IWR1443BOOST: current draw

Hello,
Depending on the software running on the radar-sensor, the power draw changes.
a) if you run the Out Of Box demonstration, while the mmwave sensor is booting from nRESET release to sending data over the UART.
during the boot process, the RF is relatively low power, the core digital and processor draw 1.2v power. The 1.8v digital, and 3.3v digital
have a small load. in this case .21A for radar, .07A for XDS110.

b) once the chirp/frame is running the power consumed is higher. We would have a higher current draw with more RF activity + .07A XDS110.

1) I think for the Out of Box demos, if you are getting the Visualizer display (I usually use a metal can or water bottle) if you power up the EVM, with the Out of Box Demo, it is waiting to be programmed. The .28A would be OK.

2) When you send the active chirp/frame selection, and send the target reflections back, we would expect the power drawn to increase to .75 to 1.5w given a 50% efficient power supply, we would draw 1.5 to 3w from the 5v input which is .3 to .6A.

If you develope a product, the power supply efficiency can be changed:
- standard ~50%, also includes XDS110 which draws .07A
- swra577 - modified EVM supply - 60% efficiency
- 3rd quarter release of TIDEP91 with reprogrammed and optimized supply - 70% efficiency

There are discrete DCDC converters which can provide more efficient power use, these do not fit within the EVM supply architecture, they require
a custom board.

Regards,
Joe QUintal

Hello,

Using a power supply and a current meter here are the values I get with an IWR1443 ES2 EVM, in reset, flashing, and running the High Accuracy demo

on the board R176 is the supply to the 3v3board for XDS110 and external temperature sensors.   You could put a jumper in place of R176, if you want the mmwave sensor only, but in that case, the USB to Control UART and MSS Logger UART would not function.  On this EVM,  65ma is used for 3v3 board.

-        toolbox 2_5_1

• IWr1443 ES2 EVM, SOP0, reset button pushed - .136A
• IWR1443 ES2 EVM, SOP0, SOP2, flashing - .186A
• IWR1443 ES2 EVM, SOP0, with High Accuracy lab, running profile_2db.txt - .276

Regards

Joe Quintal

Hello,
There are several large inrush sources:
a) initial turn on of EVM, the CL filter, having another inductor before the capacitor would limit inrush.
- when we have done EVM turn on tests we have seen a 1.3 amp 5v peak
b) as soon as the 5v input is > PMIC turnon voltage, there is a second inrush < 1 amp
c) the mmwave sensor has high peaking currents in the 1v3_RF1, 1v3_RF2, and 1v8 supplies. (.9amp @ 1.8v, 1.9amp @ 1.3v)

Initially we used a regulated 2A 5v supply for IWr1443, and a regulated 2.5A supply for IWR1642. I think 2.5A was used as a single recommendation.

The mmwave sensor has different power profiles depending on the
number of Rx and Tx RF ports that are active, the RF_On time within the frame, and if the DSP is used.

The power efficiency of the DC supply has an impact as well.
1) the standard EVM power efficiency < 50%
2) following the swra577, replacing the LP87524B->J, removing the RF LDOs, adding 2nd stage LC filters , power efficiency ~60%
3) after adding (b), using I2C to reprogram the BUC2 1.3v, BUC2 (1.3v) Auto-PFM/PWM, BUC3 (1.8v) Auto-PFM/PWM, need to check
the Radar operation for different power noise effects, power efficiency ~70%.

Regards,
Joe Quintal