- 您現(xiàn)在的位置：買賣IC網 > PDF目錄382306 > MC44604 (ON SEMICONDUCTOR) High Safety Pulsed Mode Stanby GreenLine PWM Controller PDF資料下載
參數(shù)資料
| 型號： | MC44604 |
| 廠商： | ON SEMICONDUCTOR |
| 英文描述： | High Safety Pulsed Mode Stanby GreenLine PWM Controller |
| 中文描述： | 高安全性脈沖模式Stanby二七二三六七六七PWM控制器 |
| 文件頁數(shù)： | 14/24頁 |
| 文件大小： | 341K |
| 代理商： | MC44604 |
MC44604
http://onsemi.com
14
Error Amplifier
A fully compensated Error Amplifier with access to the
inverting input and output is provided. It features a typical
DC voltage gain of 70 dB. The non–inverting input is
internally biased at 2.5 V and is not pinned out. The
converter output voltage is typically divided down and
monitored by the inverting input. The maximum input bias
current with the inverting input at 2.5 V is –2.0
μ
A. This can
cause an output voltage error that is equal to the product of
the input bias current and the equivalent input divider source
resistance.
The Error Amp Output (Pin 13) is provided for external
loop compensation. The output voltage is offset by two
diodes drops (
1.4 V) and divided by three before it
connects to the inverting input of the Current Sense
Comparator. This guarantees that no drive pulses appear at
the Source Output (Pin 3) when Pin 13 is at its lowest state
(VOL). This occurs when the power supply is operating and
the load is removed, or at the beginning of a soft–start
interval. The Error Amp minimum feedback resistance is
limited by the amplifier’s minimum source current (0.2 mA)
and the required output voltage (VOH) to reach the current
sense comparator’s 1.0 V clamp level:
Rf(min)
3·0(1·0 V)
1·4 V
0·2 mA
22 k
+
1.0 mA
2.5 V
Figure 28. Error Amplifier Compensation
Compensation
RFB
C1
R1
R2
Rf
13
14
Voltage
Feedback
Input
Error
Amplifier
2R
R
1.0 V
Current
Sense
Comparator
Gnd
4
MC44604
4.7 W
+
5
Foldback
Input
Pin 12
In a preferred embodiment, the feedback signal (current)
is drawn from the pin 12 that is connected to the pin 15 in
normal mode (Note 1). Using a resistor connected on pin 12,
this current generates a voltage that is the input signal of the
error amplifier arrangement.
Note 1. The error amplifier is not used in the standby mode
regulation.
Current Sense Comparator and PWM Latch
The MC44604 can operate as a current mode controller
and/or as a voltage mode controller. In current mode
operation, the MC44604 uses the current sense comparator,
where the output switch conduction is initiated by the
oscillator and terminated when the peak inductor current
reaches the threshold level established by the Error
Amplifier output (Pin 13). Thus the error signal controls the
peak inductor current on a cycle–by–cycle basis. The
Current Sense Comparator PWM Latch configuration used
ensures that only a single pulse appears at the Source Output
during the appropriate oscillator cycle.
The inductor current is converted to a voltage by inserting
the ground referenced sense resistor RS in series with the
power switch Q1.
In normal mode, this voltage is monitored by the Current
Sense Input (Pin 7) and compared to a level derived from the
Error Amp output. The peak inductor current under normal
operating conditions is controlled by the voltage at Pin 13
where:
Ipk
V(pin13)
1·4 V
3 RS
The Current Sense Comparator threshold is internally
clamped to 1.0 V. Therefore the maximum peak switch
current is:
Ipk(max)
1·0 V
RS
Figure 29. Output Totem Pole
R
S
Q
UVLO
VOSCPROT
Vdemag out
Thermal
Protection
PWM
Latch
Current Sense
Comparator
Substrate
Current
Sense
14
3
7
C
RS
R
R3
Q1
Vin
VC
R2
VOSC
(from Oscillator)
R
Oscillator
The oscillator is a very accurate sawtooth generator.
相關PDF資料 |
PDF描述 |
|---|---|
| MC44604P | RV Series - Econoline Unregulated DC-DC Converters; Input Voltage (Vdc): 3.3V; Output Voltage (Vdc): 3.3V; Power: 2W; High Isolation 2W Converter; Approved for Medical Applications; EN and UL Safety Certificates; 6kVDC Isolation; Skinny DIP24 Package; Optional Continuous Short Circuit Protected; Fully Encapsulated; Very Low Isolation Capacitance |
| MC44605 | High Safety, Latched Mode, GreenLine PWM Controller for (Multi)Synchronized Applications |
| MC44605P | RW-S Series - Econoline Regulated DC-DC Converters; Input Voltage (Vdc): 05V; Output Voltage (Vdc): 05V; Power: 2W; DIP24 Low Profile Miniature Package; 1kVDC Isolation; Feedback Regulated Output; 2:1 Wide Range Voltage Input; Continuous Short Circuit Protection; Less than 7mm Height; SMD Pinning Option; Efficiency to 87% |
| MC44608P75 | Few External Components Reliable Flexible GreenLine Very High Voltage PWM Controller |
| MC44608 | Few External Components Reliable Flexible GreenLine Very High Voltage PWM Controller |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| MC44604_05 | 制造商:ONSEMI 制造商全稱:ON Semiconductor 功能描述:High Safety Pulsed Mode Standby GreenLine TM PWM Controller |
| MC44604P | 功能描述:電流型 PWM 控制器 Voltage Mode PWM RoHS:否 制造商:Texas Instruments 開關頻率:27 KHz 上升時間: 下降時間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風格:SMD/SMT 封裝 / 箱體:TSSOP-14 |
| MC44604PG | 功能描述:電流型 PWM 控制器 Voltage Mode PWM w/Bust Mode Standby RoHS:否 制造商:Texas Instruments 開關頻率:27 KHz 上升時間: 下降時間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風格:SMD/SMT 封裝 / 箱體:TSSOP-14 |
| MC44605 | 制造商:ONSEMI 制造商全稱:ON Semiconductor 功能描述:High Safety, Latched Mode, GreenLine PWM Controller for (Multi)Synchronized Applications |
| MC44605_06 | 制造商:ONSEMI 制造商全稱:ON Semiconductor 功能描述:High Safety, Latched Mode, GreenLine TM PWM Controller for (Multi) Synchronized Applications |
發(fā)布緊急采購，3分鐘左右您將得到回復。