Rainbow Electronics MAX847 - Manual (Page 3)

MAX847
1-Cell, Step-Up
Two-Way Pager System IC
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ELECTRICAL CHARACTERISTICS (continued)
(OUT = 3.0V, BATT = 1.2V, NICD = 3.6V, T A = -40°C to +85°C, unless otherwise noted. Typical values are at T A = +25°C.) (Note 1)
% -3.5 3.5
OUT Error, Coast Mode
(Note 11)
I OUT = 1mA to 80mA, Run Mode mV 25 OUT Load Regulation
Coast Mode, OUT = 1.8V to 4.9V
Circuit of Figure 2, OUT = 3.0V, BATT = 1.1V
Circuit of Figure 2, OUT = 3.0V, BATT = 1.0V
CONDITIONS
BATT = 0.8V to 1.5V mV 25 OUT Line Regulation
LX1
Ω
0.45 0.9
LX1 On-Resistance
ns 100 CS Pulse Width High, t
CSW
ns 70 SCL to SDO Output Valid, t DO
ns 50
SCL Pulse Width High or Low,
t
CH , t CL
mA 80 115
Output Current, Run Mode
(Note 10)
mA 15 40
Output Current, Coast Mode
(Note 10)
UNITS MIN TYP MAX PARAMETER
NMOS
PMOS 0.65 1.3
T A = +25°C, FILT connected to REF kHz 210 270 325 Frequency, Free-Run
f SYNC = 38.4kHz kHz 268.8 Frequency, Locked
f SYNC = 38.4kHz, FILT network = 1nF  (22nF + 10k Ω ) kHz ±15 Jitter (Note 14)
f SYNC = 38.4kHz, FILT network = 1nF  (22nF + 10k Ω ) ms 1 25 Capture Time (Note 14)
0.2V < (OUT - NICD) < 2V, 15mA_CHG = 1 mA 7 25 Current High
0.2V < (OUT - NICD) < 2V, 1mA_CHG = 1 mA 0.45 1.5 Current Low
OUT = 2.8V, I OUT = 20mA, NICD = 3.3V % -3.5 3.5 OUT Error, Backup Regulator
Backup Mode, NICD = 3.3V
Ω
5 10
Backup-Regulator
On-Resistance (Note 15)
ns 70 CS to SDO Disable, t
TR
% -3.5 3.5
OUT Error, Run Mode
(Note 12)
Run Mode, OUT = 1.8V to 4.9V
mV 30 100 170
OUT DAC Step Size
(Note 13) Coast or Run Mode,
OUT = 1.8V to 4.9V
ns 50
ns 50 CS to SCL Hold Time, t
CSH
CS to SCL Setup Time, t
CSS
ns 70 CS to SDO Output Valid, t
DV
OUT = 3.0V % 76 83 Maximum LX1 Duty Cycle
I OUT = 80mA, C OUT = 47µF with ESR < 0.25
Ω
mVp-p 70 OUT Voltage Ripple
During the inductor charge cycle mA 480 600 720 LX1 Switch Current Limit
DC-DC CONVERTER
PHASE-LOCKED LOOP (PLL)
NICD CHARGER