LED behaves differently with Nano vs Uno

Other Hardware LEDs and Multiplexing
1

I wasn't sure where to put this: please let me know if it belongs in some other area.

I developed a simple flickering candle LED application using a Uno and then purchased a Nano for the final product, because the Nano is so much smaller. I was using A11 on the Uno, but switched to A5 for the Nano. Problem is that analogWrite() seems to be able to display a variety of light levels on the Uno, but with the Nano, the LED is either on or off. The code is below. I inserted the "for" loop as a diagnostic so that I could see the LED go from dim to bright, but it is just flashing (on or off) on the Nano. The LED is the same on both the Uno and the Nano.

Any thoughts?

int LED = A5;

void setup() {
pinMode(LED, OUTPUT);
}

void loop() {
// added for diagnosis
for (int i = 0; i <= 255; i = i + 10) {
analogWrite(LED, i);
delay(100);
}

analogWrite(LED, 125 + random(125));
delay(random(80));
}

2

Never mind. I found a reference that compared pins between the Uno and the Nano. I needed to use Digital 5 rather than Analog 5. I was confused because Analog 11 works properly on the Uno.

3

Still confused. There is a D11 on an Uno, but not an A11.
And analogWrite only works on PWM pins, not on analogue pins.
Leo..