CS3843B datasheet(4/6 Pages) CHERRY

Nome de Peças	CS3843B

Descrição Electrónicos	Off-Line Current Mode PWM Control Circuit Off-Line Current Mode PWM Control Circuit

Download	6 Pages

Scroll/Zoom	100%

Fabricante Electrônico	CHERRY [Cherry Semiconductor Corporation]

Página de início	http://www.cherrycorp.com/

Logo

4 / 6 page

Undervoltage Lockout

During Undervoltage Lockout (Figure 1), the output driv-

er is biased to a high impedance state. VOUT should be

shunted to ground with a resistor to prevent output leak-

age current from activating the power switch.

PWM Waveform

To generate the PWM waveform, the control voltage from

the error amplifier is compared to a current sense signal

which represents the peak output inductor current

(Figure 2). An increase in VCC causes the inductor current

slope to increase, thus reducing the duty cycle. This is an

inherent feed-forward characteristic of current mode con-

trol, since the control voltage does not have to change

during changes of input supply voltage.

When the power supply sees a sudden large output cur-

rent increase, the control voltage will increase allowing

the duty cycle to momentarily increase. Since the duty

4

Test Circuit

VREF

VCC

VOUT

1kΩ

1W

0.1µF

VREF

VCC

VOUT

Gnd

VFB

Sense

OSC

COMP

5kΩ

100kΩ

4.7kΩ

1kΩ

ERROR AMP

ADJUST

4.7kΩ

Sense

ADJUST

RT

2N2222

CT

Gnd

A

CS-3842B

CS-3843B

Circuit Description

Typical Performance Characteristics:

Oscillator Duty Cycle vs RT

Oscillator Frequency vs CT

VCC

ON/OFF Command

to reset of IC

VON

16V

8.4V

VOFF

10V

7.6V

CS3842B CS3843B

<0.5mA

<15mA

VON VOFF

ICC

VCC

Figure 1: Typical Undervoltage Characteristics

.0005

.001

.002

.003

.005

.01

.02

.03

.04

800

900

CT (µF)

700

600

500

400

300

200

100

.05

RT =1.5kΩ

RT =680Ω

RT =10kΩ

100

200

700

1k

2k

5k

7k

10k

80

90

RT (Ω)

70

60

50

40

30

20

10

4k

3k

500

400

300

100

Nº de peça semelhante - CS3843B

Fabricante Electrônico	Nome de Peças	Folha de dados	Descrição Electrónicos
ON Semiconductor	CS3843BGD14	68Kb / 8P	Off-Line Current Mode PWM Control Circuit December, 2001 - Rev. 4
	CS3843BGD8	68Kb / 8P	Off-Line Current Mode PWM Control Circuit December, 2001 - Rev. 4
	CS3843BGDR14	68Kb / 8P	Off-Line Current Mode PWM Control Circuit December, 2001 - Rev. 4
	CS3843BGDR8	68Kb / 8P	Off-Line Current Mode PWM Control Circuit December, 2001 - Rev. 4
	CS3843BGN8	68Kb / 8P	Off-Line Current Mode PWM Control Circuit December, 2001 - Rev. 4

More results

Descrição semelhante - CS3843B

Fabricante Electrônico	Nome de Peças	Folha de dados	Descrição Electrónicos
ON Semiconductor	CS3842B	68Kb / 8P	Off-Line Current Mode PWM Control Circuit December, 2001 - Rev. 4
ON Semiconductor	CS2842A	273Kb / 10P	Off-Line Current Mode PWM Control Circuit with Undervoltage Lockout July, 2006 ??Rev. 4
Cherry Semiconductor Co...	CS2842A	156Kb / 6P	Off-Line Current Mode PWM Control Circuit with Undervoltage Lockout
Cherry Semiconductor Co...	CS52843	147Kb / 6P	Current Mode PWM Control Circuit
ON Semiconductor	CS52843	240Kb / 9P	Current Mode PWM Control Circuit July, 2006 ??Rev. 4
	CS3845B	63Kb / 8P	Current Mode PWM Control Circuit December, 2001 - Rev. 7
	CS2844	162Kb / 12P	Current Mode PWM Control Circuit June, 2001 ??Rev. 3
	CS2841B	100Kb / 10P	Automotive Current Mode PWM Control Circuit September, 2005 ??Rev. 7
Cherry Semiconductor Co...	CS2841B	162Kb / 6P	Automotive Current Mode PWM Control Circuit
ON Semiconductor	NCP1251	275Kb / 24P	Current-Mode PWM Controller for Off-line Power Supplies October, 2011 ??Rev. 7

More results

CS3843B Folha de dados(PDF) 4 Page - Cherry Semiconductor Corporation

CS3843B Folha de dados(HTML) 4 Page - Cherry Semiconductor Corporation

Nº de peça semelhante - CS3843B

Descrição semelhante - CS3843B

Html Pages

1 2 3 4 5 6

Folha de dados Download

Ligação URL