AD7877 触摸屏控制器_WOSENDONGLI代理AD7877

AD7877: 触摸屏控制器

AD7877是一款12位逐次逼近型ADC,具有同步串行接口以及用于驱动触摸屏的低导通电阻开关,采用2.7 V至5.25 V单电源供电（2.2 V也可正常运转）,吞吐量为125 kSPS。AD7877可用于两个输入上的电池测量、温度测量和触摸压力测量。AD7877还具有一个2.5 V片上基准电压源。不使用时,可关断基准电压源以降低功耗。也可以使用外部基准电压,并可在1 V至+VCC范围内变化,模拟输入范围为0 V至VREF。这款器件具有关断模式,此模式下功耗不足1 uA。片上ADC的相位采集通过STOPACQ引脚来控制,这样可以降低来自LCD的噪声影响。用户可编程转换控制包括可变采集时间及第一转换延迟。每次转换可利用多达16个均值。该器件还有一个片上DAC,用来控制LCD背光或对比度。AD7877采用转换序列器与定时器,可在从模式或主模式下工作,非常适用于电池供电系统,如带电阻触摸屏的个人数字助理及其它便携式设备。该器件提供两种封装：32引脚架构芯片级封装（LFCSP）和25引脚晶圆级芯片规模封装（WLCSP）。

AD7877 功能框图 The AD7877 is a 12-bit, successive approximation ADC with a synchronous serial interface and low on resistance switches for driving touch screens. The AD7877 operates from a single 2.7 V to 5.25 V power supply (functional operation to 2.2 V), and features throughput rates of 125 kSPS. The AD7877 features direct battery measurement on two inputs, temperature and touch-pressure measurement.The AD7877 also has an on-board reference of 2.5 V. When not in use, it can be shut down to conserve power. An external reference can also be applied and varied from 1 V to +VCC, with an analog input range of 0 V to VREF. The device includes a shutdown mode that reduces its current consumption to less than 1 uA.To reduce the effects of noise from LCDs, the acquisition phase of the on-board ADC is controlled via the STOPACQ pin. User-programmable conversion controls include variable acquisition time and first conversion delay. Up to 16 averages can be taken per conversion. There is also an on-board DAC for LCD back-light or contrast control. The AD7877 runs in either slave or master mode using a conversion sequencer and timer. It is ideal for battery-powered systems such as personal digital assistants with resistive touch screens and other portable equipment.The part is available in a 32-lead lead frame chip scale package (LFCSP), and a 25-ball wafer level chip scale package (WLCSP).

AD7877 特性

4线触摸屏接口
LCD降噪特性（STOPACQ引脚）
自动转换序列器与定时器
用户可编程的转换参数
片内温度传感器：-40°C至+85°C
2.5 V片内基准电压源
片内8位DAC
3个辅助模拟输入
1个专用GPIO和3个可选GPIO
2个电池测量通道（0.5 V至5 V）
3个中断输出
触摸压力测量

AD7877 技术指标

Resolution (Bits): 12bit
# Chan: 9
Sample Rate: 125kSPS
Interface: Ser
Analog Input Type: SE-Uni
Ain Range: Uni (Vref),Uni 2.5V
ADC Architecture: SAR
Pkg Type: CSP

AD7877 应用领域

个人数字助理
智能手持式设备
触摸屏监控器
POS终端机
医疗设备
蜂窝电话
寻呼机

AD7877 芯片订购指南

产品型号	封装	引脚	温度范围	包装和数量	报价*(100-499)	报价*1000 pcs
AD7877ACBZ-REEL 产品状态: 量产	25 Ball WLCSP	25	工业	Reel, 10000	$ 2.20	$ 2.15
AD7877ACBZ-REEL7 产品状态: 量产	25 Ball WLCSP	25	工业	Reel, 3000	-	$ 2.15
AD7877ACPZ-500RL7 产品状态: 量产	32 ld LFCSP (5x5mm CP-32-2)	32	工业	Reel, 500	-	$ 2.15
AD7877ACPZ-REEL 产品状态: 量产	32 ld LFCSP (5x5mm CP-32-2)	32	工业	Reel, 5000	-	$ 2.15
AD7877ACPZ-REEL7 产品状态: 量产	32 ld LFCSP (5x5mm CP-32-2)	32	工业	Reel, 1500	-	$ 2.15
AD7877WACPZ-REEL7 产品状态: 量产	32 ld LFCSP (5x5mm CP-32-2)	32	工业	Reel, 1500	-	$ 2.30