Qh7937 price and stock

Содержание

1 Results for a part that might be similar to «qh7937»: QH130Note: This part list is based upon the part number. Please verify all specifications of the parts below.
2 QH7938 Datasheet Download — ETC
3 HT7937 Datasheet Download — Holtek Semiconductor
4 Results for a part that might be similar to «qh7938»: QH-3/8Note: This part list is based upon the part number. Please verify all specifications of the parts below.

Results for a part that might be similar to «qh7937»: QH130Note: This part list is based upon the part number. Please verify all specifications of the parts below.

Quest Components

Part #	Manufacturer	Description	Stock	Price	Buy
QH130	Square D by Schneider Electric	PLUG-ON CIRCUIT BREAKER, 30A, 120/240 V, 50-60 HZ	1

Newark element14 Authorized Distributor

Part #	Manufacturer	Description	Stock	Price	Buy
QH130 DISTI # 80C3303	Square D by Schneider Electric	MINIATURE CIRCUIT BREAKER 120/240V 30A RoHS: Not Compliant Min Qty: 1 Container: Bulk

Part #

Manufacturer

Description

Stock

Price

Buy

QH130

DISTI #
80C3303

Square D by Schneider Electric

MINIATURE CIRCUIT BREAKER 120/240V 30A

RoHS:

Not Compliant

Min Qty:
1

Container:
Bulk

QH7938 Datasheet Download — ETC

Номер произв

QH7938

Описание

Primary side feedback dimmable single-stage active PFC LED constant current control chip

Производители

ETC

логотип

1Page

No Preview Available !

QH7938

可调光原边反馈单级有源 PFC LED 恒流控制芯片

概述
特点

QH7938是一款单级、带有源功率因数校正的高精度

原边反馈 LED 恒流控制芯片，带调光控制功能，适

用于 85Vac-265Vac 全范围输入电压的反激式隔离

或升降压型非隔离 LED 恒流电源。QH7938集成有源

功率因数校正电路，可以实现很高的功率因数和很
低的总谐波失真。由于工作在电感电流临界连续模

式，功率 MOS 管处于零电流开通状态，开关损耗得

以减小，同时变压器的利用率也较高。

Даташит bp2836d pdf ( datasheet )

QH7938 采用专有的电流采样机制，工作于原边反馈

模式，无需次级反馈电路，即可实现高精度输出恒
流控制，节约了系统成本和体积，提高了系统的可
靠性。

QH7938 采用专利的线电压和负载补偿技术，可以达

到优异的线电压调整率和负载调整率。线电压补偿
系数还可以通过外部元件灵活调整。
内置多重保护功能来加强系统可靠性，包括

LED 开路保护、LED 短路保护、芯片供电过压保护、

欠压保护、电流采样电阻开路保护和逐周期限流等。

所有的保护都具有自动重启功能。另外，QH7938具

有过热调节功能，在驱动电源过热时减小输出电流，

以提高系统的可靠性。QH7938的过热调节温度可以

Даташит mt7201 pdf ( datasheet )

通过外部电阻设定。

 单级、有源功率因数校正，高 PF 值，低 THD

 原边反馈恒流控制，无需次级反馈电路

 带调光接口

 ±3% LED 输出电流精度

 优异的线电压调整率和负载调整率

 电感电流临界连续模式

 超低 (28uA) 启动电流

 FB 反馈电阻值高，功耗低

Ремонтируем светодиодную лампу самостоятельно

 LED 开路短路保护

 电流采样电阻开路保护

 逐周期原边电流限流

 芯片供电过压欠压保护

 自动重启功能

 过热调节功能

 过热调节温度可外部设定

 采用 SOP-8 封装

应用

 GU10/E27 LED 球泡灯、射灯

 LED PAR30、PAR38 灯

 LED 日光灯

 其它 LED 照明

典型应用

NP NS

QH7938

2 VCC

RTH 8

3 FB

DIM 7

1 COMP

6 GND

GATE 5

CS 4

图 1 QH7938 典型应用图

No Preview Available !

定购信息
定购型号

QQqH7938

QH7938

可调光原边反馈单级有源 PFC LED 恒流控制芯片

封装
SOP8
温度范围

-40 ℃ 到 105 ℃

包装形式
编带

2,500 颗盘

打印
QH7938
XYY
管脚封装
管脚描述
管脚号
1
2
3
4
5
6
7
8
COMP
RTH

VCC QH7938 DIM

FB GND
CS GATE

图 2 管脚封装图

XXXXXY: lot code
X: Year

YY：Week

管脚名称
COMP
VCC
FB
CS
GATE
GND
DIM
RTH
描述
环路补偿点
芯片电源
辅助绕组反馈信号采样端
电流采样端，接采样电阻到地

外部功率 MOS 管栅极驱动

芯片信号和功率地
调光输入端，不调光时可悬空
过热调节温度设置端，接电阻到地，不设置时可悬空
2

No Preview Available !

可调光原边反馈单级有源 PFC LED 恒流控制芯片

极限参数(注 1)

符号

VCC

电源电压
参数
参数范围

-0.3~25

单位
V

ICC_MAX

VCC引脚最大钳位电流

5 mA

COMP 环路补偿点

-0.3~6

FB 辅助绕组的反馈端

-0.3~6

CS 电流采样端

-0.3~6

DIM 调光输入端

-0.3~6

RTH 过热调节温度调整端

-0.3~6

GATE 外部功率 MOS 管栅极驱动电压

-0.3~25

PDMAX 功耗(注 2)

0.45
W

θ JA PN 结到环境的热阻

145 ℃/W

TJ 工作结温范围

-40 to 150
℃

TSTG 储存温度范围

-55 to 150
℃

ESD (注 3)

2 KV

注 1：最大极限值是指超出该工作范围，芯片有可能损坏。推荐工作范围是指在该范围内，器件功能正常，但并不完全

保证满足个别性能指标。电气参数定义了器件在工作范围内并且在保证特定性能指标的测试条件下的直流和交流电参数
规范。对于未给定上下限值的参数，该规范不予保证其精度，但其典型值合理反映了器件性能。

注 2：温度升高最大功耗一定会减小，这也是由 TJMAX, θ JA,和环境温度 TA 所决定的。最大允许功耗为 PDMAX = (TJMAX — TA)/

θ JA 或是极限范围给出的数字中比较低的那个值。

注 3：人体模型，100pF 电容通过 1.5KΩ 电阻放电。

推荐工作范围
符号

VCC

参数
电源电压
参数范围

8.5 ~ 17

单位
V
3

Всего страниц

9 Pages

Скачать PDF

HT7937 Datasheet Download — Holtek Semiconductor

Номер произв

HT7937

Описание

Built-in OVP White LED Step-up Converter

Производители

Holtek Semiconductor

логотип

1Page

No Preview Available !

HT7937
Built-in OVP White LED Step-up Converter
Features

· Integrated open-circuit protection

· Over voltage protection

· Up to 84% efficiency at VIN=3V, 3LEDs,

ILED= 20mA

· 1.2MHz fixed switching frequency

· Low standby current: 0.1mA (typ.) (VSHDN=0V)

· Matches LED current

· Small value inductor and capacitors

· Small outline SOT23-6 package

Applications

· Cellular phones

· PDAs

· DSCs

· Handheld devices

· White LED display backlighting

General Description
The HT7937 is high efficiency boost converter with a
constant current output to provide back light functions in
handheld devices. Applications with series connected
LEDs ensure constant and identical LED currents re-
sulting in uniform brightness. A continuous LED output
current is setup using the FB pin regulated voltage

across an external sense resistor, RFB connected be-

tween the FB pin and ground. The integrated open load
protection circuitry prevents damage resulting from an
Block Diagram
open circuit condition. The low 95mV feedback voltage
minimises power losses in the current setting resistor
which improves efficiency. The HT7937 has a high
switching frequency of up to 1.2MHz which permits the
use of lower value extremely small outline inductor and
filter capacitor.
The HT7937 is supplied in a space-saving, 6-lead
SOT23-6 package type.
www.DataSheet4U.com
SHDN
FB
28V
C o n tro l
L o g ic
O VP
SW
95m V
å
1 .2 M H z
O s c illa to r
GND
V IN
Rev 1.10
1 January 18, 2010

No Preview Available !

HT7937
Pin Assignment
S O T 2 3 -6
V IN O V P S H D N
6 54
T o p V ie w
1 23
SW G N D FB
Pin Description
Pin No. Pin Name
Description
1 SW Switching pin
2 GND Ground pin
3
FB
Output voltage sense node. Connect the cathode of the LED to this pin. A resistor from this
pin to ground sets the LED current. Internally compares to 95mV (Typ.).
4
SHDN
Shutdown device pin. Connect to 1.5V or higher to enable device (ON), 0.3V or lower to dis-
able device (OFF).
5 OVP For over voltage protection connect to the output.
6 VIN Input voltage pin. 2.5V to 5.5V for internal circuitry.
Absolute Maximum Ratings
Input Voltage……………………………………………………..6V
FB Voltage ………………………………………………………..6V
OVP Voltage ……………………………………………………36V

Maximum Junction Temperature……………………..125°C

SW Voltage……………………………………………………..36V
SHDN ………………………………………………………………6V

Operating Temperature Range ……………-40°C to 85°C

Note: These are stress ratings only. Stresses exceeding the range specified under ²Absolute Maximum Ratings² may

cause substantial damage to the device. Functional operation of this device at other conditions beyond those listed
in the specification is not implied and prolonged exposure to extreme conditions may affect device reliability.
www.DataSheet4U.com
Rev 1.10
2 January 18, 2010

No Preview Available !

HT7937
Electrical Characteristics

VSHDN=3V; VIN=3V; Ta=25°C (Unless otherwise specified)(Note)

Symbol
Parameter

VIN Input Voltage

IIN Supply Current

VFB

fOSC

RDS(ON)

ISW(OFF)

VIH

VIL

VOVP

Feedback Voltage
Switching Frequency
Maximum Duty Cycle
SW On Resistance
Switch Leakage Current
SHDN Voltage High
SHDN Voltage Low
OVP Threshold
Test Conditions
¾
Switching
Non-switching

VSHDN= 0V

3 LEDs
Measurement at SW pin
No load
¾
¾
¾
¾
Min. Typ. Max. Unit
2.5 3 5.5 V

¾ 1.0 1.25 mA

¾ 50 100 mA

¾ 0.1 1 mA

85 95 105 mV
0.8 1.2 1.6 MHz

85 90 ¾ %

¾ 1.4

5
W

¾ 0.1 1 mA

1.5 ¾ ¾ V

¾ ¾ 0.3 V

23 28 33
V

Note: Specifications are production tested at Ta=25 degree. Specifications over -40 to 85 degree operating

temperature range are assured by design, characterization.
www.DataSheet4U.com
Rev 1.10
3 January 18, 2010

Всего страниц

13 Pages

Скачать PDF

Results for a part that might be similar to «qh7938»: QH-3/8Note: This part list is based upon the part number. Please verify all specifications of the parts below.

Farnell element14 Authorized Distributor

Part #	Manufacturer	Description	Stock	Price	Buy
QH-3/8 DISTI # 3432682	Festo	BALL VALVE, G3/8, 180DEG C RoHS: Compliant Min Qty: 1 Container: Each	2

Part #

Manufacturer

Description

Stock

Price

Buy

QH-3/8

DISTI #
3432682

Festo

BALL VALVE, G3/8, 180DEG C

RoHS:

Compliant

Min Qty:
1

Container:
Each

Newark element14 Authorized Distributor

Part #	Manufacturer	Description	Stock	Price	Buy
QH-3/8 DISTI # 78AH7421	Festo	BALL VALVE, G3/8, 180DEG C ROHS COMPLIANT: YES RoHS: Compliant Min Qty: 1 Container: Bulk	2	250 $28.5900 100 $29.5900 50 $30.5900 25 $32.9300 1 $35.9400 See More

Part #

Manufacturer

Description

Stock

Price

Buy

QH-3/8

DISTI #
78AH7421

Festo

BALL VALVE, G3/8, 180DEG C ROHS COMPLIANT: YES

RoHS:

Compliant