参数资料
型号: PT7756C
厂商: TEXAS INSTRUMENTS INC
元件分类: 稳压器
英文描述: 15 A SWITCHING REGULATOR, 400 kHz SWITCHING FREQ-MAX, SMA27
封装: SIP-27
文件页数: 4/7页
文件大小: 149K
代理商: PT7756C
For technical support and more information, see inside back cover or visit www.ti.com/powertrends
Application Notes continued
Using the Standby Function on the PT7750
“Big Hammer III” Programmable ISRs
For applications requiring output voltage On/Off control,
the PT7750 “Big Hammer” ISRs incorporate a standby
function1 . This feature may be used for power-up/shut-
down sequencing, and to change the output voltage while
input power is applied. See related notes: “Pin-coded Out-
put Voltage Adjustment on the ‘Big Hammer III’ Series
ISRs.”
The standby function is provided by the STBY* control,
pin 5. If pin 5 is left open-circuit the regulator operates
normally, providing a regulated output whenever a valid
supply voltage is applied to V
in (pins 7-11) with respect to
GND (pins 13-19). Connecting pin 5 to ground 2 will set
the regulator output to zero volts 3 . This places the regu-
lator in standby mode, and reduces the input current to
typically 30mA (50mA max). If a ground signal is applied
to pin 5 prior to power-up, the regulator output will be
held at zero volts during the period that input power is
applied.
The standby input must be controlled with an open-col-
lector (or open-drain) discrete transistor (See Figure 1).
Table 1 gives the threshold requirements.
Table 1 Inhibit Control Threshold 2
Parameter
Min
Max
Disable (VIL)
–0.1V
0.3V
Notes:
1. The Standby/Inhibit control logic is similar for all Power
Trends’ modules, but the flexibility and threshold
tolerances will be different. For specific information on
this function for other regulator models, consult the
applicable application note.
2. The Standby input on the PT7750 regulator series must be
controlled using an open-collector (or open-drain) discrete
transistor. Do Not use a pull-up resistor. The control input
has an open-circuit voltage of about 1.5Vdc. To set the
regulator output to zero, the control pin must be “pulled”
to less than 0.3Vdc with a low-level 0.1mA sink to ground.
3. When placed in the standby mode, the regulator output
discharges the output capacitance with a low impedance to
ground. If an external voltage is applied to the output, it
will sink current and possibly over-stress the part.
4. The turn-off time of Q
1, or rise time of the standby input
is not critical on the PT7750 series. Turning Q
1 off slowly,
over periods up to 100ms, will not affect regulator
operation. However, a slow turn-off time will increase
both the initial delay and rise-time of the output voltage.
Figure 1
Turn-On Time:
Turning Q
1 in Figure 1 off, removes the low-
voltage signal at pin 5 and enables the output. Following a
brief delay of 8-18ms, the output voltage of the PT7750 series
regulators rise to full regulation within 20ms 4 . Figure 2 shows
the typical output voltage waveform of a PT7751 following the
prompt turn-off of Q
1 at time t =0 secs. The output voltage in
Figure 1 is set to 5.0V by connecting VID0 (pin 1), VID3 (pin
4), and VID4 (pin 6) to the Remote Sense Gnd (pin 12)*. The
waveform in Figure 2 was measured with a 24V input source
voltage, and 10A resistive load.
Figure 2
C
out
+
C
in
+
+24V
COM
Inhibit
L
O
A
D
V
o
=5.0V
COM
Q1
BSS138
PT7750
64321
26
20-25
12
5
13-19
27
7-11
Vo
Vin
GND
SNS(+)
SNS(-)
Synch
Out
STBY
VID4 - VID0
* Consult the data sheet for details on other VID codes.
PT7750 Series
0
5
10
15
20
25
t (milli - secs)
Vin (2V/Div)
相关PDF资料
PDF描述
PT7771N1 32 A SWITCHING REGULATOR, 750 kHz SWITCHING FREQ-MAX, SMA27
PT7771N DC-DC REG PWR SUPPLY MODULE
PT7771A DC-DC REG PWR SUPPLY MODULE
PT7771C SWITCHING REGULATOR, PSMA27
PT7773N 32 A SWITCHING REGULATOR, 750 kHz SWITCHING FREQ-MAX, SMA27
相关代理商/技术参数
参数描述
PT7756N 功能描述:开关变换器、稳压器与控制器 6.6-12.8Vout 15A 24V Input Prog ISR RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel
PT7761 制造商:DATATRONIC 功能描述:
PT7761-5V 制造商:TI 制造商全称:Texas Instruments 功能描述:40-A Programmable Integrated Switching Regulator Module
PT7761A 功能描述:DC/DC转换器 1.3V to 3.5V 40-A 5V Input Prog ISR RoHS:否 制造商:Murata 产品: 输出功率: 输入电压范围:3.6 V to 5.5 V 输入电压(标称): 输出端数量:1 输出电压(通道 1):3.3 V 输出电流(通道 1):600 mA 输出电压(通道 2): 输出电流(通道 2): 安装风格:SMD/SMT 封装 / 箱体尺寸:
PT7761C 功能描述:REG 1.3-3.5V 40A 5VIN PROG SMD RoHS:否 类别:电源 - 板载 >> DC DC Converters 系列:PT7760 设计资源:Maxi/Mini/Micro Design Guide, Appl Manual 标准包装:1 系列:Maxi 类型:隔离 输出数:1 电压 - 输入(最小):43V 电压 - 输入(最大):110V Voltage - Output 1:15V Voltage - Output 2:- Voltage - Output 3:- 电流 - 输出(最大):* 电源(瓦) - 制造商系列:400W 电压 - 隔离:* 特点:* 安装类型:通孔 封装/外壳:模块 尺寸/尺寸:4.60" L x 2.20" W x 0.54" H(116.8mm x 55.9mm x 13.7mm) 包装:散装 工作温度:-55°C ~ 100°C 效率:* 电源(瓦特)- 最大:*