- 您现在的位置：买卖IC网 > PDF目录383329 > MAX1644 (Maxim Integrated Products, Inc.) Advanced Chemistry-Independent, Level 2 Battery Charger with Input Current Limiting PDF资料下载
参数资料
| 型号： | MAX1644 |
| 厂商： | Maxim Integrated Products, Inc. |
| 英文描述： | Advanced Chemistry-Independent, Level 2 Battery Charger with Input Current Limiting |
| 中文描述： | 2A、低电压、降压型稳压器，内置同步整流与开关 |
| 文件页数： | 14/32页 |
| 文件大小： | 183K |
| 代理商： | MAX1644 |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页当前第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页
M
Advanc ed Chemistry-Independent, Level 2
Battery Charger with Input Current Limiting
14
______________________________________________________________________________________
Operating Conditions
The MAX1645 changes its operation depending on the
voltages at DCIN, BATT, V
DD,
and THM. Several impor-
tant operating states follow:
AC Present.
When DCIN is > 7.5V, the battery is
considered to be in an AC Present state. In this con-
dition, both the LDO and REF will function properly
and battery charging is allowed. When AC is pre-
sent, the AC _PRESENT bit (bit 15) in the
ChargerStatus() register is set to “1.”
Power Fail.
When DCIN is < BATT + 0.3V, the
MAX1645 is in the Power Fail state, since the charger
doesn’t have enough input voltage to charge the bat-
tery. In Power Fail, the PDS input PMOS switch is
turned off and the POWER_FAIL bit (bit 13) in the
ChargerStatus() register is set to “1.”
Battery Present.
When THM is < 91% of V
DD
, the
battery is considered to be present. The MAX1645
uses the THM pin to detect when a battery is con-
nected to the charger. When the battery is present,
the BATTERY_PRESENT bit (bit 14) in the
ChargerStatus() register is set to “1” and charging
can proceed. When the battery is not present, all of
the MAX1645 registers are reset. With no battery pre-
sent, the charger will still try to regulate the BATT pin
voltage at 18.432V with 128mA of current compliance.
Battery Undervoltage.
When BATT < 2.5V, the bat-
tery is in an undervoltage state. This causes the
charger to reduce its current compliance to 128mA.
The content of the ChargingCurrent() register is unaf-
fected and, when the BATT voltage exceeds 2.7V,
normal charging resumes. ChargingVoltage() is unaf-
fected and can be set as low as 1.024V.
V
DD
Undervoltage.
When V
DD
< 2.5V, the V
DD
sup-
ply is in an undervoltage state, and the SMBus inter-
face will not respond to commands. Coming out of
the undervoltage condition, MAX1645 will be in its
Power-On Reset state. No charging will occur when
V
DD
is under voltage.
S MBus Interfac e
The MAX1645 receives control inputs from the SMBus
interface. The serial interface complies with the SMBus
specification (refer to the System Management Bus
Specification from Intel Corporation). Charger function-
ality complies with the Intel/Duracell Smart Charger
Specification for a Level 2 charger.
The MAX1645 uses the SMBus Read-Word and Write-
Word protocols to communicate with the battery being
charged, as well as with any host system that monitors
the battery-to-charger communications as a Level 2
SMBus charger. The MAX1645 is an SMBus slave
device and does not initiate communication on the bus.
It receives commands and responds to queries for sta-
tus information. Figure 3 shows examples of the SMBus
Write-Word and Read-Word protocols, and Figures 4
and 5 show the SMBus serial-interface timing.
Each communication with the MAX1645 begins with the
MASTER issuing a START condition that is defined as a
falling edge on SDA with SCL high and ends with a
STOP condition defined as a rising edge on SDA with
SCL high. Between the START and STOP conditions,
the device address, the command byte, and the data
bytes are sent. The MAX1645 device address is 0x12
and supports the charger commands as described in
Tables 1–6.
Battery Charger Commands
ChargerSpecInfo()
The ChargerSpecInfo() command uses the Read-Word
protocol (Figure 3b). The command code for
ChargerSpecInfo() is 0x11 (0b00010001). Table 1 lists
the functions of the data bits (D0–D15). Bit 0 refers to
the D0 bit in the Read-Word protocol. The MAX1645 is
version 1.0; therefore, the ChargerSpecInfo() command
returns 0x01.
ChargerMode()
The ChargerMode() command uses the Write-Word
protocol (Figure 3a). The command code for
ChargerMode() is 0x12 (0b00010010). Table 2 lists the
functions of the data bits (D0–D15). Bit 0 refers to the
D0 bit in the Write-Word protocol.
To charge a battery that has a thermistor impedance in
the HOT range (i.e., THERMISTOR_HOT = 1 and THER-
MISTOR_UR = 0), the host must use the Charger
Mode() command to clear HOT_STOP after the battery
is inserted. The HOT_STOP bit returns to its default
power-up condition (“1”) whenever the battery is
removed.
ChargerStatus()
The ChargerStatus() command uses the Read-Word
protocol (Figure 3b). The command code for Charger
Status() is 0x13 (0b00010011). Table 3 describes the
functions of the data bits (D0–D15). Bit 0 refers to the
D0 bit in the Read-Word protocol.
The ChargerStatus() command returns information
about thermistor impedance and the MAX1645’s inter-
nal state. The latched bits, THERMISTOR_HOT and
ALARM_INHIBITED, are cleared whenever BATTERY_
PRESENT = 0 or C hargerMode() is written with
POR_RESET = 1. The ALARM_INHIBITED status bit can
also be cleared by writing a new charging current OR
charging voltage.
相关PDF资料 |
PDF描述 |
|---|---|
| MAX1645B | Advanced Chemistry-Independent, Level 2 Battery Charger with Input Current Limiting |
| MAX1645BEEI | Advanced Chemistry-Independent, Level 2 Battery Charger with Input Current Limiting |
| MAX1647 | Chemistry-Independent Battery Chargers |
| MAX1648 | Chemistry-Independent Battery Chargers |
| MAX1647-MAX1648 | Chemistry-Independent Battery Chargers |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX1644EAE | 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| MAX1644EAE/GH9 | 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| MAX1644EAE/GH9-T | 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| MAX1644EAE+ | 功能描述:直流/直流开关转换器 2A Step-Dow w/Synch Rectification RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| MAX1644EAE+T | 功能描述:直流/直流开关转换器 2A Step-Dow w/Synch Rectification RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
发布紧急采购，3分钟左右您将得到回复。