- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄377766 > LTC1980EGN (LINEAR TECHNOLOGY CORP) Combination Battery Charger and DC/DC Converter PDF資料下載
LTC1980
10
1980i
Lithium-Ion Battery Charger Operation
With the wall adapter power applied, the LTC1980 oper-
ates as a constant-current/constant-voltage PWM battery
charger, with a portion of the adapter current used for
charging and the rest flowing to the system load through
an optional low dropout regulator.
A charge cycle begins when the voltage at V
REG
exceeds
the undervoltage lockout threshold level and the IC is
enabled via the MODE pin. If the battery has been deeply
discharged and the battery voltage is less than 2.7V, the
charger will begin with the programmed trickle charge
current.
When the battery exceeds 2.7V, the charger begins the
constant-current portion of the charge cycle with the
charge current equal to the programmed level. As the
battery accepts charge, the voltage increases. When the
battery voltage reaches 3.8V, the programmable timer
begins. Constant-current charging continues until the
battery approaches the programmed charge voltage of
4.1V or 4.2V/cell at which time the charge current will
begin to drop, signaling the beginning of the constant-
voltage portion of the charge cycle. The charger will
maintain the programmed preset float voltage across the
battery until the timer terminates the charge cycle. During
trickle charging, if the battery voltage remains below 2.7V
for 1/4 of the total programmed charge time, the battery
may be defective and the charge cycle ends. Also, if a
battery open circuit is detected, the charge cycle ends
immediately. The charger can be shut down by pulling the
REG pin low, although the timer will continue until it times
out.
Power Converter Operation from Battery
When the AC adapter is removed, the LTC1980 operates as
a DC/DC PWM converter using the battery for input power
to provide a regulated output voltage for the system load.
The LTC1980 is a current mode switcher. This means that
the switch duty cycle is directly controlled by switch
current rather than by output voltage or current. Battery
charger operation will be described for the simplified
diagram (Figure 3). At the start of the oscillator cycle, latch
U9 is set causing M2 to turn on. When switch current
reaches a predetermined level M2 turns off and M1 turns
on. This level is set by the control voltage at the output of
error amplifier U10.
OPERATIOU
U4
DRIVERS
BDRIVE
–
+
–
+
–
+
–
+
–
+
–
+
–
+
T1
U1 VOLTAGE
SELECTION
B1
C1
+
RDRIVE
U11
REFERENCE
R1
R7
R2
R5
C2
R12
TO SYSTEM
LOAD
R13
R8
R9
U2
V
REF
V
REF
U5
U6
U8
U10
DIRECTION
TYPICAL
WAVEFORM
CURRENT
AMPLIFIER
SENSE
ZC
SW1
SW3
SW2
EA
C5
U7
OSC
R6
C3
C4
PWM
WALL
ADAPTER
S
R
Q
U9
1980 F03
M1 M2
R4
SN1 SNUBBER
NETWORK
SN2 SNUBBER
NETWORK
–
+
U12
V
REF
R10
R11
C6
V
BAT
V
REG
Figure 3. Simplified Diagram—Power Converter
相關PDF資料 |
PDF描述 |
|---|---|
| LTC1982ES6 | Single and Dual Micropower High Side Switch Controllers in SOT-23 |
| LTC1981 | Single and Dual Micropower High Side Switch Controllers in SOT-23 |
| LTC1981ES5 | Single and Dual Micropower High Side Switch Controllers in SOT-23 |
| LTC1982 | Single and Dual Micropower High Side Switch Controllers in SOT-23 |
| LTC1983-3 | 100mA REGULATED CHARGE-PUMP INVERTERS IN THINSOT |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| LTC1980EGN#PBF | 功能描述:IC PWM BATT CHARGER/CONV 24-SSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 電池管理 系列:- 產品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 功能:電池監(jiān)控器 電池化學:堿性，鋰離子，鎳鎘，鎳金屬氫化物 電源電壓:1 V ~ 5.5 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:SOT-23-6 供應商設備封裝:SOT-6 包裝:帶卷 (TR) |
| LTC1980EGN#TR | 功能描述:IC PWM BATT CHARGER/CONV 24-SSOP RoHS:否 類別:集成電路 (IC) >> PMIC - 電池管理 系列:- 產品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 功能:電池監(jiān)控器 電池化學:堿性，鋰離子，鎳鎘，鎳金屬氫化物 電源電壓:1 V ~ 5.5 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:SOT-23-6 供應商設備封裝:SOT-6 包裝:帶卷 (TR) |
| LTC1980EGN#TRPBF | 功能描述:IC PWM BATT CHARGER/CONV 24-SSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 電池管理 系列:- 產品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 功能:電池監(jiān)控器 電池化學:堿性，鋰離子，鎳鎘，鎳金屬氫化物 電源電壓:1 V ~ 5.5 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:SOT-23-6 供應商設備封裝:SOT-6 包裝:帶卷 (TR) |
| LTC1981ES5 | 制造商:Linear Technology 功能描述:MOSFET DRVR 1-OUT Hi Side 5-Pin TSOT-23 |
| LTC1981ES5#PBF | 制造商:Linear Technology 功能描述:MOSFET DRVR 1-OUT Hi Side 5-Pin TSOT-23 制造商:Linear Technology 功能描述:DP-Power Controller, CUT TAPE Single Micropower Hi Side Sw Controller 制造商:Linear Technology 功能描述:DRIVER, MOSFET, HIGH/LOW SIDE, SOT-23, Device Type:MOSFET, Module Configuration:High Side, Low Side, Supply Voltage Min:1.8V, Supply Voltage Max:5.5V, Driver Case Style:SOT-23, No. of Pins:5, Operating Temperature Min:-40C , RoHS Compliant: Yes |
發(fā)布緊急采購，3分鐘左右您將得到回復。