Rainbow Electronics MAX6948B - Manual (Page 11)

High-Efficiency PWM LED Driver with Boost
Converter and Five Constant-Current GPIO Ports
11
MAX6948B
Configuration Register Format (0x10)
Use the configuration register to select PWM phasing
between outputs, monitor fade status, enable hardware
startup from shutdown, and select shutdown or run mode
(Table 2).
Initial Power-Up
On power-up, all control registers are set to power-
up values and the MAX6948B is in shutdown mode
(Table 3).
Table 2. Configuration Register Format (0x10)
Table 3. Power-On Reset (POR) Values
REGISTER BIT DESCRIPTION VALUE FUNCTION DEFAULT VALUE
D7 Half-/full-boost current
1 Half-boost current set by R FB
1
0 Full-boost current set by R FB
D6 Reset/POR option
0 RST does not change register data
0
1 RST resets registers to POR values
D5 PWM stagger
0 PWM outputs are in phase
0
1 PWM outputs are staggered
D4 Hold-off status
0 Device is not in hold-off
Read only
1 Device is in hold-off
D3 Ramp-down (fade-off) status
0 Device is not in fade-off
Read only
1 Device is in fade-off
D2 Ramp-up status
0 Device is not in ramp-up
Read only
1 Device is in ramp-up
D1 Reset-run enable
0 Reset run disabled
0
1 Reset run enabled
D0 Run
0 Shutdown mode
0
1 Run mode
ADDRESS
CODE (hex)
READ/
WRITE
POWER-UP
VALUE (hex)
REGISTER FUNCTION POR DESCRIPTION
0x00 R/W 0xFF P0 Port P0 high impedance
0x01 R/W 0xFF P1 Port P1 high impedance
0x02 R/W 0xFF P2 Port P2 high impedance
0x03 R/W 0xFF P3 Port P3 high impedance
0x04 R/W 0xFF P4 Port P4 high impedance
0x10 R/W 0x00 Configuration Shutdown mode (reset run disabled)
0x11 R/W 0x00 Ramp-down Port ramp-down and hold-off disabled
0x12 R/W 0x00 Ramp-up Port ramp-up disabled
0x13 R/W 0x03 Output current P0, P1 at full current; P2, P3, P4 at half current
0x15 R/W 0x07 Global current Maximum output current
0x20 R/W 0x00 Boost PWM (MSB) Zero PWM duty cycle
0x21 R/W 0x00 Boost PWM (LSB) Zero PWM duty cycle
0x22 R/W 0x01 Boost status Boost circuit in standby mode