TS-8820 Dual H Bridge

The TS-8820 is able to support dual H Bridge drivers via an ST L6205 DMOS Dual Full Bridge driver. Through the TS-8820, each H Bridge can be independently controlled in all states of operation -- forward, reverse, coast (free-wheel), and brake -- with either a PWM signal or a constant drive voltage. PWM can be used to ramp up or down an attached load as well as to maintain it at a constant specified rate.

The H Bridge power source is from the main power supply. Please ensure that the input is able to supply enough power to the load in order to not disrupt the rest of the system operations.

The two H Bridges are exposed on the P6 terminal block, pins 1 through 4. The first output pair is marked "1A" and "1B," with the second pair being "2A" and "2B."

Below are some examples of controlling the H Bridges from the command line:

# Set H Bridge 1 to forward direction at 75% duty cycle
ts8820ctl --hbridge1 --fwd 750

# Set H Bridge 2 to reverse direction at 100% duty cycle
ts8820ctl --hbridge2 --rev 1000

# Brake H Bridge 1 (turns off PWM and grounds both sides of the H Bridge)
ts8820ctl --hbridge1 --brake

# Let H Bridge 2 coast to a stop, aka free-wheel
ts8820ctl --hbridge2 --coast

Additionally, the "--prescaler" flag can be passed to adjust the driving frequency:

# 381 Hz @ 50% duty cycle in the forward direction
ts8820ctl --hbridge1 --fwd 500 --prescaler 5

The prescaler value is 0-7, the output frequency can be calculated with (12207/(2^prescaler)). A lookup table has been provided below.

H Bridge PWM Freq.

Prescaler	Freq.
0	12207 Hz
1	6103 Hz
2	3052 Hz
3	1526 Hz
4	763 Hz
5	381 Hz
6	191 Hz
7	95 Hz