參數(shù)資料
型號(hào): LP3906SQDJXI
廠商: NATIONAL SEMICONDUCTOR CORP
元件分類: 穩(wěn)壓器
英文描述: 2 A DUAL SWITCHING CONTROLLER, 2000 kHz SWITCHING FREQ-MAX, QCC24
封裝: 5 X 4 MM, 0.80 MM HEIGHT, LLP-24
文件頁數(shù): 30/40頁
文件大?。?/td> 4197K
代理商: LP3906SQDJXI
High Vin-High Load Operation
Additional information is provided when the IC is operated at
extremes of Vin and regulator loads. These are described in
terms of the Junction temperature and, Buck output ripple
management.
Junction Temperature
The maximum junction temperature TJ-MAX-OP of 125C of
the IC package.
The following equations demonstrate junction temperature
determination, ambient temperature TA-MAX and Total chip
power must be controlled to keep TJ below this maximum:
TJ-MAX-OP
= TA-MAX + (
θJA) [ °C/ Watt] * (PD-MAX)
[Watts]
Total IC power dissipation PD-MAX is the sum of the individ-
ual power dissipation of the four regulators plus a minor
amount for chip overhead. Chip overhead is Bias, TSD & LDO
analog.
PD-MAX
= P
LDO1 + PLD02 + PBUCK1 + PBUCK2 + (0.0001A * Vin)
[Watts].
Power dissipation of LDO1
P
LDO1 = (VinLDO1- VoutLDO1) * IoutLDO1 [V*A]
Power dissipation of LDO2
P
LDO2 = (VinLDO2 - VoutLDO2) * IoutLDO2 [V*A]
Power dissipation of Buck1
P
Buck1 = PIN – POUT =
Vout
Buck1* IoutBuck1 * (1 -η
1) / η1 [V*A]
η1 = efficiency of buck 1
Power dissipation of Buck2
P
Buck2 = PIN – POUT =
Vout
Buck2 * IoutBuck2 * (1 - η
2) / η2 [V*A]
η2 = efficiency of buck 2
η is the efficiency for the specific condition taken from effi-
ciency graphs.
Buck Output Ripple Management
If Vin and ILoad increase, the output ripple associated with
the Buck Regulators also increases. The figure below shows
the safe operating area. To ensure operation in the area of
concern it is recommended that the system designer circum-
vents the output ripple issues to install schottky diodes on the
Bucks(s) that are expected to perform under these extreme
corner conditions.
(Schottky diodes are recommended to reduce the output rip-
ple if the system requirements include this shaded area of
operation. Vin > 5.2 V and Iload > 1.24 A)
LP3906 Buck Converter
V
IN vs ILOAD Operating Ranges
20197864
www.national.com
36
LP3906
相關(guān)PDF資料
PDF描述
LP3906SQXJXXI 2 A DUAL SWITCHING CONTROLLER, 2000 kHz SWITCHING FREQ-MAX, QCC24
LP3906SQXVPFP 2 A DUAL SWITCHING CONTROLLER, 2000 kHz SWITCHING FREQ-MAX, QCC24
LP3906SQXPPXP 2 A DUAL SWITCHING CONTROLLER, 2000 kHz SWITCHING FREQ-MAX, QCC24
LP3907SQ-JIXI 1.5 A DUAL SWITCHING CONTROLLER, 2100 kHz SWITCHING FREQ-MAX, QCC24
LP3918TL-I 1-CHANNEL POWER SUPPLY SUPPORT CKT, PBGA25
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LP3906SQ-DJXI 制造商:Texas Instruments 功能描述:Power Management Unit 24-Pin LLP EP T/R
LP3906SQ-DJXI/NOPB 功能描述:其他電源管理 RoHS:否 制造商:Texas Instruments 輸出電壓范圍: 輸出電流:4 mA 輸入電壓范圍:3 V to 3.6 V 輸入電流: 功率耗散: 工作溫度范圍:- 40 C to + 110 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-48 封裝:Reel
LP3906SQE-PPXP/NOPB 功能描述:其他電源管理 RoHS:否 制造商:Texas Instruments 輸出電壓范圍: 輸出電流:4 mA 輸入電壓范圍:3 V to 3.6 V 輸入電流: 功率耗散: 工作溫度范圍:- 40 C to + 110 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-48 封裝:Reel
LP3906SQE-VPFP/NOPB 功能描述:其他電源管理 RoHS:否 制造商:Texas Instruments 輸出電壓范圍: 輸出電流:4 mA 輸入電壓范圍:3 V to 3.6 V 輸入電流: 功率耗散: 工作溫度范圍:- 40 C to + 110 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-48 封裝:Reel
LP3906SQ-FXPI/NOPB 功能描述:其他電源管理 RoHS:否 制造商:Texas Instruments 輸出電壓范圍: 輸出電流:4 mA 輸入電壓范圍:3 V to 3.6 V 輸入電流: 功率耗散: 工作溫度范圍:- 40 C to + 110 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-48 封裝:Reel