- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄24829 > 935287961112 (NXP SEMICONDUCTORS) DATACOM, INTERFACE CIRCUIT, PDSO8 PDF資料下載
參數(shù)資料
| 型號： | 935287961112 |
| 廠商： | NXP SEMICONDUCTORS |
| 元件分類： | 網(wǎng)絡(luò)接口 |
| 英文描述： | DATACOM, INTERFACE CIRCUIT, PDSO8 |
| 封裝： | 3.90 MM, PLASTIC, MS-012, SOT96-1, SOP-8 |
| 文件頁數(shù)： | 17/22頁 |
| 文件大小： | 222K |
| 代理商： | 935287961112 |
2003 Oct 14
4
Philips Semiconductors
Product specication
High speed CAN transceiver
TJA1040
FUNCTIONAL DESCRIPTION
Operating modes
The TJA1040 provides two modes of operation which are
selectable via pin STB. See Table 1 for a description of the
modes of operation.
Table 1
Operating modes
NORMAL MODE
In this mode the transceiver is able to transmit and receive
data via the bus lines CANH and CANL. See Fig.1 for the
block diagram. The differential receiver converts the
analog data on the bus lines into digital data which is
output to pin RXD via the multiplexer (MUX). The slope of
the output signals on the bus lines is fixed and optimized
in a way that lowest ElectroMagnetic Emission (EME) is
guaranteed.
STANDBY MODE
In this mode the transmitter and receiver are switched off,
and the low-power differential receiver will monitor the bus
lines. A HIGH level on pin STB activates this low-power
receiver and the wake-up filter, and after tBUS the state of
the CAN bus is reflected on pin RXD.
The supply current on VCC is reduced to a minimum in
such a way that ElectroMagnetic Immunity (EMI) is
guaranteed and a wake-up event on the bus lines will be
recognized.
In this mode the bus lines are terminated to ground to
reduce the supply current (ICC) to a minimum. A diode is
added in series with the high-side driver of RXD to prevent
a reverse current from RXD to VCC in the unpowered state.
In normal mode this diode is bypassed. This diode is not
bypassed in standby mode to reduce current consumption.
Split circuit
Pin SPLIT provides a DC stabilized voltage of 0.5VCC.Itis
turned on only in normal mode. In standby mode pin SPLIT
is floating. The VSPLIT circuit can be used to stabilize the
recessive common-mode voltage by connecting pin SPLIT
to the centre tap of the split termination (see Fig.4). In case
of a recessive bus voltage <0.5VCC due to the presence of
an unsupplied transceiver in the network with a significant
leakage current from the bus lines to ground, the split
circuit will stabilize this recessive voltage to 0.5VCC. So a
start of transmission does not cause a step in the
common-mode signal which would lead to poor
ElectroMagnetic Emission (EME) behaviour.
Wake-up
In the standby mode the bus lines are monitored via a
low-power differential comparator. Once the low-power
differential comparator has detected a dominant bus level
for more than tBUS, pin RXD will become LOW.
Over-temperature detection
The output drivers are protected against over-temperature
conditions. If the virtual junction temperature exceeds the
shutdown junction temperature Tj(sd), the output drivers will
be disabled until the virtual junction temperature becomes
lower than Tj(sd) and TXD becomes recessive again.
By including the TXD condition, the occurrence of output
driver oscillation due to temperature drifts is avoided.
TXD dominant time-out function
A ‘TXD dominant time-out’ timer circuit prevents the bus
lines from being driven to a permanent dominant state
(blocking all network communication) if pin TXD is forced
permanently LOW by a hardware and/or software
application failure. The timer is triggered by a negative
edge on pin TXD.
If the duration of the LOW level on pin TXD exceeds the
internal timer value (tdom), the transmitter is disabled,
driving the bus lines into a recessive state. The timer is
reset by a positive edge on pin TXD. The TXD dominant
time-out time tdom defines the minimum possible bit rate of
40 kBaud.
Fail-safe features
Pin TXD provides a pull-up towards VCC in order to force a
recessive level in case pin TXD is unsupplied.
Pin STB provides a pull-up towards VCC in order to force
the transceiver into standby mode in case pin STB is
unsupplied.
In the event that the VCC is lost, pins TXD, STB and RXD
will become floating to prevent reverse supplying
conditions via these pins.
MODE
PIN
STB
PIN RXD
LOW
HIGH
normal
LOW
bus dominant
bus recessive
standby
HIGH
wake-up request
detected
no wake-up
request detected
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| 935287961118 | DATACOM, INTERFACE CIRCUIT, PDSO8 |
| 935287961518 | DATACOM, INTERFACE CIRCUIT, PDSO8 |
| 935268735112 | DATACOM, INTERFACE CIRCUIT, PDSO8 |
| 935268735118 | DATACOM, INTERFACE CIRCUIT, PDSO8 |
| 935268750118 | LOW SKEW CLOCK DRIVER, 4 TRUE OUTPUT(S), 0 INVERTED OUTPUT(S), PDSO8 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| 9352-879-67118 | 制造商:NXP Semiconductors 功能描述:DATACOM, INTERFACE CIRCUIT, PDSO8 |
| 935288287551 | 制造商:NXP Semiconductors 功能描述:- Trays |
| 935288287557 | 制造商:NXP Semiconductors 功能描述:- Trays |
| 935288465027 | 制造商:NXP Semiconductors 功能描述:IC SMARTCARD RTC OSC COUNTER |
| 935288948115 | 制造商:NXP Semiconductors 功能描述:IC ANALOG SWITCH SP3T 10XQFN |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。