參數(shù)資料
型號(hào)： L4969
廠商： 意法半導(dǎo)體
英文描述： SYSTEM VOLTAGE REGULATOR WITH FAULT TOLERANT LOW SPEED CAN-TRANSCEIVER
中文描述： 系統(tǒng)電壓調(diào)節(jié)器容錯(cuò)低速的CAN收發(fā)器
文件頁(yè)數(shù)： 13/35頁(yè)
文件大小： 337K
代理商： L4969
13/35
L4969
1.4
A low power oscillator provides an internal clock. In sleep mode (Watchdog active) the output frequency is
250kHz, if the Watchdog function is not requested, the internal Oscillator is switched off.
In standby and operating mode the oscillator is running at 1MHz, and can be calibrated in a range from -16% to
+16% using the
μ
C-XTAL as a reference.
Oscillator
1.5
A triple function programmable watchdog is integrated to perform the following tasks:
– Wakeup Watchdog:
When in sleep or standby mode the watchdog can generate a wakeup condition after a programma-
ble period of time ranging from 80ms up to 45 minutes
– Startup Watchdog:
Upon V1 power-up or
μ
C failure during SPI supervision (see SW-Watchdog) a reset pulse is gener-
ated periodically every 320ms for 2.5ms until activity of the
μ
C is detected (SPI sequence) or no ac-
knowledge is received within 7 cycles (2.2sec). In this condition the device is forced into Sleep mode
until a Wakeup is detected and a startup cycle is reinitialized.
– Window Watchdog:
After passing the startup sequence, this watchdog request an acknowledge by the
μ
C via the SPI
within a programmable timing frame, ranging from 2.5 ... 5ms up to 20 ... 40ms. Upon a missing or
misplaced acknowledge the Startup Watchdog is initialized.
WatchdL4969og
1.6
Reset
1.6.1 Power-on Reset
Upon Power-on (VS > 3.5V), the internal reset forces the device into a predefined power-on state (see 1.1):
Standby #3:V1 on V2 off V3 off,CAN-Standby mode, ID-Filter disabled, Startup Watchdog active
With VS below 5V the regulator V1 will follow VS with minimum drop. The
μ
C retrieves a reset if V1 is dropping
below a programmable voltage level of either 4.5V (default) or 4.0V. The programmed state of the L4969 re-
mains unchanged. The act. low Resetpulse duration is fixed internally by an open-drain output stage to 1ms.
However, this time can be externally extended by an additional capacitance connect between NRESET and
GROUND which is then charged by the internal pull-up of typ. 120K. Depending on the Reset-Input-Threshold
of the uC (U
TR
), the reqired Capacitance for a typical t
D
can be calculated as follows:
C
EXT
= -t
D
/ (120E3 ln(1-U
TR
/V1))).
To obtain a reset-pulse duration of t
D
= 50ms with U
TR
/V1 = 0.5, a Capacitance of C
EXT
= -50E-3 / (120E3 ln
0.5) = 600nF is required.
Figure 4.
1.6.2
Upon detection of a V1 voltage level below a programmable voltage level of either 4.5V (default) or 4.0V,the
NRES-pin is pulled low. Since this undervoltage detection is additionally sampled periodically every ms, the
NRES low time will be extended by up to 1 ms if V1 was low (V1
UV
) at the sampling point (see below).
Undervoltage Reset
V1
120K
NRES
C
EXT
to Reset Input of uC
相關(guān)PDF資料
PDF描述
L4973D3 RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS
L4973D5 RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS
L4973V3 RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS
L4973V5 RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS
L4973 RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
L4969013TR 功能描述:低壓差穩(wěn)壓器 - LDO Triple w/Lo-Spd Tran RoHS:否 制造商:Texas Instruments 最大輸入電壓:36 V 輸出電壓:1.4 V to 20.5 V 回動(dòng)電壓（最大值）:307 mV 輸出電流:1 A 負(fù)載調(diào)節(jié):0.3 % 輸出端數(shù)量: 輸出類型:Fixed 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-20
L4969D 功能描述:線性穩(wěn)壓器 - 標(biāo)準(zhǔn) Triple w/Lo-Spd Tran RoHS:否 制造商:STMicroelectronics 輸出類型: 極性: 輸出電壓:1.8 V 輸出電流:150 mA 負(fù)載調(diào)節(jié): 最大輸入電壓:5.5 V 線路調(diào)整率: 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SOT-323-5L
L4969D013TR 功能描述:線性穩(wěn)壓器 - 標(biāo)準(zhǔn) Triple w/Lo-Spd Tran RoHS:否 制造商:STMicroelectronics 輸出類型: 極性: 輸出電壓:1.8 V 輸出電流:150 mA 負(fù)載調(diào)節(jié): 最大輸入電壓:5.5 V 線路調(diào)整率: 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SOT-323-5L
L4969MD 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:SYSTEM VOLTAGE REGULATOR WITH FAULT TOLERANT LOW SPEED CAN-TRANSCEIVER
L4969UR 功能描述:線性穩(wěn)壓器 - 標(biāo)準(zhǔn) BODY SMARTPOWER RoHS:否 制造商:STMicroelectronics 輸出類型: 極性: 輸出電壓:1.8 V 輸出電流:150 mA 負(fù)載調(diào)節(jié): 最大輸入電壓:5.5 V 線路調(diào)整率: 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SOT-323-5L
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*