- 您現在的位置：買賣IC網 > PDF目錄98283 > TPS56121DQPT (TEXAS INSTRUMENTS INC) SWITCHING CONTROLLER, 1100 kHz SWITCHING FREQ-MAX, PDSO22 PDF資料下載
參數資料
| 型號： | TPS56121DQPT |
| 廠商： | TEXAS INSTRUMENTS INC |
| 元件分類： | 穩壓器 |
| 英文描述： | SWITCHING CONTROLLER, 1100 kHz SWITCHING FREQ-MAX, PDSO22 |
| 封裝： | ROHS COMPLIANT, PLASTIC, SON-22 |
| 文件頁數： | 3/25頁 |
| 文件大小： | 653K |
| 代理商： | TPS56121DQPT |
=
÷
è
SS
FB
I
C
t
V
(
)
-
=
-
+
÷
÷
è
è
P P
OCSET
OUT max
I
R
I
95
500
2
SLUSAH4
– MARCH 2011
time once calibration is complete. The discharging current is from an internal current source of 140
μA and it
pulls the voltage down to 0.4 V. It then initiates the soft-start by charging up the capacitor using an internal
current source of 10
μA. The resulting voltage ramp on this pin is used as a second non-inverting input to the
error amplifier after an 800 mV (typical) downward level-shift; therefore, the actual soft-start does not take place
until the voltage at this pin reaches 800 mV.
If the EN/SS pin is left floating, the controller starts automatically. EN/SS must be pulled down to less than 270
mV to ensure that the chip is in shutdown mode.
Soft-Start Time
The soft-start time of the TPS56121 is user programmable by selecting a single capacitor. The EN/SS pin
sources 10
μA to charge this capacitor. The actual output ramp-up time is the amount of time that it takes for the
10
μA to charge the capacitor through a 600 mV range. There is some initial lag due to calibration and an offset
(800 mV) from the actual EN/SS pin voltage to the voltage applied to the error amplifier.
The soft-start is accomplished in a closed-loop, meaning that the error amplifier controls the output voltage at all
times during the soft-start period and the feedback loop is never open as occurs in duty cycle limit soft-start
schemes. The error amplifier has two non-inverting inputs, one connected to the 600-mV reference voltage, and
the other connected to the offset EN/SS pin voltage. The lower of these two voltages is what the error amplifier
controls the FB pin to. As the voltage on the EN/SS pin ramps up past approximately 1.4 V (800 mV offset
voltage plus the 600 mV reference voltage), the 600-mV reference voltage becomes the dominant input and the
converter has reached its final regulation voltage.
The capacitance required for a given soft-start ramp time for the output voltage is calculated in Equation 1.
where
CSS is the required capacitance on the EN/SS pin (nF)
ISS is the soft-start source current (10 μA)
VFB is the feedback reference voltage (0.6 V)
tSS is the desired soft-start ramp time (ms)
(1)
Oscillator
The oscillator frequency is internally fixed at 500 KHz if there is no resistor connected from COMP pin to GND.
Optionally, a 40.2-k
Ω resistor from the COMP pin to GND sets the frequency to 300 KHz. Alternatively, a 13.3-kΩ
resistor from COMP pin GND sets the frequency to 1 MHz.
Overcurrent Protection (OCP)
Programmable OCP level at ILIM is from 6 mV to 50 mV. With a scale factor of 2, the actual OC trip point across
the low-side FET is in the range of 12 mV to 100 mV.
If the voltage drop across ROCSET reaches 300 mV during calibration (No ROCSET resistor included), it disables
OC protection. Once disabled, there is no low-side or high-side current sensing.
OCP level for the high-side FET is fixed at 34 A (typical). The high-side OCP provides pulse-by-pulse current
limiting.
OCP sensing for the low-side FET is a true inductor valley current detection, using sample and hold. Equation 2
can be used to calculate ROCSET.
where
IP-P is the peak-to-peak inductor current (A)
IOUT(max) is the trip point for OCP (A)
ROC(set) is the resistor used for setting the OCP level ()
(2)
Copyright
2011, Texas Instruments Incorporated
11
Product Folder Link(s) :TPS56121
相關PDF資料 |
PDF描述 |
|---|---|
| TPS5615CPWP | SWITCHING CONTROLLER, PDSO28 |
| TPS5625CPWPR | SWITCHING CONTROLLER, PDSO28 |
| TPS56221DQPR | SWITCHING CONTROLLER, PDSO22 |
| TPS57040QDGQRQ1 | SWITCHING REGULATOR, 2500 kHz SWITCHING FREQ-MAX, PDSO10 |
| TPS57114QRTERQ1 | SWITCHING REGULATOR, 2000 kHz SWITCHING FREQ-MAX, PQCC16 |
相關代理商/技術參數 |
參數描述 |
|---|---|
| TPS56121DQPT | 制造商:Texas Instruments 功能描述:IC SYNC BUCK CONV 14 VIN 12 VOUT 15A |
| TPS56121EVM-601 | 功能描述:電源管理IC開發工具 TPS56121 Eval Mod RoHS:否 制造商:Maxim Integrated 產品:Evaluation Kits 類型:Battery Management 工具用于評估:MAX17710GB 輸入電壓: 輸出電壓:1.8 V |
| TPS5615EVM-114 | 功能描述:HIGH-PERFORMANCE SYNCHRONOUS BUC RoHS:是 類別:編程器，開發系統 >> 評估板 - DC/DC 與 AC/DC（離線）SMPS 系列:- 產品培訓模塊:Obsolescence Mitigation Program 標準包裝:1 系列:True Shutdown™ 主要目的:DC/DC，步升 輸出及類型:1，非隔離 功率 - 輸出:- 輸出電壓:- 電流 - 輸出:1A 輸入電壓:2.5 V ~ 5.5 V 穩壓器拓撲結構:升壓 頻率 - 開關:3MHz 板類型:完全填充 已供物品:板 已用 IC / 零件:MAX8969 |
| TPS5615EVM-115 | 功能描述:HIGH-PERFORMANCE SYNCHRONOUS BUC RoHS:是 類別:編程器，開發系統 >> 評估板 - DC/DC 與 AC/DC（離線）SMPS 系列:- 產品培訓模塊:Obsolescence Mitigation Program 標準包裝:1 系列:True Shutdown™ 主要目的:DC/DC，步升 輸出及類型:1，非隔離 功率 - 輸出:- 輸出電壓:- 電流 - 輸出:1A 輸入電壓:2.5 V ~ 5.5 V 穩壓器拓撲結構:升壓 頻率 - 開關:3MHz 板類型:完全填充 已供物品:板 已用 IC / 零件:MAX8969 |
| TPS5615PWP | 功能描述:IC BUCK REG CNTRLR 28-HTSSOP RoHS:否 類別:集成電路 (IC) >> PMIC - 穩壓器 - 專用型 系列:- 標準包裝:2,000 系列:- 應用:控制器，DSP 輸入電壓:4.5 V ~ 25 V 輸出數:2 輸出電壓:最低可調至 1.2V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:30-TFSOP（0.173"，4.40mm 寬） 供應商設備封裝:30-TSSOP 包裝:帶卷 (TR) |
發布緊急采購，3分鐘左右您將得到回復。