5
6
7
8
9
10
30
29
28
27
26
25
24
23
22
21
TX_CTRL_SUP
11 12 13 14 15 16 17 18 19 20
40 39 38 37 36 35 34 33 32 31
RX_ANA_GND
LED_DRV_GND
RX_ANA_SUP
LED_DRV_GND
XIN
TXN
XOUT
TXP
RX_ANA_GND
LED_DRV_GND
RXOUTP
LED_DRV_SUP
RXOUTN
LED_DRV_SUP
RX_ANA_SUP
RX_DIG_GND
RX_DIG_GND
AFE_
PDN
RX_DIG_SUP
AFE4490
www.ti.com
SBAS602F –DECEMBER 2012–REVISED OCTOBER 2013
PIN CONFIGURATION
RHA PACKAGE
QFN-40
(Top View)
(1) DNC = Do not connect.
PIN DESCRIPTIONS
NAME NO. FUNCTION DESCRIPTION
Output signal that indicates ADC conversion completion.
ADC_RDY 28 Digital
Can be connected to the interrupt input pin of an external microcontroller.
AFE-only power-down input; active low.
AFE_PDN 20 Digital
Can be connected to the port pin of an external microcontroller.
Decoupling capacitor for internal band-gap voltage to ground
BG 7 Reference
(2.2-µF decoupling capacitor to ground, expected voltage = 1.0 V).
Buffered 4-MHz output clock output.
CLKOUT 30 Digital
Can be connected to the clock input pin of an external microcontroller.
Output signal that indicates completion of diagnostics.
DIAG_END 21 Digital
Can be connected to the port pin of an external microcontroller.
DNC
(1)
5, 6, 10 — Do not connect these pins. Leave as open-circuit.
INN 1 Analog Receiver input pin. Connect to photodiode anode.
INP 2 Analog Receiver input pin. Connect to photodiode cathode.
LED_DRV_GND 12, 13, 16 Supply LED driver ground pin, H-bridge. Connect to common board ground.
LED driver supply pin, H-bridge. Connect to an external power supply capable of supplying the
LED_DRV_SUP 17, 18 Supply
large LED current, which is drawn by this supply pin.
Output signal that indicates an LED cable fault.
LED_ALM 22 Digital
Can be connected to the port pin of an external microcontroller.
(1) Leave pins as open circuit. Do not connect.
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 11
Product Folder Links: AFE4490