LP8720TLE NSC [National Semiconductor], LP8720TLE Datasheet - Page 9

• Manufacturer Part Number: LP8720TLE
• Description: One Step-Down DC/DC and Five Linear Regulators with I2C Compatible Interface
• Manufacturer: NSC [National Semiconductor]

EXT_DVS_CONTROL
EXT_SLEEP_CONTROL
SHORT_TIMESTEP
LDO1_V[4:0]
LDO2_V[4:0]
LDO3_V[4:0]
LDO5_V[4:0]
LDO4_V[4:0]
BUCK_V1[4:0] BUCK_V2[4:0]
LDO1_T[2:0]
LDO2_T[2:0]
LDO3_T[2:0]
LDO4_T[2:0]
LDO5_T[2:0]
BUCK_T[2:0]
FORCE_PWM
Register 0x00
Registers 0x01 – 0x07
1 – DVS-pin control:
0 – Serial interface control:
1 – DVS-pin control:
0 – Serial interface control:
1 – time step t
0 – time step t
By request time step 100 µs/200 µs is available.
00000 – 1.20V
00001 – 1.25V
00010 – 1.30V
00011 – 1.35V
00100 – 1.40V
00101 – 1.45V
00110 – 1.50V
00111 – 1.55V
00000 – 0.80V
00001 – 0.85V
00010 – 0.90V
00011 – 1.00V
00100 – 1.10V
00101 – 1.20V
00110 – 1.25V
00111 – 1.30V
0000
External resistor divider
00001 – 0.80V
00010 – 0.85V
00011 – 0.90V
00100 – 0.95V
00101 – 1.00V
00110 – 1.05V
00111 – 1.10V
BUCK_V1[4:0] should be higher (or equal) than BUCK_V2[4:0].
000 – start up delay 0
001 – start up delay = 1 * time step t
010 – start up delay = 2 * time step t
011 – start up delay = 3 * time step t
For proper startup operation “111 NO start up” should have corresponding bit in ENABLE_BITS
register 0x08 set to 0 (disable).
1 – Buck is forced to work in PWM mode
0 – Buck works in automatic PFM/PWM selection mode.
DVS=HI then BUCK_V1[4:0]
DVS=LO then BUCK_V2[4:0]
DVS_V2/V1=1 then BUCK_V1[4:0]
DVS_V2/V1=0 then BUCK_V2[4:0]
DVS=HI then normal
DVS=LO then SLEEP
SLEEP_MODE=0 then normal
SLEEP_MODE=1 then SLEEP
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=25 µs
=50 µs
01000 – 1.60V
01001 – 1.65V
01010 – 1.70V
01011 – 1.75V
01100 – 1.80V
01101 – 1.85V
01110 – 1.90V
01111 – 2.00V
01000 – 1.35V
01001 – 1.40V
01010 – 1.45V
01011 – 1.50V
01100 – 1.55V
01101 – 1.60V
01110 – 1.65V
01111 – 1.70V
01000 – 1.15V
01001 – 1.20V
01010 – 1.25V
01011 – 1.30V
01100 – 1.35V
01101 – 1.40V
01110 – 1.45V
01111 – 1.50V
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10000 – 2.10V
10001 – 2.20V
10010 – 2.30V
10011 – 2.40V
10100 – 2.50V
10101 – 2.60V
10110 – 2.65V
10111 – 2.70V
10000 – 1.75V
10001 – 1.80V
10010 – 1.85V
10011 – 1.90V
10100 – 2.00V
10101 – 2.10V
10110 – 2.20V
10111 – 2.30V
10000 – 1.55V
10001 – 1.60V
10010 – 1.65V
10011 – 1.70V
10100 – 1.75V
10101 – 1.80V
10110 – 1.85V
10111 – 1.90V
100 – start up delay = 4 * time step t
101 – start up delay = 5 * time step t
110 – start up delay = 6 * time step t
111 – NO startup
11000 – 2.75V
11001 – 2.80V
11010 – 2.85V
11011 – 2.90V
11100 – 2.95V
11101 – 3.00V
11110 – 3.10V
11111 – 3.30V
11000 – 2.40V
11001 – 2.50V
11010 – 2.60V
11011 – 2.65V
11100 – 2.70V
11101 – 2.75V
11110 – 2.80V
11111 – 2.85V
11000 – 1.95V
11001 – 2.00V
11010 – 2.05V
11011 – 2.10V
11100 – 2.15V
11101 – 2.20V
11110 – 2.25V
11111 – 2.30V
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