參數(shù)資料
型號(hào): TPS40022PWPR
廠商: TEXAS INSTRUMENTS INC
元件分類: 穩(wěn)壓器
英文描述: 0.01 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDSO16
封裝: POWERPAD, PLASTIC, HTSSOP-16
文件頁(yè)數(shù): 11/29頁(yè)
文件大?。?/td> 337K
代理商: TPS40022PWPR
TPS40020
TPS40021
TPS40022
SLUS535 – MARCH 2003
www.ti.com
19
REFERENCE DESIGN
MOSFETs and Diodes
For a 1.5-V output voltage, the lower the RDS(on) of the MOSFET, the higher the efficiency. Due to the high
current and high conduction loss, the MOSFET should have very low conduction resistance (RDS(on)) and
thermal resistance. Si7858DP is chosen for its low RDS(on) (between 3 m and 4 m) and Power-Pak package.
Current Limiting
Resistor R3 sets the over current limit threshold. The RDS(on) of the upper MOSFET is used as a current sensor.
The current limit is initialized at 40% above the maximum output current, IOUT(max), which is 28 A. Then R3 can
be calculated in equation (11) and yields a value of 1.43 k
.
I
LIM +
20
V
REF
R4
+ 20
0.7 V
118 k
W +
118.6 (
mA)
R3
+
K
R
DS(on)
I
OUT
I
LIM
(
mA)
+
1.5
4(
mW)
28 A
I
LIM
(
mA)
+ 1.43 (kW)
where
D RDS(on) is the on-resistor of Q1 (4 m)
D Temperature coefficient, K=1.5
D VREF=0.7 V
D R4=118 k
Voltage Sense Regulator
R1 and R2 operate as the output voltage divider. The internal reference voltage (VREF) is 0.7 V. The relationship
between the output voltage and divider is described in equation (8). Using a 10-k
resistor for R2 and 1.5-V
output regulation, R1 is calculated as 8.66 k
.
V
REF
R1
+
V
OUT
R1
) R2
+ 0.7 V
R1
+
1.5 V
R1
) 10 kW
+ 8.66 kW
Transient Comparator
The output voltage transient comparators provide a quick response, first strike, approach to output voltage
transients. The output voltage is sensed through a resistor divider at the OSNS pin, using R5 and R6 shown
in Figure 6. If an overvoltage condition is detected, the HDRV gate drive is shut off and the LDRV gate drive
is turned on until the output is returned to regulation. Similarly, if an output undervoltage condition is sensed,
the HDRV gate drive goes to 95% duty cycle to pump the output back up quickly. The voltage divider should
keep same ratio as the output voltage sensor for the PWM comparator. Resistor R5=8.66 k
and R6=10 k
in this evaluation module.
(13)
(14)
(15)
相關(guān)PDF資料
PDF描述
TPS40042DRCTG4 SWITCHING CONTROLLER, 700 kHz SWITCHING FREQ-MAX, PDSO10
TPS40055MPWPREPG4 SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDSO16
TPS40055QPWPRQ1 SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDSO16
TPS40054QPWPRQ1 SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDSO16
TPS40070PWPRG4 2 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDSO16
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TPS40040 制造商:TI 制造商全稱:Texas Instruments 功能描述:LOW PIN COUNT, LOW VIN (2.5 V TO 5.5 V) SYNCHRONOUS BUCK DC-TO-DC CONTROLLER WITH ENABLE
TPS40040DRBR 功能描述:DC/DC 開關(guān)控制器 Lo Vin Synch Buck DC/DC Cntrlr RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
TPS40040DRBRG4 功能描述:DC/DC 開關(guān)控制器 Lo Vin Synch Buck DC/DC Cntrlr RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
TPS40040DRBT 功能描述:DC/DC 開關(guān)控制器 Low Vin Synch Buck DC/DC Controller RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
TPS40040DRBT 制造商:Texas Instruments 功能描述:Peak Reflow Compatible (260 C):Yes