- 您现在的位置：买卖IC网 > PDF目录67412 > FA7738N (FUJI ELECTRIC CO LTD) 5.5 A SWITCHING REGULATOR, 400 kHz SWITCHING FREQ-MAX, PDSO8 PDF资料下载
参数资料
| 型号： | FA7738N |
| 厂商： | FUJI ELECTRIC CO LTD |
| 元件分类： | 稳压器 |
| 英文描述： | 5.5 A SWITCHING REGULATOR, 400 kHz SWITCHING FREQ-MAX, PDSO8 |
| 封装： | SOP-8 |
| 文件页数： | 5/19页 |
| 文件大小： | 484K |
| 代理商： | FA7738N |
13
FA7738N/P
(6)
Short-circuit protection circuit for the timer latch
This unit incorporates a short-circuit protection
function for the timer latch that stops switching if the
output voltage remains low for a certain time due to
an output short-circuit or other trouble occurring in
the DC-DC converter circuit.
If the output voltage goes low due to an output
short-circuit or other trouble occurring in the DC-DC
converter circuit, the IN terminal of the reverse input
of the error amplifier will also go low. This voltage
is detected as 0.75 V (typically) or less, thus
activating the timer latch counter.
If a state of
insufficient output voltage continues unresolved and
exceeds delay time tprot (typically 90 msec) for
protecting against a timer latch short circuit, the unit
will judge the state as an error,
stop switching, and protect the circuit (Fig. 4).
The delay time for protecting the timer latch against a
short circuit is fixed inside the IC and cannot be
configured from outside.
Fig. 4
Recovering from latch stoppage requires resetting
by using an ENB terminal or setting the input voltage
to a level lower than the UVLO voltage.
(7) Overcurrent limitation circuit
The
system
incorporates
a
pulse-by-pulse
overcurrent limitation function that detects and limits
each main circuit current peak value of the internal
MOSFET.
The current that flows through the internal MOSFET
enters an overcurrent protection comparator as a
voltage signal based on the internal detection
resistor. If this signal is higher than the reference
voltage, the internal MOSFET is turned off and
limited so that no further current will flow.
This
limitation will be reset in the next cycle with its
output turned on again.
This limitation will be
repeated in each cycle along with overcurrent
limitation.
If the overcurrent state becomes even heavier and
the output voltage drops to a level lower than 75%
(typically) due to line impedance or some other
factor, the system will function in the same way as
timer latch short-circuit protection described in (6)
and be shut down.
(8) Overheat protection circuit
The system incorporates an overheat protection
function that stops switching if the IC overheats due
to overcurrent or other error.
If the IC chip reaches 135°C (typically), the system
stops switching.
If the chip temperature falls to
115°C, the system will resume switching. At such
time, the system will stop output, but the latching
function will not work.
(9) ON/OFF controller
Turning the output on and off is possible by applying
external signal from the ENB terminal.
To turn the output on, the ENB terminal can be set to
less than 1.0 V to initiate switching. At such time, a
soft start gradually increases the output voltage (Fig.
3).
The output can be turned off by either opening the
ENB terminal or applying an external voltage of at
least 2 V.
When the ENB terminal is open, the ENB terminal
will reach a voltage of about 5 V.
At such time, the IC will enter standby status, with
the internal control voltage (typically 3.0 V) shut
down, so that current consumption of the IC will
reach a maximum of 100 μA.
(10)
Low-voltage malfunction prevention circuit (UVLO)
The system incorporates a low-voltage malfunction
prevention circuit to prevent circuit malfunction in
case of a drop in power supply voltage.
Increasing the power supply voltage from 0 V will
cause the system to start running at a Vcc of 6.9 V
(typically). When the power supply voltage is low,
the output will be shut down at a Vcc of 5.9 V
(typically).
(11) Output circuit
The output circuit consists of P channel MOSFET,
with ON resistance of 0.8 (typically).
相关PDF资料 |
PDF描述 |
|---|---|
| FA7738P | 5.5 A SWITCHING REGULATOR, 400 kHz SWITCHING FREQ-MAX, PDIP8 |
| FAB2200UCX | 1.2 W, 2 CHANNEL, AUDIO AMPLIFIER, PBGA25 |
| FAN3850AUC19X | SPECIALTY CONSUMER CIRCUIT, PBGA6 |
| FAN4040DIS3-3.3 | 1-OUTPUT TWO TERM VOLTAGE REFERENCE, 3.3 V, PDSO3 |
| FAN4040CIS3-2.5 | 1-OUTPUT TWO TERM VOLTAGE REFERENCE, 2.5 V, PDSO3 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| FA7764 | 制造商:FUJI 制造商全称:Fuji Electric 功能描述:FUJI Power Supply Control IC |
| FA77B3 031660 | 制造商:Comair Rotron 功能描述:FAN 172MM 240VAC |
| FA77B3 31660 | 制造商:Comair Rotron 功能描述:FAN 171MM 240VAC |
| FA780 | 制造商:Black Box Corporation 功能描述:DB9/RJ12 MALE MODULAR ADAPTER, RED |
| FA781 | 制造商:Black Box Corporation 功能描述:DB9 Colored Modular Adapter (Unassembled), Male to RJ-11, 6-Wire, Green |
发布紧急采购，3分钟左右您将得到回复。