LMP91000 RE CE WE 的电位

各位TI专家好，我在用LMP91000作为电化学测试，然后发现空载时，测WE与CE之间有一个电压值，大小为50%VREF，然后参比电极和工作电极之间电压为0.

但我设置的不是参比电极和对电极之间的偏压为一定的值吗？

为什么是这种情况，我这种情况是正确的吗？代码如下：

#define TI_LMP91000_TIACN_REG_VALUE (0x1F) /* default r=14k*/
#define TI_LMP91000_REFCN_REG_VALUE (0x28) /* default */
#define TI_LMP91000_MODECN_REG_VALUE (0x03) /* default */

uint8_t read_val[2];
uint8_t status = TI_LMP91000_NOT_READY;

//WDTCTL = WDTPW + WDTHOLD; // Stop watchdog timer

//TI_LMP91000_LED_PxOUT |= TI_LMP91000_LED_PIN; // Set LED ON//自己根据实际情况更改，串口输入输出
//TI_LMP91000_LED_PxDIR |= TI_LMP91000_LED_PIN; // Set pin direction is output

I2CSetup(LMP91000_I2C_Address); // Initialize I2C module

//TI_LMP91000_MENB_PxOUT &= ~TI_LMP91000_MENB_PIN; // Enable \MENB Pin，同上
//TI_LMP91000_MENB_PxDIR |= TI_LMP91000_MENB_PIN; // Set pin direction is output

while (status == TI_LMP91000_NOT_READY)
status = LMP91000_I2CReadReg(TI_LMP91000_STATUS_REG); // Read device ready status

LMP91000_I2CWriteReg(TI_LMP91000_LOCK_REG, TI_LMP91000_WRITE_UNLOCK); // unlock the registers for write

LMP91000_I2CWriteReg(TI_LMP91000_TIACN_REG, TI_LMP91000_TIACN_REG_VALUE); // Modify TIA control register
LMP91000_I2CWriteReg(TI_LMP91000_REFCN_REG, TI_LMP91000_REFCN_REG_VALUE); // Modify REF control register

read_val[0] = LMP91000_I2CReadReg(TI_LMP91000_TIACN_REG); // Read to confirm register is modified
read_val[1] = LMP91000_I2CReadReg(TI_LMP91000_REFCN_REG); // Read to confirm register is modified

if ((read_val[0] != TI_LMP91000_TIACN_REG_VALUE) ||
(read_val[1] != TI_LMP91000_REFCN_REG_VALUE)) // test values took effect
while (1); // otherwise error

// lock the registers
LMP91000_I2CWriteReg(TI_LMP91000_MODECN_REG, TI_LMP91000_MODECN_REG_VALUE); // 3-lead amperometric cell
LMP91000_I2CWriteReg(TI_LMP91000_LOCK_REG, TI_LMP91000_WRITE_LOCK);