Rainbow Electronics MAX6948B - Manual (Page 10)

High-Efficiency PWM LED Driver with Boost
Converter and Five Constant-Current GPIO Ports
10
MAX6948B
Register Description
The MAX6948B contains 25 internal registers (Table 1).
Registers 0x00 to 0x15 control ports P0–P4 and remain
compatible with the MAX6946/MAX6947 port expanders.
Register 0x20 and 0x21 set the PWM duty cycle for the
integrated boost converter. Register 0x22 conveys the
boost-converter status.
Table 1. Register Address Map and Autoincrement Address
ADDRESS
CODE (hex)
AUTO-INCREMENT
ADDRESS (hex)
READ/
WRITE
REGISTER
FUNCTION
DESCRIPTION
0x00 0x01 R/W P0 Port P0 I/O control and PWM settings
0x01 0x02 R/W P1 Port P1 I/O control and PWM settings
0x02 0x03 R/W P2 Port P2 I/O control and PWM settings
0x03 0x04 R/W P3 Port P3 I/O control and PWM settings
0x04 0x10 R/W P4 Port P4 I/O control and PWM settings
0x05 — — Reserved —
0x06 — — Reserved —
0x07 — — Reserved —
0x08 — — Reserved —
0x09 — — Reserved —
0x0A 0x10 R/W
Group control
(P0–P4)
Write: Simultaneously sets I/O and PWM settings for
ports P0–P4
Read: Reads contents of address 0x00
0x0B 0x10 R/W
Group control
(P0, P1)
Write: Simultaneously sets I/O and PWM settings for
ports P0, P1
Read: Reads contents of address 0x00
0x0C 0x10 R/W
Group control
(P2, P3, P4)
Write: Simultaneously sets I/O and PWM settings for
ports P2, P3, P4
Read: Reads contents of address 0x00
0x0D 0x10 — Reserved —
0x0E 0x0E Read only Port input Reads GPIO input values
0x0F — — Reserved —
0x10 0x11 R/W Configuration
Half-/full-boost current, reset options, PWM stagger,
start/stop status, reset run, shutdown setting
0x11 0x12 R/W Ramp-down Port ramp-down and hold-off settings
0x12 0x13 R/W Ramp-up Port ramp-up setting
0x13 0x14 R/W Output current Port half-/full-current settings
0x14 — — Reserved —
0x15 0x10 R/W Global current Port maximum current setting
0x20 0x21 R/W
Boost PWM
(MSB)
Boost circuit LED PWM setting (MSB)
0x21 — R/W Boost PWM (LSB) Boost circuit LED PWM setting (LSB)
0x22 — R/W Boost status Boost circuit status and standby setting