Rainbow Electronics MAX1821 - Manual (Page 2)

MAX1820/MAX1821
WCDMA Cellular Phone 600mA
Buck Regulators
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
BATT, OUT (FB), SHDN, SYNC, SKIP,
REF to GND .......................................................-0.3V to +6.0V
PGND to GND .......................................................-0.3V to +0.3V
LX, COMP to GND...................................-0.3V to (V
BATT + 0.3V)
Output Short-Circuit Duration ............................................Infinite
Continuous Power Dissipation (T
A = +70°C)
3 ✕ 4 UCSP (derate 10.4mW/°C above +70°C)............832mW
10-Pin µMAX (derate 5.6mW/°C above +70°C) ...........444mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Ranges
3 ✕ 4 UCSP ....................................................-40°C to +150°C
10-Pin µMAX ..................................................-65°C to +150°C
Solder Profile (UCSP) ......................................................(Note 1)
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Input BATT Voltage V IN 2.6 5.5 V
Undervoltage Lockout
Threshold
V UVLO V BATT rising, 1% hysteresis 2.20 2.35 2.55 V
SKIP = GND (MAX1820Z/MAX1821) 180 300
SKIP = BATT, no switching 450 2000
SKIP = GND (MAX1820Y, MAX1820X, and
MAX1821X)
240 360
Quiescent Current I Q
SKIP = BATT, 1MHz switching 3300
µA
SKIP = GND 530 1000
Quiescent Current in Dropout
SKIP = BATT, no switching 550 1000
µA
Shutdown Supply Current I SHDN
SHDN = GND 0.1 6 µA
ERROR AMPLIFIER
V REF = 1.932 ±0.005V, load = 0 to 600mA,
SKIP = BATT or GND
3.33 3.4 3.47
OUT Voltage Accuracy
(MAX1820)
V OUT
V REF = 0.227 ±0.005V, load = 0 to 30mA,
SKIP = BATT, V
BATT
≤ 4.2V
0.35 0.40 0.45
V
OUT Input Resistance
(MAX1820)
R OUT 250 400 k Ω
REF Input Current (MAX1820) I REF 0.1 1 µA
FB Voltage Accuracy
(MAX1821)
V FB FB = COMP 1.225 1.25 1.275 V
FB Input Current (MAX1821) I FB V FB = 1.4V 0.01 50 nA
Transconductance g m 30 50 85 µS
COMP Clamp Low Voltage 0.2 0.45 1.0 V
COMP Clamp High Voltage 2.04 2.15 2.28 V
ELECTRICAL CHARACTERISTICS
(V BATT = 3.6V, SHDN = BATT, SKIP = SYNC = GND, V REF = 1.25V (MAX1820 only), T A = 0°C to +85°C, unless otherwise noted.
Typical values are at T A = +25°C.) (Note 2)
Note 1: For UCSP solder profile information, visit www.maxim-ic.com/1st_pages/UCSP.htm.