板子不焊接CPU整板功耗40uA左右焊接CPU,进入LPM4后,整板功耗170uA左右,CPU功耗有130uA左右
LPM4模式下 CPU and all clocks are disabled ,官方数据手册该模式下只有0.4uA的功耗
数据手册有这样一句说明 Although the I/O register contents are lost, the I/O pin states are locked upon LPMx.5 entry
所以不排除IO口默认值引起一些功耗,但是单独针对某一可能的IO口尝试各种置位处理,功耗反而会升上去(1.4mA左右)........
求指点,怎么把CPU功耗降下去!!!
主要测试程序如下;
Sys_Init();
LED_ON();
__delay_cycles(800000); // Wait 8,000,000 CPU Cycles
LED_OFF();
LPM4;
//==============================
void Sys_Init ( void )
{
WDTCTL = WDTPW | WDTHOLD; // Stop WDT
// Configure GPIO
P1OUT &= ~BIT0; // Clear P1.0 output latch for a defined power-on state
P1DIR |= BIT0; // Set P1.0 to output direction
PJDIR |= BIT2;
PJSEL0 |= BIT2; // Output ACLK
PJSEL1 &= ~BIT2;
P7DIR |= BIT4;
P7SEL1 |= BIT4; // Output SMCLK
P7SEL0 |= BIT4;
// Disable the GPIO power-on default high-impedance mode to activate
// previously configured port settings
PM5CTL0 &= ~LOCKLPM5;
// Clock System Setup
CSCTL0_H = CSKEY >> 8; // Unlock CS registers
CSCTL1 = DCOFSEL_6; // Set DCO to 8MHz
CSCTL2 = SELA__VLOCLK | SELS__DCOCLK | SELM__DCOCLK; // Set SMCLK = MCLK = DCO
// ACLK = VLOCLK
CSCTL3 = DIVA__1 | DIVS__1 | DIVM__1; // Set all dividers to 1
CSCTL0_H = 0; // Lock CS registers
} |